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NJU6631A
PRELIMINARY 16-CHARACTER 1-LINE DOT MATRIX LCD CONTROLLER DRIVER
s GENERAL DESCRIPTION
The NJU6631A is a 1 Chip Dot Matrix LCD controller driver for up to 16-character 1-line or 8-character 2-line display. It contains microprocessor interface circuits, instruction decoder controller, character generator ROM/RAM and common and segment drivers. The bleeder resistance generates for LCD Bias voltage internally. The CR oscillator incorporates C and R, therefore no external components for oscillation are required. The microprocessor interface circuits which operate 2MHz frequency, can be connected directly to 4bit/8bit microprocessor. The character generator consists of 9,600 bits ROM and 32 x 5 bits RAM. The standard version ROM is coded with 192 characters including capital and small letter fonts. The 16-common and 40-segment drives up to 16character 1-line LCD panels which divided two common electrode blocks. The rectangle outlook is very applicable to COG or Slim TCP.
s PACKAGE OUTLINE
NJU6631ACH
s FEATURES
q q q q q q q q q q q q q q q q q q 16-character 1-line Dot Matrix LCD Controller Driver 4/8 Bit Microprocessor Direct Interface Display Data RAM - 16 x 8 bits : Maximum 16-character 1-line Display Character Generator ROM - 9,600 bits : 240 Characters for 5 x 8 Dots Character Generator RAM - 32 x 5 bits : 4 Patterns(5 x 8 Dots) Microprocessor can access to Display Data RAM and Character Generator RAM High Voltage LCD Driver : 16-common / 40-segment Duty Ratio : 1/16 Duty Number of Maximum Display Characters : 16-character Useful Instruction Set Clear Display, Return Home, Display ON/OFF Cont, Cursor ON/OFF Cont, Display Blink, Cursor Shift, Character Shift, Common and Segment driver Location order Select Function(Pin configuration mode A / mode B) Power On Initialize / Hardware Reset Function Bleeder Resistance On-chip Oscillation Circuit On-chip Low Power Consumption Operating Voltage --- +5V Package Outline --- Bumped Chip C-MOS Technology 31.Mar,2000 Ver.1
NJU6631A
s PAD LOCATION
31 74 Y X
18 1
Chip Size : 3.58mm x 1.68mm Chip Center : X=0um, Y=0um Bump Material : Au
Bump Size Bump Height
: 90um x 55um : 17.5um TYP.
s BLOCK DIAGRAM
RESET Instruction Reg.(IR)
Power On Reset
8
Instruction 7 Address Decoder(ID) Counter(AC) 7 Display Data RAM (DD RAM) 16x8bits 8 8 5 8 Character Generator ROM (CG ROM) 9,600bits 5 Parallel to Serial Converter 7
Timing Gen.
16bit Shift Reg.
Cursor Blink Cont.
7 8 8
16
Common Driver Segment Driver
OSC1 OSC2
CR OSC
I/O Buffer
8
Data Reg. (DR)
RS R/W E DB4DB7 DB0DB3 VSS
VDD R1
16 COM 1 COM16
Latch
4 4
5
Busy Flag
Character Generator RAM (CG RAM) 32x5bits 5
40
40
V1
40bit Shift Reg.
LCD Driver
R1 V2 R1 V3 R1 V4 R1 V5
40bit
SEG1 SEG40
NJU6631A
s PAD COORDINATES
PAD Name Pin Configuration Mode A Mode B Dummy1 Dummy1 VDD VDD VDD VDD VDD VDD V5 V5 V5 V5 V5 V5 V3 V3 V2 V2 RESET RESET RS RS R/W R/W E E DB0 DB0 DB1 DB1 DB2 DB2 Dummy2 Dummy2 DB3 DB3 DB4 DB4 DB5 DB5 DB6 DB6 DB7 DB7 COM1 COM9 COM2 COM10 COM3 COM11 COM4 COM12 COM5 COM13 COM6 COM14 COM7 COM15 COM8 COM16 Dummy3 Dummy3 Dummy4 Dummy4 SEG1 SEG40 SEG2 SEG39 SEG3 SEG38 SEG4 SEG37 SEG5 SEG36 SEG6 SEG35 SEG7 SEG34 SEG8 SEG33 SEG9 SEG32 SEG10 SEG31 SEG11 SEG30 Center X=(um) -1501 -1426 -1353 -1281 -1138 -1066 -993 -844 -614 -98 132 361 591 824 1091 1328 1406 1630 1630 1630 1630 1630 1630 1630 1630 1630 1630 1630 1630 1630 1459 1383 1313 1243 1173 1103 1033 963 893 823 753 683 613 Y=(um) -680 -680 -680 -680 -680 -680 -680 -680 -680 -680 -680 -680 -680 -680 -680 -680 -680 -486 -416 -322 -253 -160 -13 57 127 197 267 337 407 477 690 690 690 690 690 690 690 690 690 690 690 690 690 Chip Size 3.58x1.68mm(Chip Center X=0um,Y=0um) PAD Name Center PAD Pin Configuration No. X=(um) Y=(um) Mode A Mode B 44 SEG12 SEG29 543 690 45 SEG13 SEG28 473 690 46 SEG14 SEG27 403 690 47 SEG15 SEG26 333 690 48 SEG16 SEG25 263 690 49 SEG17 SEG24 193 690 50 SEG18 SEG23 123 690 51 SEG19 SEG22 53 690 52 SEG20 SEG21 -17 690 53 SEG21 SEG20 -87 690 54 SEG22 SEG19 -157 690 55 SEG23 SEG18 -227 690 56 SEG24 SEG17 -297 690 57 SEG25 SEG16 -367 690 58 SEG26 SEG15 -437 690 59 SEG27 SEG14 -507 690 60 SEG28 SEG13 -577 690 61 SEG29 SEG12 -647 690 62 SEG30 SEG11 -717 690 63 SEG31 SEG10 -787 690 64 SEG32 SEG9 -857 690 65 SEG33 SEG8 -927 690 66 SEG34 SEG7 -997 690 67 SEG35 SEG6 -1067 690 68 SEG36 SEG5 -1137 690 69 SEG37 SEG4 -1207 690 70 SEG38 SEG3 -1277 690 71 SEG39 SEG2 -1347 690 72 SEG40 SEG1 -1417 690 73 Dummy5 Dummy5 -1501 690 74 COM16 COM8 -1630 402 75 COM15 COM7 -1630 332 76 COM14 COM6 -1630 262 77 COM13 COM5 -1630 192 78 COM12 COM4 -1630 122 79 COM11 COM3 -1630 52 80 COM10 COM2 -1630 -18 81 COM9 COM1 -1630 -88 82 OSC1 OSC1 -1630 -230 83 OSC2 OSC2 -1630 -300 84 VSS VSS -1630 -370 85 VSS VSS -1630 -443 86 VSS VSS -1630 -515
PAD No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43
Note) Dummy1 Dummy5 are Dummy Pad.
NJU6631A
s TERMINAL DESCRIPTION
PAD No. Pin Configuration Mode A Mode B 2,3,4 2,3,4 84,85,86 84,85,86 9,8, 9,8, 7,6,5 7,6,5 82 83 82 83 SYMBOL VDD VSS V2,V3, V5 OSC1 OSC2 Power Source (+5V) Power Source ( 0V) LCD Driving Power Source Oscillation Frequency Adjust Terminals. Normally Open. (Oscillation C and R are incorporated, OSC Freq.=270kHz) For external clock operation, the clock should be input on OSC1. Register selection signal input "0" : Instruction Register (Writing) Busy Flag (Reading) "1" : Data Register (Writing/Reading) Read/Write selection signal input "0" : Write, "1" : Read Read/Write activation signal input 3-state Data Bus (Upper) to transfer the data between MPU and NJU6631A DB7 is also used for the Busy flag reading. 3-state Data Bus (Lower) to transfer the data between MPU and NJU6631A These bus are not used in the 4-bit operation. LCD Common driving signal Terminals Common driver Location order Select as Shown in Table 4. Pin configuration mode A : M0=0 / mode B : M0=1. LCD Segment driving signal Terminals Segment driver Location order Select as Shown in Table 4. Pin configuration mode A : M0=0 / mode B : M0=1. Reset Terminal. When the "L" level input over than 1.2ms to this terminal the system will be reset. (fOSC=270kHz) FUNCTION
11
11
RS
12 13 2219
12 13 2219
R/W E DB7DB4
1814
1814
DB3DB0 COM1COM8 COM9COM16 SEG1SEG40
2330 8174
8174 2330
3372
7233
10
10
RESET
NJU6631A
s FUNCTIONAL DESCRIPTION
(1) Description for each blocks (1-1) Register The NJU6631A incorporates two 8-bit registers, an Instruction Register (IR) and a Data Register (DR). The Register (IR) stores instruction codes such as "Clear Display" and "Return Home", and address data for Display Data RAM (DD RAM) and Character Generator RAM (CG RAM). The MPU can write the instruction code and address data to the Register (IR), but it cannot read out from the Register (IR). The Register (DR) is a temporary stored register, the data stored in the Register (DR) is written into the DD RAM or CG RAM and read out from the DD RAM or CG RAM. The data in the Register (DR) written by the MPU is transferred automatically to the DD RAM or CG RAM by internal operation. When the address data for the DD RAM or CG RAM is written into the Register (IR), the addressed data in the DD RAM or CG RAM is transferred to the Register (DR). By the MPU read out the data in the Register (DR), the data transmitting process is performed completely. After reading the data in the Register (DR) by the MPU, the next address data in the DD RAM or CG RAM is transferred automatically to the Register (DR) to provide for the next MPU reading. These two registers are selected by the selection signal RS as shown below : Table 1. shows register operation controlled by RS and R/W signals. Table 1. Register Operation RS 0 0 1 1 R/W 0 1 0 1 Selected Register IR DR Operation Write Read busy flag (DB7) and address counter (DB0DB6) Write (DR to DD RAM or CG RAM) Read (DD RAM or CG RAM to DR)
(1-2) Busy Flag (BF) When the internal circuits are in the operation mode, the busy flag is "1", and any instruction reading is inhibited. The busy flag (BF) is output at DB7 when RS="0" and R/W="1" as shown in table 1. The next instruction should be written after busy flag (BF) goes to "0". (1-3) Address Counter (AC) The address Counter (AC) addressing the DD RAM and CG RAM. When the address setting instruction is written into the Register (IR), the address information is transferred from Register (IR) to counter (AC). The selection of either the DD RAM or CG RAM is also determined by this instruction. After writing (or reading) the display data to (or from) the DD RAM or CG RAM, the Counter (AC) increments (or decrements) automatically. The address data in the Counter (AC) is output from DB6DB0 when RS="0" and R/W="1" as shown in Table 1. (1-4) Display Data RAM (DD RAM) The display data RAM (DD RAM) consists of 16 x 8 bits, stores up to 16-character display data represented in 8-bit code. The DD RAM address data set in the address Counter (AC) is represented in Hexadecimal. Higher order bit AC
AC6 AC5 AC4 AC3
Lower order bit
AC2 AC1 AC0
(Example) DD RAM address "08" 0 0 0 1 0 0 8
0
0
Hexadecimal
Hexadecimal
NJU6631A
(1-4-1) 16-character 1-line Display The NJU6631A has two kinds of addressing mode called "Addressing mode 1" and "Addressing mode 2" which is determined by the Function Set Instruction (A= 0 and 1). "Addressing mode 1" is using consecutive address of (00)H through (0F)H for front half 8-character and last half 8-character. "Addressing mode 2" is not using consecutive address likes as (00)H through (07)H and (40)H through (47)H for front half 8-character and last half 8-character respectively. 16-character 1-line and 8 character 2-line are also determined by the Function Set Instruction (M1= 0 and 1). -The relation between DD RAM address and display position on the LCD is shown below. 1 00 2 01 3 02 4 03 5 04 6 05 7 06 8 07 9 08 10 09 11 0A 12 0B 13 0C 14 0D 15 0E 16 0F Display position DD RAM address (Hexadecimal)
COM1COM8
COM9COM16
When the display shift is performed, the DD RAM address changes as follows: (Left Shift Display) 07 08 09 0A (Right Shift Display) 05 06 07 08
(00)
01
02
03
04
05
06
0B
0C
0D
0E
0F
00
0F
00
01
02
03
04
09
0A
0B
0C
0D
0E
(0F)
-The relation between DD RAM address and display position on the LCD is shown below. 1 00 2 01 3 02 4 03 5 04 6 05 7 06 8 07 9 40 10 41 11 42 12 43 13 44 14 45 15 46 16 47 Display position DD RAM address (Hexadecimal)
COM1COM8
COM9COM16
When the display shift is performed, the DD RAM address changes as follows: (Left Shift Display) 07 40 41 42 (Right Shift Display) 05 06 07 40
(00)
01
02
03
04
05
06
43
44
45
46
47
00
47
00
01
02
03
04
41
42
43
44
45
46
(47)
NJU6631A
(1-4-2) 8-character 2-line -The relation between DD RAM address and display position on the LCD is shown below. 1 2 3 4 5 6 7 8 Display Position DD RAM Address (Hexadecimal)
COM1COM8 1st Line 2nd Line 00 08 01 09 02 0A 03 0B 04 0C 05 0D 06 0E 07 0F
COM9COM16
When the display shift is performed, the DD RAM address changes as follows: (Left Display Shift) 03 04 05 06 0B 0C 0D 0E (Right Display Shift) 01 02 03 04 09 0A 0B 0C
1st Line(00) 2nd Line(08)
01 09
02 0A
07 0F
08 00
1st Line 2nd Line
0F 07
00 08
05 0D
06 0E
(07) (0F)
-The relation between DD RAM address and display position on the LCD is shown below. 1 2 3 4 5 6 7 8 Display Position DD RAM Address (Hexadecimal)
COM1COM8 1st Line 2nd Line 00 40 01 41 02 42 03 43 04 44 05 45 06 46 07 47
COM9COM16
When the display shift is performed, the DD RAM address changes as follows: (Left Display Shift) 03 04 05 06 43 44 45 46 (Right Display Shift) 01 02 03 04 41 42 43 44
1st Line(00) 2nd Line(40)
01 41
02 42
07 47
08 00
1st Line 2nd Line
47 07
00 40
05 45
06 46
(07) (47)
NJU6631A
(1-5) Character Generator ROM (CG ROM) The Character Generator ROM (CG ROM) generates 5 x 8 dots character pattern represented in 8-bit character codes. The storage capacity is up to 240 kinds of 5 x 8 dots character pattern. The correspondence between character code and standard character pattern of NJU6631A is shown in Table 2. User-defined character pattern (Custom Font) are also available by mask option.
NJU6631A
Table 2. CG ROM Character Pattern (ROM version -02)
NJU6631A
(1-6) Character Generator RAM (CG RAM) The character generator RAM (CG RAM) can store any kinds of character pattern in 5 x 7 dots written by the user program to display user's original character pattern. The CG RAM can store 4 kinds of character in 5 x 7 dots mode. To display user's original character pattern stored in the CG RAM, the address data (00)H (03)H should be written to the DD RAM as shown in Table 2. Table 3. shows the correspondence among the character pattern, CG RAM address and Data. Table 3. Correspondence of CG RAM address, DD RAM character code and CG RAM character pattern (5 x 7 dots).
Character Code (DD RAM Data) 76543210 Upper bit Lower bit
CG RAM Address 43210 Upper bit Lower bit 000 001 010 011 00100 101 110 111 000 001 010 011 01100 101 110 111 000 001
0000*
*
00
0000*
*
01
Character Pattern (CG RAM Data) 43210 Upper bit Lower bit 11110 10001 10001 11110 10100 10010 10001 00000 10001 01010 11111 00100 11111 00100 00100 00000
Character Pattern Example (1) Cursor Position
Character Pattern Example (2) Cursor Position
* : Don't Care 0000* * 11 11 1 1 1 1 0 0 1 1 0 1 0 1
Notes : 1.Character code bits 0 to 1 correspond to the CG RAM address 3 and 4 (2 bits : 4 patterns) 2.CG RAM address 0, 1 and 2 designate character pattern Line position. The 8th line is the cursor position and the display is performed by logical OR with cursor. Therefore, in case of the cursor display, the 8th line should be "0". If there is "1" in the 8th line, the bit "1" is always displayed on the cursor position regardless of cursor existence. 3.Character pattern row position correspond to the CG RAM data bits 0 to 4 are shown above. The bits 5 to 7 of the CG RAM do not exist. 4.CG RAM character patterns are selected when character code bits 4 to 7 are all "0" and it is addressed by character code bits 0 to 1. Therefore, the address (00)H, (04)H, (08)H and (0C)H, select the same character pattern as shown in Table 2 and Table 3. 5."1" for CG RAM data corresponds to display On and "0" to display Off.
NJU6631A
(1-7) Timing Generator The timing generator generates a timing signals for the DD RAM, CG RAM, CG ROM and other internal circuits operation. RAM read timing for the display and internal operation timing for MPU access are separately generated, so that they may not interfere with each other. Therefore, when the data write to the DD RAM for example, there will be no undesirable influence, such as flickering, in areas other than the display area. (1-8) LCD Driver LCD driver circuits consist of 16-common driver and 40-segment driver. The 40 bits of character pattern data are shifted in the shift-register and latched when the 40 bits shift performed completely. This latched data controls display driver to output LCD driving waveform. (1-9) Cursor Blinking Control Circuit This circuits controls cursor On/Off and cursor position character blinks. The cursor or blinks appear in the digit residing at the DD RAM address set in the address counter (AC). When the address counter is (04)H, a cursor position is shown as follows :
AC6 AC 0
AC5 0
AC4 0
AC3 0
AC2 1
AC1 0
AC0 0
1 00
2 01
3 02
4 03
5 04
6 05
7 06
8 07
9 08
10 09
11 0A
12 0B
13 0C
14 0D
15 0E
16 0F
Display Position DD RAM Address (Hexadecimal)
Cursor Position NoteThe cursor or blinks appear when the address counter (AC) selects the CG RAM. But the displayed the cursor and blink are meaningless. If the AC storing the CG RAM address data, the cursor and blink are displayed in the meaningless position.
NJU6631A
(2) Power on Initialization by internal circuits (2-1) Initialization by Internal Reset circuits The NJU6631A is automatically initialized by internal power on initialization circuits when the power is turned on. In the internal power on initialization, following instructions are executed. During the Internal power on initialization, the busy flag (BF) is "1" and this status is kept 10 ms after VDD rises to 4.5V. Initialization flow is shown below : Clear Display DL=1 A=0 M0=0 M1=0 D=0 C=0 B=0 : 8-bit long interface data : Addressing mode 1 : Pin configuration mode A : 16-Character 1-Line : Display Off : Cursor Off : Cursor Blink Off NOTE If the condition of power supply rise time described in the Electrical Characteristics is not satisfied, the internal Power On Initialization Circuits will not operate and initialization will not be performed. In this case the initialization by MPU software is required.
Function Set
Display On/Off Control
Entry Mode Set
I/D=1 : Increment by 1 S=0 : No Shift
(2-2) Initialization by Hardware The NJU6631A incorporates RESET terminal to initialize the all system. When the "L" level input over 1.2ms to the RESET terminal, reset sequence is executed. In this time, busy signal output during 10ms after RESET terminal goes to "H". - Reset Circuit System Clock RESET C Q Counter RST S R Q System Reset
RS-F/F Power On Reset - Timing Chart External Reset Signal Counter Output RS-F/F Output Internal Reset Signal Busy 10ms Over than 1.2ms
NJU6631A
(3) Instruction The NJU6631A incorporates two registers, an Instruction Register (IR) and a Data Register (DR). These two registers store control information temporarily to allow interface between NJU6631A and MPU or peripheral ICs operating different cycles. The operation of NJU6631A is determined by this control signal from MPU. The control information includes register selection signals (RS), read/write signals (R/W) and data bus signals (DB0 to DB7). Table 4. shows each instruction and its operating time. Note) The execution time mentioned in Table 4. based on fcp or fosc=270kHz. If the oscillation frequency is changed, the execution time is also changed. Table 4. Table of Instructions Code
RS R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
Instructions Maker Test 0 0 0 0
Description
Exec Time
All "0" code is using for maker testing. Clear Display Display clear and sets DD RAM 0 0 0 0 0 0 0 0 0 1 address 0 in AC. 1.52ms Return Home Sets DD RAM address 0 in AC and returns display being shifted to 000000001 * original position. 37us DD RAM contents remain unchanged. Entry Mode Set Sets cursor move direction and specifies shift of display are 0 0 0 0 0 0 0 1 I/D S performed in data read/write. 37us I/D=1:Increment, I/D=0:Decrement S=1:Accompanies display shift. Display On/Off Sets of display On/Off(D), cursor Control 0 0 0 0 0 0 1 D C B On/Off(C) and blink of cursor 37us position character(B). Cursor or Moves cursor and shifts display Display Shift without changing DD RAM contents S/C=1 : Display shift 0 0 0 0 0 1 S/C R/L * * S/C=0 : Cursor shift 56us R/L=1 : Shift to the right R/L=0 : Shift to the left Function Set Sets interface data length(DL), Display address mode(A). DL=1 : 8 bits, DL=0 : 4 bits A=0 : Addressing mode 1 0 0 0 0 1 DL A * M1 M0 A=1 : Addressing mode 2 37us M1=0: 16-Character 1-Line M1=1: 8-Character 2-Line M0=0: Pin configuration mode A M0=1: Pin configuration mode B Sets CG RAM address. After this Set CG RAM instruction, the data is transferred 37us address 0 0 0 1 * ACG on CG RAM. Sets DD RAM address. After this Set DD RAM instruction, the data is transferred 37us address 0 0 1 ADD on DD RAM. Reads busy flag and AC contents. Read Busy Flag ACDD BF=1 : Internally operating & Address 0 1 BF 0us BF=0 : Can accept instruction * * ACCG Writes data into CG or DD RAMs. Write Data to Write Data(DD RAM) 37us CG or DD RAM 1 0 * * * Write Data(CG RAM) Reads data from CG or DD RAMs. Read Data to Read Data(DD RAM) 56us CG or DD RAM 1 1 * * * Read Data(CG RAM) Explanation of DD RAM : Display data RAM, CG RAM : Character generator RAM Abbreviation A : CG RAM address, A : DD RAM address, Corresponds to cursor address CG DD AC : Address counter used for both of DD and CG RAMs * = Don't Care 0 0 0 0 0 0
NJU6631A
(3-1) Description of each instructions (a) Maker Test Code RS 0 R/W 0 DB7 0 DB6 0 DB5 0 DB4 0 DB3 0 DB2 0 DB1 0 DB0 0
All "0" code in 4-bit length is using for device testing mode (only for maker). Therefore, please avoid all "0" input or no meaning Enable signal input at data "0". (Especially please pay attention the output condition of Enable signal when the power turns on.) All "0" code in 8-bit length is usable for NOP (Not Operating instruction). (b) Clear Display Code RS 0 R/W 0 DB7 0 DB6 0 DB5 0 DB4 0 DB3 0 DB2 0 DB1 0 DB0 1
Clear display instruction is executed when the code "1" is written into DB0. When this instruction is executed, the space code (20)H is written into every DD RAM address, the DD RAM address 0 is set into the address counter and entry mode is set increment. If the cursor or blink are displayed, they are returned to the left end of the LCD. The S of entry mode does not change. Note: The character pattern for character code (20)H must be blank code in the user-defined character pattern(Custom font). (c) Return Home Code RS 0 R/W 0 DB7 0 DB6 0 DB5 0 DB4 0 DB3 0 DB2 0 DB1 1 DB0 * * = Don't Care
Return home instruction is executed when the code "1" is written into DB1. When this instruction is executed, the DD RAM address 0 is set into the address counter. Display is returned its original position if shifted, the cursor or blink are returned to the left end of the LCD, if the cursor or blink are on the display. The DD RAM contents do not change. (d) Entry Mode Set Code RS 0 R/W 0 DB7 0 DB6 0 DB5 0 DB4 0 DB3 0 DB2 1 DB1 I/D DB0 S
Entry mode set instruction which sets the cursor moving direction and display shift On/Off, is executed when the code "1" is written into DB2 and the codes of (I/D) and (S) are written into DB1(I/D) and DB0(S), as shown below. (I/D) sets the address increment or decrement, and the (S) sets the entire display shift in the DD RAM writing. I/D 1 0 S Function Address increment : The address of the DD or CG RAM increment (+1) when the read/write, and the cursor or blink move to the right. Address decrement : The address of the DD or CG RAM decrement (-1) when the read/write, and the cursor or blink move to the left. Function Entire display shift. The shift direction is determined by I/D : shift to the left at I/D=1 and shift to the right at the I/D=0. The shift is operated only for the character, so that it looks as if the cursor stands still and the display moves. The display does not shift when reading from the DD RAM and writing/reading into/from CG RAM. The display does not shifting.
1
0
NJU6631A
(e)Display On/Off Control Code RS 0 R/W 0 DB7 0 DB6 0 DB5 0 DB4 0 DB3 1 DB2 D DB1 C DB0 B
Display On/Off control instruction which controls the display On/Off, the cursor On/Off and the cursor position character blink, is executed when the code "1" is written into DB3 and the codes of (D), (C) and (B) are written into DB2(D), DB1(C) and DB0(B), as shown below. D 1 0 C 1 0 B 1 0 Function Display On. Display Off. In this mode, the display data remains in the DD RAM so that it is retrieved immediately on the display when the D change to 1. Function Cursor On. The cursor is displayed by 5 dots on the 8th line. Cursor Off. Even if the display data write, the I/D etc does not change. Function The cursor position character is blinking. Blinking rate is 303.4ms at or fOSC=270kHz. The blink is displayed alternatively with all on (it means all black) and characters display. The cursor and the blink can be displayed simultaneously. The character does not blink. Cursor Character Font 5 x 7 dots (1) Cursor display example
Alternating display (2) Blink display example
() Cursor / Display Shift Code RS 0 R/W 0 DB7 0 DB6 0 DB5 0 DB4 1 DB3 S/C DB2 R/L DB1 * DB0 * * = Don't Care
The Cursor/Display shift instruction shifts the cursor position or display to the right or left without writing or reading display data. This function is used to correct or search the display. The contents of address counter (AC) does not change by operation of the display shift only. This instruction is executed when the code "1" is written into DB4 and the codes of (S/C) and (R/L) are written into DB3(S/C) and DB2(R/L), as shown below. S/C 0 0 1 1 R/L 0 1 0 1 Function Shifts the cursor position to the left. ((AC) is decremented by 1) Shifts the cursor position to the right. ((AC) is incremented by 1) Shifts the entire display to the left and the cursor follows it. Shifts the entire display to the right and the cursor follows it.
NJU6631A
() Function Set Code RS 0 R/W 0 DB7 0 DB6 0 DB5 1 DB4 DL DB3 A DB2 * DB1 M1 DB0 M0 * = Don't Care
Function set instruction which sets the interface data length, the addressing Mode for the DD RAM, 1-line or 2-line display, and Pin configuration mode, is executed when the code "1" is written into DB5 and the codes of (DL), (A), (M1) and (M0) are written into DB4(DL), DB3(A), DB1(M1) and DB0(M0), as shown below (character font is fixed 5 x 7 dots). (DL) sets the interface data length, (A) sets the DD RAM address mode (00)H through (0F)H or (00)H through (07)H and (40)H through (47)H, (M1) sets the number of display line either the 1-line or 2-line display, and (M0) sets the Pin configuration for Common and Segment drivers as shown in coordinates. NOTE This function set instruction must be performed at the head of the program prior to all other existing instructions (except Busy flag/Address read). This function set instruction can not be executed afterwards unless the interface data length change. DL 1 0 A 0 1 M1 0 1 M0 0 1 Function Set the interface data length to 8 bits (DB7 to DB0). Set the interface data length to 4 bits (DB7 to DB4). The data must be sent or received twice. Function Set the Addressing Mode 1 for the DD RAM. Set the Addressing Mode 2 for the DD RAM. Function Set the 16-Character 1-Line Display. Set the 8-Character 2-Line Display. Function Set the Pin configuration mode A for Common and Segment Driver. Set the Pin configuration mode B for Common and Segment Driver. Refer to coordinates
(h) Set CG RAM Address Code RS 0 R/W 0 DB7 DB6 DB5 DB4 0 1 * A Higher order bit DB3 A DB2 DB1 DB0 A A A Lower order bit * = Don't Care
Set CG RAM address instruction is executed when the code "1" is written into DB6 and the address is written into DB4 to DB0 as shown above. The address data mentioned by binary code "AAAAA" is written into the address counter (AC) together with the CG RAM addressing condition. After this instruction execution, the data writing/reading is performed into/from the CG RAM. (i) Set DD RAM Address Code RS 0 R/W 0 DB7 DB6 DB5 DB4 1 A A A Higher order bit DB3 A DB2 DB1 DB0 A A A Lower order bit
Set DD RAM address instruction is executed when the code "1" is written into DB7 and the address is written into DB6 to DB0 as shown above. The address data mentioned by binary code "AAAAAAA" is written into the address counter (AC) together with the DD RAM addressing condition. After this instruction, the data writing/reading is performed into/from the DD RAM. Note : When the "Addressing mode 1" selection, (00)H through (0F)H are available but (10)H through (7F)H are ignored. When the "Addressing mode 2" selection, (00)H through (07)H and (40)H through (47)H are available but (08)H through (3F)H and (48)H through (7F)H are ignored.
NJU6631A
(j) Read Busy Flag & Address Code RS 0 R/W 1 DB7 DB6 DB5 DB4 BF A A A Higher order bit DB3 A DB2 DB1 DB0 A A A Lower order bit
This instruction reads out the internal status of the NJU6631A. When this instruction is executed, the busy flag (BF) which indicate internal operation is read out from DB7 and the address of CG RAM or DD RAM is read out from DB6 to DB0 (the address for CG RAM or DD RAM is determined by the previous instruction). (BF)=1 indicates that internal operation is in progress. The next instruction is inhibited when (BF)=1. Check the (BF) status before the next write operation. (k) Write Data to CG or DD RAM Code RS 1 R/W 0 DB7 DB6 DB5 DB4 D D D D Higher order bit DB7 DB6 DB5 DB4 * * * D Higher order bit DB3 D DB2 DB1 DB0 D D D Lower order bit DB2 DB1 DB0 D D D Lower order bit (DD RAM)
Code
RS 1
R/W 0
DB3 D
(CG RAM)
Write Data to CG RAM or DD RAM instruction is executed when the code "1" is written into (RS) and code "0" is written into (R/W). By the execution of this instruction, the binary 5-bit data "DDDDD" are written into the CG RAM, and the binary 8-bit data "DDDDDDDD" are written into the DD RAM. The selection of the CG RAM or DD RAM is determined by the previous instruction. After this instruction execution, the address increment (+1) or decrement (-1) performed automatically according to the entry mode set. And the display shift is also executed according to the previous entry mode set. (l) Read Data from CG or DD RAM Code RS 1 R/W 1 DB7 DB6 DB5 DB4 D D D D Higher order bit DB7 DB6 DB5 DB4 * * * D Higher order bit DB3 D DB2 DB1 DB0 D D D Lower order bit DB2 DB1 DB0 D D D Lower order bit (DD RAM)
Code
RS 1
R/W 1
DB3 D
(CG RAM)
Read Data from CG RAM or DD RAM instruction is executed when the code "1" is written into (RS) and (R/W). By the execution of this instruction, the binary 5 bit data "DDDDD" are read out from CG RAM, and the binary 8 bit data "DDDDDDDD" are read out from DD RAM. The selection of the CG RAM or DD RAM is determined by the previous instruction. Before executing this instruction, either the CG RAM address set or DD RAM address set must be executed, otherwise the first read out data are invalidated. When this instruction is serially executed, the next address data is normally read from the second read. The address set instruction is not required if the cursor shift instruction is executed just beforehand (only DD RAM reading). The cursor shift instruction has same function as the DD RAM address set, so that after reading the DD RAM, the address increment or decrement is executed automatically according to the entry mode. But display shift does not occur regardless of the entry mode. Note : The address counter(AC) is automatically incremented or decremented by 1 after write instructions to either of the CG RAM or DD RAM. Even if the read instruction is executed after this instruction, the addressed data can not be read out correctly. For a correct data read out, either the address set instruction or cursor shift instruction (only with DD RAM) must be implemented just before this instruction or from the second time read out instruction execution if the read out instruction is executed 2 times consecutively.
NJU6631A
(3-2) Initialization using the internal reset circuits (a) 16-character 1-line in 8-bit operation Addressing Mode 1 (Using internal reset circuits). At the 16-character 1-line display, the Function set, Display On/Off Control and Entry Set Instruction must be executed before the data input, as shown below. Since the display shift operation changes only display position and the DD RAM contents remain unchanged, display data which are entered first can be output when the return home operation is performed. Initialized. No display appears. RS R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 Character 0 0 0 0 1 1 0 * 0 0
Set 8-bit operation, 161-line display, Pin configuration mode A, Addressing Mode 1. the
Power On Function Set Disp. On/Off Control Entry Mode Set Write data to the DD/CG RAM and set the Instruction 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 1 1 1 0
Turns on display and cursor. Entire display is in space mode by the initialization. Example for set address increment and cursor right shift when the data write to the DD or CG RAM.
(b) 8-character 2-line in 4-bit operation Addressing Mode 2 (Using internal reset circuits). In the 4-bit operation, the function set must be performed by the user programming. When the power is turned on, 8-bit operation is selected automatically, therefore the first input is performed under 8-bit operation. In this operation, full instruction can not input because of terminals DB0 to DB3 are no connection. Therefore, same instruction must be rewritten on the RS, R/W and DB7 to DB4, as shown below. Since one operation is completed by the two accesses in the 4-bit operation mode, rewrite is required to set the instruction code in full. 8-character 2-line in 4-bit operation is shown as follows: Initialized. No display appears. RS R/W DB7 DB6 DB5 DB4 Set the 4-bit operation. 0 0 0 0 1 0 This step is executed in 8-bit mode set by the initialization. Set the 4-bit operation / 2-line 8-Character display / Pin configuration mode B / Addressing Mode 2. The 4-bitoperation starts from this step. Turn on display and cursor. Entire display is in space mode by the initialization. Example for set address increment and cursor right shift when the data write to the DD or CG RAM.
Power On Function Set Function Set Disp. On/Off Control Entry Mode Set 0 0 0 0 0 0 0 0 0 1 0 1 0 * 0 1 1 1 0 1 0 1 0 0
0 0
0 0
0 0
0 1
0 1
0 0
Write data to the DD/CG RAM and set the Instruction
NJU6631A
(3-3) Initialization by instruction If the power supply conditions for the correct operation of the internal reset circuits are not met, the NJU6631A must be initialized by the instruction. (a) Initialization by Instruction in 8-bit interface Initialized. No display appears.
Power On Wait more than 15ms after VDD rises to 4.5V Function Set Wait more than 4.1ms Function Set Wait more than 100us Function Set 0 0 0 0 1 1 * * * *
RS R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 Function Set 0 0 0 0 1 1 * * * * (8-bit interface length)
Function Set (8-bit interface length)
RS R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 Function Set (8-bit interface length) 0 0 0 0 1 1 * * * * Busy Flag(BF) can not be checked before this step, but it can be checked after this step. After this step, busy flag(BF) check or longer waiting time than each instruction execution time is required. RS R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 Set the 8-bit operation, 161-Line, Pin 0 0 0 0 1 1 1 * 0 0 Character Configuration mode A, Addressing Mode 2. 0 0 0 0 0 0 1 0 0 0
Function Set Display Off Display Clear Entry Mode Set
0
0
0
0
0
0
0
0
0
1 Example for set address increment and cursor right shift when the data write to the DD or CG RAM.
0
0
0
0
0
0
0
1
1
0
Write data to the DD/CG RAM and set the Instruction
NJU6631A
(b) Initialization by Instruction in 4-bit interface
Power On Wait more than 15ms after VDD rises to 4.5V Function Set Wait more than 4.1ms Function Set Wait more than 100us Function Set 0 0 0 0 1 1 0 0 0 0 1 1
Initialized. No display appears.
RS R/W DB7 DB6 DB5 DB4 Function Set 0 0 0 0 1 1 (8-bit interface length)
Function Set (8-bit interface length)
Function Set (8-bit interface length) Busy Flag (BF) can not be checked before this step, but it can be checked after this step. After this step, busy flag (BF) check or longer waiting time than each instruction execution time is required. Function Set in 8-bit interface length. (Set 4-bit interface length) Set the 4-bit operation, 16-Character 1-Line, Pin Configuration mode A, Addressing Mode 1.
Function Set Display Off Display Clear Entry Mode Set
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 1 0 0 0 0
0 0 * 0 0 0 0 0 1
1 1 0 0 0 0 0 0 1
1 0 0 0 0 0 1 0 0
Example for set address increment and cursor right shift when the data write to the DD or CG RAM.
Write data to the DD/CG RAM and set the Instruction
NJU6631A
(4) LCD Display (4-1) Power Supply for LCD Driving NJU6631A incorporates bleeder resistance to generate the LCD display driving waveform. The bleeder resistance is set 1/5 bias suitable for 1/18 duty ratio and 1.5k per resistance. Furthermore, the bias level can be changed by connecting external resistance between the V2, V3 terminals, if needed. Table 5. LCD Driving Voltage vs Duty Ratio Duty Ratio 1/16 Bias 1/5 Power V2 VDD-2/5VLCD Supply V3 VDD-3/5VLCD VDD-VLCD V5
VDD R1 V1 R1 V2 VLCD V3 R1 V4 R1 V5 V5 NJU6631A internal R1 V3 V2
VDD
Note) Power ON or power OFF is in the following order. Power ON : V5 should be turned on after the VDD turned on or at the same time. Power OFF : V5 should be turned off before the VDD turned off or at the same time.
(4-2) Relation between oscillation frequency and LCD frame frequency. LCD frame frequency example mentioned below is based on 270kHz oscillation. The clock for the LCD Driving is using 270kHz (1 clock=3.7us). 1/16 Duty
40 clock 1 VDD V1 V2 V3 V4 V5 1 frame 1 frame 2 3 4 16 1 2 3 4 16 1 2 3
1 frame=3.7(us)x40x16x4=9,472(ms) Frame frequency=1/9,472(ms)=105.6(Hz)
NJU6631A
s Interface with MPU
NJU6631A can be interfaced with both of 4/8 bit MPU and the two-time 4-bit or one-time 8-bit data transfer is available. (1) When the interface length is 4-bit, the data transfer is performed by 4 lines connected to DB4 to DB7 (DB0 to DB3 are not used). The data transfer with the MPU is completed by the two-time 4-bit data transfer. The data transfer is executed in the sequence of upper 4-bit (the data DB4 to DB7 at 8-bit length) and lower 4-bit (the data DB0 to DB3 at 8-bit length). The busy flag check must be executed after two-time 4-bit data transfer (1 instruction execution). In this case the data of busy flag and address counter are also output twice.
RS R/W E Internal Status DB7 IR7 IR3 Operation Bus AC3 No Bus AC3 D7 D3
Instruction writing
Busy Flag Check
Busy Flag Check
Instruction writing
RS R/W E
DB7 DB6 DB5 DB4
IR7 IR6 IR5 IR4
IR3 IR2 IR1 IR0
BF AC6 AC5 AC4
AC3 AC2 AC1 AC0
DR7 DR6 DR5 DR4
DR3 DR2 DR1 DR0
Writing Instruction into Read out Busy Flag (BF) Read out data Register (DR) instruction Register (IR) and Address counter (AC)
NJU6631A
(2) 8-bit MPU interface
RS R/W E Internal Status DB7 Data Operation Bus Bus No Bus Data
Writing Instruction into instruction Register (IR)
Busy Flag Check
Busy Flag Check
Busy Flag Check
Writing Instruction into instruction Register (IR)
NJU6631A
s ABSOLUTE MAXIMUM RATINGS
PARAMETER Supply Voltage Input Voltage Operating Temperature Storage Temperature VDD VIN Topr Tstg SYMBOL RATINGS -0.3 ~ +7.0 -0.3 ~ VDD + 0.3 -30 ~ +80 -55 ~ +125 (Ta=25C) UNIT V V C C
Note 1) If the LSI are used on condition above the absolute maximum ratings, the LSI may be destroyed. Using the LSI within electrical characteristics is strongly recommended for normal operation. Use beyond the electric characteristics conditions will cause malfunction and poor reliability. Note 2) All voltage values are specified as VSS=0V. Note 3) The relation : VDD>V5V5OUT, VSS=0V must be maintained. Turn on VDD first then turn on V5 must be required. Note 4) Decoupling capacitor should be connected between VDD and VSS due to the stabilized operation for the LSI.
s ELECTRICAL CHARACTERISTICS
Parameter Operating Voltage 1 Input Voltage 2 3 Output Voltage Driver On-resist.(COM) Driver On-resist.(SEG) Input Leakage Current Pull-up Resist. Current Operating Current LCD Driving Voltage Symbol VDD VIH1 VIL1 VIH2 VIL2 VIH3 VIL3 VOH VOL RCOM RSEG ILI -Ip IDD V2 V3 Conditions (VDD=5.0V10%, VSS=0V, Ta= -20~75C) MIN TYP MAX Unit Note 4.5 5.0 5.5 V 125 1.0 3.0 2.0 VDD 0.8 VDD 1.0 VDD 0.2VDD 0.4 20 30 1 250 1.8 3.3 2.3 V 5
All Input/Output Terminals 2.3 except OSC and E Terminals Only OSC Terminal VDD-1.0 Only E Terminal 0.8VDD -IOH=0.205mA 2.4 IOL=1.6mA Id=50uA(All COM term.) Id=50uA(All SEG term.) VIN=0cVDD -1 VDD=5V 50 CR Oscillation VDD=5V, fOSC=270kHz Ta=25C, VDD=5V, V5=0V 2.7 Measurement Terminal is 1.7 SEG. VDD-V5=5V Ta=25C
V k k uA uA mA V
6 9 9 7
8
Bleeder Resistance
RB
6.65
9.5
12.35
k
Oscillation Frequency LCD Driving Voltage
fOSC VLCD
VDD=5V, Ta=25C V5 Terminal, VDD=5V
135 VDD-3
270 -
405 VDD-5
KHz V
10
NJU6631A
Note 5) Input / Output structure except LCD driver are shown below : -Input Terminal Structure E Terminal RS, R/W, RESET Terminals
VDD PMOS
VSS
VDD PMOS
VDD PMOS
NMOS VSS
NMOS VSS
-Input / Output Terminal Structure DB0 ~ DB7
VDD PMOS
VDD PMOS
NMOS VDD PMOS NMOS DATA ENABLE
Note 6) Apply to the Input / Output Terminal. Note 7) Except pull-up resistance current and output driver current. Note 8) Except Input/output current but including the current flow on bleeder resistance. Note 9) RCOM and RSEG are the resistance values between power supply terminals(VDD,V2,V3,V5) and each common terminal (COM1~COM16), and supply voltage (VDD,V2,V3,V5) and each segment terminal (SEG1~SEG40) respectively, and measured when the current Id is flown on every common and segment terminals at a same time. Note 10) Apply to the output voltage from each COM and SEG are less than 0.15V against the LCD Driving constant voltage(VDD, V5) at no load condition. -Bleeder Resistance
VDD R1 V1 R1 V2 R1 V3 R1 V4 R1 V5 V5 NJU6631A internal V3 V2
NJU6631A
s Bus timing characteristics
-Write operation sequence (Write from MPU to NJU6631A) (VDD=5.0V10%, VSS=0V, Ta=-20~75C) SYMBOL MIN. MAX. CONDITION UNIT tCYCE 500 ns PWEH 220 ns 280 ns PWEL tEr, tEf 20 ns fig.1 tAS 40 ns tAH 10 ns tDSW 60 ns tH 10 ns
PARAMETER Enable Cycle Time Enable Pulse "High" level Width "Low" level Enable Rise Time, Fall Time Set up Time RS, R/W-E Address Hold Time Data Set up Time Data Hold Time
Timing Characteristics (Write operation)
VIH1 RS VIL1
VIH1 VIL1
tAS R/W VIL1 PWEH VIH3 VIL3 tEr tDSW VIH1 VIL1 VIH3
tAM VIL1 tAM tEf PWEL VIL3 tH VIH1 VIL1 VIL3
E
DB0DB7
Valid Data
tCYCE
fig. 1 The timing characteristics of the bus write operating sequence. (Write from MPU to NJU6631A)
NJU6631A
-Read operation sequence (Read from NJU6631A to MPU) (VDD=5.0V10%, VSS=0V, Ta=-20~75C) MIN. MAX. CONDITION UNIT 500 ns 220 ns 280 ns 20 ns fig.2 40 ns 10 ns 240 ns 20 ns -DB0~DB7 Load Condition : CL=100pF
PARAMETER Enable Cycle Time Enable Pulse "High" level Width "Low" level Enable Rise Time, Fall Time Set up Time RS, R/W-E Address Hold Time Data Delay Time Data Hold Time
SYMBOL tCYCE PWEH PWEL tEr, tEf tAS tAH tDDR tDHR
Timing Characteristics (Read operation)
VIH1 RS VIL1 tAS R/W VIH1
VIH1 VIL1 tAM VIH1
PWEH VIH3 VIL3 tEr VIH3
tAM tEf PWEL VIL3 VIL3 tDHR VOH1 VOL1 VOH1 VOL1
E
tDDR
DB0DB7
Valid Data
tCYCE
fig. 2 The timing characteristics of the bus read operating sequence. (Read from NJU6631A to MPU)
NJU6631A
-The Input Condition when using the Hardware Reset Circuit PARAMETER SYMBOL CONDITION Reset Input "L" Level Width tRSL fOSC=270kHz MIN. 1.2 TYP. MAX. UNIT ms
Input Timing
tRSL
RESET
fig. 3 The timing characteristics of the Hardware Reset input
*
Power supply condition when using the internal initialization circuit PARAMETER SYMBOL CONDITION MIN Power supply rise time trDD - 0.1 Power supply OFF time tOFF - 1
TYP - -
(Ta=-20 to 75C) MAX UNIT 5 ms - ms
4.5 VDD 0.2 trDD 0.1ms ! trDD ! 10ms 0.2 tOFF tOFF 1ms
3V *tOFF specifies the power OFF time in a short period OFF or cyclical ON/OFF
Note.) Since the internal initialization circuits will not operate normally unless the above conditions are met, in such a case initialize by instruction(Refer to initialization by the instruction).
NJU6631A
s LCD DRIVING WAVEFORM
COM1 COM2 COM3 COM4 COM5 COM6 COM7 COM8 VDD V1 V2 COM9 COM10 COM11 COM12 COM13 COM14 COM15 COM16 COM16 VDD V1 V2 V3 V4 V5 COM2 V3 V4 V5 COM1 VDD V1 V2 V3 V4 V5 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
VDD V1 V2 SEG1 V3 V4 V5
VDD V1 SEG2 V2 V3 V4 V5
NJU6631A
s APPLICATION CIRCUITS
(1) LCD display interface Pin configuration mode A (BOTTOM VIEW)
SEG1
20
40
21
20
1
LCD Panel (16-character 1-line)
21
40
SEG1 COM8
SEG20
SEG21
SEG40 COM16
NJU6631A BOTTOM VIEW
COM1 COM9
Mode A, 16-character 1-line display example (M0=0, M1=0)
LCD Panel (8-character 2-line)
SEG1 COM8
SEG20
SEG21
SEG40 COM16
NJU6631A BOTTOM VIEW
COM1 COM9
Mode A, 8-character 2-line display example (M0=0, M1=1)
NJU6631A
s APPLICATION CIRCUITS
(2) LCD display interface Pin configuration mode B (TOP VIEW)
SEG1
20
40
21
20
1
LCD Panel (16-character 1-line)
21
40
SEG1 COM8
SEG20
SEG21
SEG40 COM16
NJU6631A TOP VIEW
COM1 COM9
Mode B, 16-character 1-line display example (M0=1, M1=0)
LCD Panel (8-character 2-line)
SEG1 COM8
SEG20
SEG21
SEG40 COM16
NJU6631A TOP VIEW
COM1 COM9
Mode B, 8-character 2-line display example (M0=1, M1=1)
MEMO
[CAUTION] The specifications on this databook are only given for information , without any guarantee as regards either mistakes or omissions. The application circuits in this databook are described only to show representative usages of the product and not intended for the guarantee or permission of any right including the industrial rights.

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