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SUMMIT
MICROELECTRONICS, Inc.
SMS45
PRELIMINARY INFORMATION 1 (SEE LAST PAGE)
Quad Programmable Precision Cascade Sequencer and Supervisory Controller with 4k-Bit Nonvolatile Memory
FEATURES
Operational from any of four Voltage Monitoring Inputs Programmable Power-up Cascade Sequencing Programmability allows monitoring any voltage between 0.6V and 5.6V with no external components Programmable 5mV steps in the low range Programmable Watchdog Timer Programmable Reset Pulse Width Programmable Nonvolatile Combinatorial Logic for generation of Reset Fault Status Register 4k-Bit Nonvolatile General Purpose Memory APPLICATIONS Desktop/Notebook/Tablet Computers Multi-voltage Systems Telecom/Network Servers Portable Battery-powered Equipment Set-top Boxes Data-storage Equipment
INTRODUCTION
The SMS45 is a nonvolatile user-programmable voltage supply cascade sequencer and supervisory circuit designed specifically for advanced systems that need to monitor multiple voltages. The SMS45 can monitor four separate voltages without the need of any external voltage divider circuitry unlike other devices that need factorytrimmed threshold voltages and external components to accommodate different supply voltages and tolerances. The SMS45 can also be used to enable DC/DC converters or LDOs to provide a closed loop cascading of the supplies during power -up. The SMS45 watchdog timer has a user programmable time-out period and it can be placed in an idle mode for system initialization or system debug. All of the functions are user accessible through an industry standard I2C 2-wire serial interface. Programming of configuration, control and calibration values by the user is simplified with the SMX3200 interface adapter and Windows GUI software obtainable from Summit Microelectronics.
SIMPLIFIED APPLICATION DRAWING
5V I2C 7 6 9 10 4 DC-DC 3.3V 12 VDD_CAP A2 A1 SDA SCL PUP#1 16 V0 2 V1 3 V2 14 V3 SMS45 PUP#2 1 MR# 15 WLDI GND 8 RESET# 11 PUP#3
0.1F
5
DC-DC
2.5V
Reset#
13
LDO
1.8V
Applications Schematic using the SMS45 Controller to provide closed loop power-up cascade sequencing and supervisory functions.
NOTE: THIS IS AN APPLICATIONS EXAMPLE ONLY. SOME PINS, COMPONENTS AND VALUES ARE NOT SHOWN.
(c)SUMMIT MICROELECTRONICS, Inc., 2004 Characteristics subject to change without notice
* 1717 Fox Dr. * San Jose, CA 95131 * Phone 408-436-9890 * FAX 408-436-9897 * 2079 1.2 05/24/04
www.summitmicro.com
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SMS45
Preliminary Information
INTERNAL BLOCK DIAGRAM
VDD_CAP
50k CONFIGURATION REGISTER 11 RESET#
MR# 1 V0 16
NV DAC + REF - PROGRAMMABLE RESET PULSE GENERATOR
V1 2
NV DAC REF + -
PROGRAMMABLE POWER CASCADING
4 PUP#1 5 PUP#2 13 PUP#3
V2 3
NV DAC REF
+ - PROGRAMMABLE WATCHDOG TIMER
SERIAL BUS CONTROL LOGIC
9 SDA 10 SCL 7 A2 6 A1
V3 14
NV DAC REF + - 50k 15 WLDI SUPPLY ARBITRATION CONFIGURATION REGISTER 4K-BIT NV MEMORY
VDD_CAP
V0 V1 V2 V3
12
8
VDD_CAP
GND
CASCADE SEQUENCING
Time based sequencing has the ability to turn supplies on in a specific order. However, it cannot guarantee that each supply has reached valid voltage levels before the next supply is sequenced on. Cascade sequencing guarantees the supplies are enabled a programmed period of time after the previous voltage has reached its minimum programmed valid level. Figure 1 shows that each succeeding voltage must reach its minimum valid level before the timer is started to time the interval, t, for the next voltage. The duration of each t is programmable for each supply to supply transition. The next supply is not enabled until the timer has elapsed. See also Figure 5.
6V 5V
5V Valid
4V V
3.3V Valid
3.3V 2.5V 2V
2.5V Valid
1.8V
0V
t
t
t
T
2047 Fig01
Figure 1. Cascading Power Supplies
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SMS45
Preliminary Information
PIN CONFIGURATION
PIN NAMES
Pin 1
MR# V1 V2 PUP#1 PUP#2 A1 A2 GND 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 V0 WLDI V3 PUP#3 VDD_CAP RESET# SCL SDA
2047 PCon 2.0
Name MR# V1 V2 PUP#1 PUP#2 A1 A2 GND SD A SC L RESET# PUP#3 V3 WLDI V0
Function Manual reset input Voltage supply and monitor input Voltage supply and monitor input Power up permitted output Power up permitted output Address input Address input Power supply return Serial data I/O Serial data clock Reset out Power up permitted Voltage supply and monitor input Watchdog Timer interrupt Voltage supply and monitor input
2047 Pins Table 2.0
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
VDD_CAP Power supply output
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SMS45
Preliminary Information
ABSOLUTE MAXIMUM RATINGS*
Temperature Under Bias ...................... -55C to 125C Storage Temperature ............................. -65C to 150C Lead Solder Temperature (10s) ........................... 300 C Terminal Voltage with Respect to GND: V0, V1, V2, and V3 ......... -0.3V to 6.0V All Others ....................... -0.3V to 6.0V Junction Temperature........................................150C ESD Rating per JEDEC...................................2000V Latch-Up testing per JEDEC...........................100mA *Note - Stresses beyond the listed Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions outside those listed in the operational sections of this specification is not implied. Exposure to any absolute maximum rating for extended periods may affect device performance and reliability.
RECOMMENDED OPERATING CONDITIONS
Industrial Temperature Range............... -40C to +85C. Commercial Temperature Range..............-5C to +70C. VSUPPLY Supply Voltage............................2.7V to 5.5V VSUPPLY = Device supply voltage provided by the highest VX input. Package Thermal Resistance (JA) 16 Lead SSOP.........................................23oC/W Moisture Classification Level 1 (MSL 1) per J-STD- 020 RELIABILITY CHARACTERISTICS Data Retention.........................................100 Years Endurance........................................100,000 Cycles
DC OPERATING CHARACTERISTICS
(Over Recommended Operating Conditions; Voltages are relative to GND)
Symbol
Parameter
Notes 1V Min. refers to a valid reset output being generated
Min. 1.0
Typ.
Max. 5.5
Unit V
VSUPPLY
Operating supply voltage
Memory read/write operations: at least one of the VX inputs must be at or above VSUPPLY min.
VDD_CAP = 5.5V; V0 trip point 4.7V; V1, V2, V3 = GND; MR# = VCC; all outputs floating
2.7
5.5
V
200
400 3
A mA V V % mV
ICC
Supply current
VPTH Programmable threshold Range range (low range) VPTH Programmable threshold Range range (high range) VPTHACC VHYST VOL VIL VIH Programmable threshold Accuracy VRST hysteresis Low voltage output
Configuration register or memory access Reset threshold voltage range V0 to V3 (5mV increments) Reset threshold voltage range V0 to V3 (15mV increments) VPTH is the programmed threshold setpoint within the VPTH Range See Note 1 below ISINK = 1mA, VVDD_CAP 2.7V ISINK = 200A, VVDD_CAP = 1.0V
0.6 1.8 -1.0 VPTH 30
1.875 5.625 1.0
0.3 0.3 0.6 0.7 x VCC
V V V V
Input threshold
Note 1: Low Range Hysteresis = 4.2 X (Vtrip - 0.5 volts) mV. For Vtrip = 1.0 volts, Hysteresis = 2.1 mV (0.21 %), High Range Hysteresis = 12.6 X (Vtrip -0.5 volts) mV. For Vtrip = 5.0 volts, Hysteresis = 56.7 mV (1.13%).
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SMS45
Preliminary Information
AC OPERATING CHARACTERISTICS
(Over Recommended Operating Conditions; Voltages are relative to GND, also see configuration registers)
Symbol
Parameter WD2 0 0 Programmable Watchdog timer period
Notes WD1 0 1 0 0 1 1 PUP#X-1 0 WD0 X 1 0 1 0 1 PUP#X-0 0 1 0 1
Min.
Typ.
Max.
Unit
OFF 300 600 1200 2400 4800 400 800 1600 3200 6400 500 1000 2000 4000 8000
--
tPWDTO
1 1 1 1
ms
0ms 19 38 75 25 50 100 100 31 63 125
--
tPDLYX
Programmable delay from VPTH to PUP# out
0 1 1
ms
IMR TMR TDMRRST
MR# pullup current MR# input pulse width Delay from MR# low to RESET# low RTO1 0 Programmable reset pulse width RTO0 0 1 0 1 19 38 75 150 Minimum
A ns ns
300 200
25 50 100 200 20
31 63 125 250
ms ms ms ms s
tPRTO
0 1 1
tDRST
V in to RESET# delay
100mV overdrive
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SMS45
Preliminary Information
PIN DESCRIPTIONS
V0, V1, V2, V3 (16, 2, 3, 14) These inputs are used as the voltage monitor inputs and as the voltage supply for the SMS45. Internally they are diode ORed and the input with the highest voltage potential will be the default supply voltage (VDD_CAP). The RESET# output will be valid if any one of the four inputs is above 1V. However, for full device operation at least one of the inputs must be at 2.7V or higher. The sensing threshold for each input is independently programmable in 5mV increments from 0.6V to 1.875V or 15mV increments from 1.8V to 5.625V. Also, the occurrence of an under- or over-voltage condition that is detected as a result of the threshold setting can be used to generate a RESET#. The programmable nature of the threshold voltage eliminates the need for external voltage divider networks. GND Power supply return. MR# (1) The manual reset input always generates a RESET# output whenever it is driven low. The duration of the RESET# output pulse will be initiated when MR# goes low and it will stay low for the duration of MR# low plus the programmed reset time-out period (tPRTO). If MR# is brought low during a power-on cascade of the PUP#s the cascade will be halted for the reset duration, and will then resume from the point at which it was interrupted. MR# must be held low during a configuration register write. This signal is pulled up internally through a 50k resistor. RESET# (11) The reset output is an active low open drain output. It will be driven low whenever the MR# input is low or whenever an enabled under-voltage or over-voltage condition exists. The four voltage monitor inputs are always functioning, but their ability to generate a reset is programmable (configuVPTH-UV V0 -- V3 tPRTO RESET# tDRST
Figure 3. RESET# Timing ration register 4). Refer to Figures 2 and 3 for a detailed illustration of the relationship between MR#, RESET# and the VIN levels. VDD_CAP (12) The VDD_CAP pin connects to the internal supply voltage for the SMS45. A capacitor is placed on this pin to filter supply noise as well as hold up the device in the event of power failure. The voltage on this node is determined by the highest input voltage. Loading of this pin should be minimized to prevent excessive power dissipation in the part. WLDI (15) Watchdog timer input. A high-to-low transition on the WLDI input will clear the watchdog timer, effectively starting a new time-out period. This signal is pulled up internally through a 50k resistor. If WLDI is stuck low and no high-to-low transition is received within the programmed tPWDTO period (programmed watchdog time-out) RESET# will be driven low. Refer to Figure 4 for a detailed illustration. Holding WLDI low will not block the watchdog from timing out and generating a reset. Refer to Figure 4 for a detailed illustration of the relationship between RESET# and WLDI.
t0
tPWDTO t0 t0 t0 t0 tPRTO
MR# tDMRRST RESET# tPRTO
RESET#
tPRTO WLDI
tPWDTO
2047 Fig04 3.0
Figure 2. RESET# Timing with MR#
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Figure 4. Watchdog and WLDI Timing
SUMMIT MICROELECTRONICS, Inc.
SMS45
Preliminary Information
PIN DESCRIPTIONS (CONTINUED)
A1,A2 (6, 7) A1 and A2 are the address inputs. When addressing the SMS45 memory or configuration registers the address inputs distinguish which one of four possible devices sharing the common bus is being addressed. SDA (9) SDA is the serial data input/output pin. It should be tied to VDD_CAP through a pull-up resistor. SCL (10) SCL is the serial clock input. It should be tied to VDD_CAP through a pull-up resistor. PUP#1, PUP#2, PUP#3 (4, 5, 13) These are the power-up permitted (PUP) active low open drain outputs. The PUP pins are used when the SMS45 is programmed to provide the cascade sequencing of LDOs or DC/DC converters (see Figures 1 and 5 for illustrations of cascading). Each delay is independently enabled and programmable for its duration (configuration register 7). If all PUP# outputs are enabled the order of events would be as follows: V0 above threshold then delay to PUP#1 turning on; V1 above threshold then delay to PUP#2 turning on; V2 above threshold then delay to PUP#3 turning on. The delays are programmable.
SUMMIT MICROELECTRONICS, Inc.
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SMS45
Preliminary Information
DEVICE OPERATION
V0 VPTH0
tPRTO RESET# tPDLY1 PUP1#
V1
VPTH1
tPDLY2 PUP2#
V2
VPTH2
tPDLY3 PUP3#
V3
2047 Fig05
Figure 5. VX Input and Resulting PUP# Cascade (RESET# set to trip on V3 Undervoltage)
VPTH0 V0 50ms
PUP1#
V1
PUP2#
V2
VPTH2 50ms
PUP3#
2047 Fig06
Figure 6. Timing with Register 7 Contents 22HEX
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SMS45
Preliminary Information
DEVICE OPERATION (CONTINUED)
Cascading Enabled
V0 >VPTH? Yes tPDLY1
No
Turn On PUP#1
V1 >VPTH? Yes tPDLY2
No
Turn On PUP#2
V2 >VPTH? Yes tPDLY3
No
Turn On PUP#3
2047 Fig07
Figure 7. Cascade Flow Chart
SUMMIT MICROELECTRONICS, Inc.
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SMS45
Preliminary Information
CONFIGURATION REGISTERS
SUPPLY AND MONITOR FUNCTIONS
The V0, V1, V2, and V3 inputs are internally diode-ORed so that any one of the four can act as the device supply. The RESET# output will be guaranteed true so long as one of the four pins is at or above 1V. Note: for performing a memory operation (Read or Write) and to have the ability to change configuration register contents at least one supply input must be above 2.7V. Read/Write operations require a 0.1F capacitor from the VDD_CAP node to GND. For optimum performance connect capacitors from each of the Vx inputs to GND. Locate the capacitors as physically close to the SMS45 as possible. If cascading is enabled, the designer must insure V0 is the primary supply and is the first to become active. Associated with each input is a comparator with a programmable threshold for detection of under-voltage or overvoltage conditions on any of the four supply inputs. The threshold can be programmed in 5mV increments anywhere within the range of 0.6V to 1.875V or 15mV increments within the range of 1.8V to 5.625V. Configuration registers 0, 1, 2, and 3 adjust the thresholds for V0, V1, V2, and V3 respectively. If the value contained in any register is all zeroes, the corresponding threshold will be 0.6V. If the contents were low range 05HEX the threshold would then be 0.625V [0.6V + (5 x 0.005V)]. All four registers are configured as 8-Bit registers.
D7 MSB 1 0 0
D6 1 0 0
D5 1 0 0
D4 1 0 0
D3 1 0 0
D2 1 0 1
D1 1 0 1
D0 LSB 1 0 0
Action Highest threshold adjustment = 5.625V (High Range) Lowest threshold adjustment = 0.6V (Low Range) Threshold = 0.6V + (6x0.005V) = 0.625V (e.g.)
Table 1. Configuration Registers 0, 1, 2, and 3
RESET FUNCTION AND THRESHOLD RANGE
The reset output has four programmable sources for activation. Configuration register 4 is used for selecting the activation source (D7:4), which can be any combination of V0, V1, V2 and V3. A monitor input can be programmed to activate on either an under-voltage or over-voltage condition. The low-order four bits of configuration register 5 program these options. The reset threshold voltage range for V0 to V3 can be set for 5mV increments below 1.875V (low Range = "0") or for 15mV increments above 1.8V (high range = "1") using Bits D3:0. The RESET# output will become active when triggered by a selected activation source such as an under-voltage
D7 MSB X D6 X D5 X D4 X D3 V3 D2 V2 D1 V1 D0 LSB V0 Action
condition on V1. When this condition ceases, the RESET# output will remain active for tPRTO (programmable reset time-out). This reset time-out interval takes priority over the PUP outputs for use of the timer. The RESET# output has two hardwired sources for activation: the MR# input, and the expiration of the Watchdog timer. RESET# will remain active so long as MR# is low, and will continue driving the RESET# output for tPRTO (programmable reset time out) after MR# returns high. The MR# input cannot be bypassed or disabled. Refer to Figures 2, 3 and 4 for a detailed illustration of the relationships among the affected signals.
Voltage Threshold Range Select RESET Trigger Enable 0 1 0 1 0 1 0 1 Low Range High Range
The status of the four supplies is available at any time over the I2C bus in the high order configuration bits of register 5 (Table 3). A "1" in a bit location indicates a fault on that supply.
Table 2. Configuration Register 4
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SMS45
Preliminary Information
CONFIGURATION REGISTERS (CONTINUED)
D3 MSB V3 0 D2 V2 0 D1 V1 0 D0 LSB V0 0
Action Writing a 0 enables undervoltage detection for the selected V input Writing a 1 enables overvoltage detection for the selected V input
D7 MSB
D6
D5
D4 Read Only x x x x
D3 Read Only x x x x Action tPRTO = 25ms tPRTO = 50ms tPRTO = 100ms tPRTO = 200ms
Read1 RTO1 RTO0 Only 0 0 0 1 1 0 1 0 1 0 0 0
1
1
1
1
Table 3. Configuration Register 5 (D0 through D3)
WATCHDOG TIMER
The Watchdog Timer will generate a reset if it times out. It can be cleared by a high-to-low transition on WLDI and restarted. If the Watchdog times out RESET# will be driven low until tPRTO at which time it will return high. Refer to Figure 4 which illustrates the action of RESET# with respect to the Watchdog timer and the WLDI input. If WLDI is held low the timer will free-run generating a series of resets.
D7 MSB V3 0 1 D6 V2 0 1 D5 V1 0 1 D4 LSB V0 0 1
Table 5. Configuration Register 6 (D3 through D7) Note 1 - Read Only bit D7 is set to a 0. Read only bits D4 and D3 are revision control and the value indicates the status code of the device (ie. 01 is status code 1). D2 Action OFF 400ms 800ms 1600ms 3200ms 6400ms WD2 0 0 1 1 1 1 D1 WD1 0 1 0 0 1 1 D0 LSB WD0 0 1 0 1 0 1
Action Reading a 1 indicates a supply fault
Table 6. Configuration Register 6 (D0, D1, D2) Table 4. Configuration Register 5 (D4 through D7) When the Watchdog times out RESET# will be generated. When RESET# returns high (after tPRTO) the timer is reset to time zero. Register 6 is also used to set the programmable reset timeout period (tPRTO) and to select the cascade option. Cascade Delay Programming The cascade delays are programmed in register 7. Bit 7 of register 6 must be set to a 0 in order to enable the cascading of the PUP# outputs. Cascading will not commence until V0 is above its programmed threshold. Each PUP# (-3, -2 and -1) is delayed according to the states of its Bit 1 and Bit 0 as indicated in Table 9. Refer to Figures 1 and 5 for the detailed timing relationship of the programmable power-on cascading. The delay from VPTH0 until PUP#1 low is tPDLY1. There is a similar tPDLYX delay for V1 to PUP#2 and for V2 to PUP#3. They are programmed in register 7. Cascading will always occur as indicated in the flow chart (Figure 7).
SUMMIT MICROELECTRONICS, Inc.
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SMS45
Preliminary Information
CONFIGURATION REGISTERS (CONTINUED)
D7 MSB D6
D5 D4 D3 D2 D1 D0 LSB Bit 0
Address Select Lock x x 0 1 AS0 0 1 x x
PUP#3
PUP#2 Bit 1 Bit 0
PUP#1 Bit 1
2047 Table08 3.0
Action DTI = 1010, responds only when address bits = A2 & A1 logic states DTI = 1011, responds only when address bits = A2 & A1 logic states Config. Reg. Read/Write enabled Config. Reg. Read/Write locked out
1 2047 Table07 3.0
Bit 1
Bit 0
Table 8. Configuration Register 7 (D5 through D0)
Bit 1 0 0 1 1
Bit 0 0 1 0 1
tPDLYX 0ms (no) Delay 25ms Delay 50ms Delay 100ms Delay
2047 Table09 1.0
Note 1 - Setting this bit will cause a permanent Read/Write Lock out.
Table 7. Configuration Register 7 (D7, D6)
Table 9. PUP Delays, Configuration Register 7
DEVELOPMENT HARDWARE & SOFTWARE
SMX3200 PROGRAMMER
The end user can use the summit SMX3200 programming cable and software that have been developed to operate with a standard personal computer. The programming cable interfaces directly between a PC's parallel port and the target application. The application's values are entered via an intuitive graphical user interface employing dropdown menus. The latest revisions of all software and an application brief describing the SMX3200 is available from the website (www.summitmicro.com). The Windows GUI software will generate the data and send it in I2C serial bus format so that it can be directly downloaded to the SMS45 via the programming Dongle and cable. An example of the connection interface is shown in Figure 8. When design prototyping is complete, the software can generate a HEX data file that should be transmitted to Summit for approval. Summit will then assign a unique customer ID to the HEX code and program production devices before the final electrical test operations. This will ensure proper device operation in the end application.
Top view of straight 0.1" x 0.1 closed-side connector. SMX3200 interface cable connector. Pin 10, Reserved Pin 8, Reserved Pin 6, MR# Pin 4, SDA Pin 2, SCL Pin 9, 5V Pin 7, 10V Pin 5, Reserved Pin 3, GND Pin 1, GND
D1 1N4148 VDD_CAP
SMS45
MR# SDA SCL
10 8 6 4 2
9 7 5 3 1
C1 0.1F
GND
Figure 8. SMX3200 Programmer I2C serial bus connections to program the SMS45.
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SMS45
Preliminary Information
I2C PROGRAMMING INFORMATION
MEMORY OPERATION
Data for the configuration registers and the memory array are read and written via an industry standard two-wire interface. The bus was designed for two-way, two-line serial communication between different integrated circuits. The two lines are a serial data line (SDA) and a serial clock line (SCL). The SDA line must be connected to a positive supply by a pull-up resistor, located somewhere on the bus. See Memory Operating Characteristics: Table 10 and Figure 9.
Symbol fSCL tLOW tHIGH tBUF tSU:STA tHD:STA tSU:STO tAA tDH tR tF tSU:DAT tHD:DAT TI tWR Parameter SCL clock frequency Clock low period Clock high period Bus free time (1) Star t condition setup time Star t condition hold time Stop condition setup time Clock edge to valid output Data Out hold time SCL and SDA rise time (1) SCL and SDA fall time (1) Data In setup time Data In hold time Noise filter SCL and SDA Write cycle time Noise suppression 250 0 100 5 SCL low to valid SDA (cycle n) SCL low (cycle n+1) to SDA change Before new transmission
Input Data Protocol The protocol defines any device that sends data onto the bus as a transmitter and any device that receives data as a receiver. The device controlling data transmission is called the Master and the controlled device is called the Slave. In all cases the SMS45 will be a Slave device, since it never initiates any data transfers. One data bit is transferred during each clock pulse. The data on the SDA line must remain stable during clock high time because changes on the data line while SCL is high will be interpreted as start or stop condition.
MIN 0 4.7 4.0 4.7 4.7 4.0 4.7 0.2 0.2 1000 300 3.5 TYP MAX 100 Units kHz s s s s s s s s ns ns ns ns ns ms
Conditions
Note (1): These values are guaranteed by design.
2047 Table10 4.0
Table 10. I C Operating Characteristics
tR tF tHIGH tLOW
2
SCL
tSU:STA tHD:DAT tSU:DAT tSU:STO
tHD:STA
tBUF
SDA In
tAA
tDH
SDA Out
2047 Fig09
Figure 9. I2C Operating Characteristics
SUMMIT MICROELECTRONICS, Inc. 2079 1.2 05/24/04
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SMS45
Preliminary Information
I2C PROGRAMMING INFORMATION (CONTINUED)
START and STOP Conditions When both the data and clock lines are high the bus is said to be not busy. A high-to-low transition on the data line, while the clock is high, is defined as the Start condition. A low-to-high transition on the data line, while the clock is high, is defined as the Stop condition. See Figure 10.
D7 MSB D6 D5 D4 D3 D2 D1 D0 LSB R/W x
Address Bits Device Type SMS45 1 1 0 0 0 0 1 1 1 0 1 x Bus x MSB x
Configuration Register Memor y (default) Alternate Memor y
2047 Table11 1.0
START Condition SCL
STOP Condition
1
Table 11. Slave Addresses Read/Write Bit The last bit of the data stream defines the operation to be performed. When set to 1 a Read operation is selected; when set to 0 a Write operation is selected.
SDA In
2047 Fig10
Figure 10. START and STOP Conditions
WRITE OPERATIONS
Acknowledge (ACK) Acknowledge is a software convention used to indicate successful data transfers. The transmitting device, either the Master or the Slave, will release the bus after transmitting eight bits. During the ninth clock cycle the receiver will pull the SDA line low to Acknowledge that it received the eight bits of data. The Master will leave the SDA line high (NACK) when it terminates a read function. The SMS45 will respond with an Acknowledge after recognition of a Start condition and its slave address byte. If both the device and a write operation are selected the SMS45 will respond with an Acknowledge after the receipt of each subsequent 8-Bit word. In the READ mode the SMS45 transmits eight bits of data, then releases the SDA line, and monitors the line for an Acknowledge signal. If an Acknowledge is detected and no Stop condition is generated by the Master, the SMS45 will continue to transmit data. If a NACK is detected the SMS45 will terminate further data transmissions and await a Stop condition before returning to the standby power mode. Device Addressing Following a Start condition the Master must output the address of the Slave it is accessing. The most significant four bits of the Slave address are the device type identifier/address. For the SMS45 the default is 1010BIN. The next two bits are the Bus Address. The next bit (the 7th) is the MSB of the memory address. The SMS45 allows two types of Write operations: byte Write and page Write. A byte Write operation writes a single byte during the nonvolatile write period (tWR). The page Write operation, limited to the memory array, allows up to 16 bytes in the same page to be written during tWR. Byte Write After the Slave address is sent (to identify the Slave device and select either a Read or Write operation), a second byte is transmitted which contains the low order 8 bit address of any one of the 512 words in the array. Upon receipt of the word address the SMS45 responds with an Acknowledge. After receiving the next byte of data it again responds with an Acknowledge. The Master then terminates the transfer by generating a Stop condition, at which time the SMS45 begins the internal Write cycle. While the internal Write cycle is in progress the SMS45 inputs are disabled and the device will not respond to any requests from the Master. Page Write (memory only) The SMS45 is capable of a 16-byte page Write operation. It is initiated in the same manner as the byte Write operation, but instead of terminating the Write cycle after the first data word the Master can transmit up to 15 more bytes of data. After the receipt of each byte the SMS45 will respond with an Acknowledge. The SMS45 automatically increments the address for subsequent data words. After the receipt of each word the low order address bits are internally incremented by one.
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SMS45
Preliminary Information
I2C PROGRAMMING INFORMATION (CONTINUED)
The high order bits of the address byte remain constant. Should the Master transmit more than 16 bytes, prior to generating the Stop condition, the address counter will rollover and the previously written data will be overwritten. As with the byte Write operation, all inputs are disabled during the internal Write cycle. Refer to Figure 11 for the address, Acknowledge, and data transfer sequence.
Master SDA Slave
S T A R Device Type Bus T Address Address
Typical Write Operation (Standard memory device type)
A AA A AA AA 7 65 4 32 10 A C K A C K DDDDDDDD 76543210 A C K
S T O P
1010
R BB AAA/ 218W
Up to 15 additional bytes can be written before issuing the stop. N AS CT KO P
Master SDA Slave
S T A R T
Typical Reading Operation (Alternate memory device type)
BB R AAA/ 218W A C K AAAAAAAA 76543210
S T AA CR KT
1 01 1
1 01 1
BBAR AA / 218W A C K
DDDDDDDD 76543210
Master SDA Slave
S T A R T
Writing Configuration Registers
R BB AAX/ W 21 A C K
S T O P DDDDDDDD 76543210 A C K A C K
1 00 1
CCCCCCCC 76543210
Master SDA Slave
S T A R T
Reading the Configuration Register
BB R AAX/ 21 W A C K CCCCCCCC 76543210
S T AA CR KT
N AS CT KO P
1 00 1
1 00 1
BB R AAX/ 21 W A C K
DDDDDDDD 76543210
2047 Fig11
Figure 11. Read and Write Operations
SUMMIT MICROELECTRONICS, Inc. 2079 1.2 05/24/04
15
SMS45
Preliminary Information
I2C PROGRAMMING INFORMATION (CONTINUED)
Acknowledge Polling When the SMS45 is performing an internal Write operation it will ignore any new Start conditions. Since the device will only return an acknowledge after it accepts the Start the part can be continuously queried until an acknowledge is issued, indicating that the internal Write cycle is complete. See the flow chart for the proper sequence of operations for polling. Current Address Read (memory only) The SMS45 contains an internal address counter which maintains the address of the last word accessed, incremented by one. If the last address accessed (either a Read or Write) was to address location n, the next Read operation would access data from address location n+1 and increment the current address pointer. When the SMS45 receives the Slave address field with the R/W bit set to 1 it issues an acknowledge and transmits the 8-Bit word stored at address location n+1. The current address byte Read operation only accesses a single byte of data. The Master sets the SDA line to NACK and generates a stop condition. At this point the SMS45 discontinues data transmission. Random Address Read (Register and Memory) Random address Read operations allow the Master to access any memory location in a random fashion. This operation involves a two-step process. First, the Master issues a write command which includes the start condition and the Slave address field (with the R/W bit set to Write), followed by the address of the word it is to Read. This procedure sets the internal address counter of the SMS45 to the desired address. After the word address acknowledge is received by the Master it immediately reissues a Start condition, followed by another Slave address field with the R/W bit set to READ. The SMS45 will respond with an Acknowledge and then transmit the 8 data bits stored at the addressed location. At this point the Master sets the SDA line to NACK and generates a Stop condition. The SMS45 discontinues data transmission and reverts to its standby power mode. Sequential READ (Memory Only) Sequential Reads can be initiated as either a current address Read or random access Read. The first word is transmitted as with the other byte Read modes (current address byte Read or random address byte Read); however, the Master now responds with an Acknowledge, indicating that it requires additional data from the SMS45. The SMS45 continues to output data for each Acknowledge received. The Master terminates the sequential Read operation by responding with a NACK, and issues a Stop condition. During a sequential Read operation the internal address counter is automatically incremented with each Acknowledge signal. For Read operations all address bits are incremented, allowing the entire array to be read using a single Read command. After a count of the last memory address the address counter will rollover and the memory will continue to output data.
Write Cycle In Progress
Issue Start Issue Stop Issue Slave Address and R/W = 0
ACK Returned Yes
No
Next Operation a Write? Yes Issue Address
No
Issue Stop
Proceed With Write
Await Next Command
2047 Fig12
Figure 12. Write Flow Chart
READ OPERATIONS
Read operations are initiated with the R/W bit of the identification field set to 1. There are two different Read options: 1. Current Address Byte Read, and 2. Random Address Byte Read.
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2079 1.2 05/24/04
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SMS45
Preliminary Information
APPLICATIONS
MR# VDD_CAP D6 DIODE 1 3 5 7 9 VDD_CAP J1 Gnd SCL Gnd3 SDA Rsrv 5 MR# +10V Rsrv 8 +5V Rsrv 10 2 4 6 8 10 R4 10K RESET# WLDI VDD_CAP 9 10 11 15
I2C SMX3200
U1 6 7 1
RESET#
MR#
SDA SCL
VDD_CAP
12
C1 0.01uF
C2 0.01uF
C3 0.01uF
C4 0.01uF
VDD_CAP
0.1uF C5
Figure 13. Typical applications schematic, the SMX3200 programmer has internal SDA and SCL pullup resistors.
8
GND
V0 V1 V2 V3
16 2 3 14
WLDI
R1 10K 4 5 13
R2 10K
R3 10K PUP#1 PUP#2 PUP#3
A1 A2
V0 V1 V2 V3
SM S45
PUP#1 PUP#2 PUP#3
SUMMIT MICROELECTRONICS, Inc.
2079 1.2 05/24/04
17
SMS45
Preliminary Information
DEFAULT CONFIGURATION REGISTER SETTINGS - SMS45GC-230
R e g ister R 00 R 01 R 02 R 03 R 04 R 05 R 06 R 07
C o n ten ts 56 28 A0 14 F3 X0 4D 6A
F u n ctio n V 0 thre sh old set to 3.0 90 V V 1 thre sh old set to 2.4 00 V V 2 thre sh old set to 1.4 00 V V 3 thre sh old set to 0.7 00 V R ese t T rigg er sou rce se t for all ch ann els, V 0 , V 1 set to h ig h ran ge a nd V 2 , V 3 set to lo w rang e U p per b its are volatile statu s in dica tion of inp ut su pply con ditio n. V 0, V 1, V 2 an d V 3 se t to m o nitor U V U n der V oltage . R ese t tim eo ut set to 10 0m s, W a tch dog T im er set to 1.6 s. B its D 4 an d D 3 in dica te re vision contro l. E E m e m o ry sla ve ad dress is 10 11, co nfig ura tion registe rs are u nlo cke d, casca ding d ela ys a re a ll 50m s
The default device ordering number is SMS45GC-230, is programmed as described above and tested over the commercial temperature range.
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SMS45
Preliminary Information
PACKAGE
16 PIN SSOP PACKAGE
0.189 - 0.197 (4.80 - 5.00)
Ref. JEDEC MO-137
0.228 - 0.244 (5.79 - 6.20) Inches (Millimeters) Pin 1
0.150 - 0.157 (3.81 - 3.99) 0.053 - 0.069 (1.35 - 1.75) 0.007 - 0.010 (0.18 - 0.25) 0" Min to 8" Max 0.016 - 0.050 (0.41 - 1.27) 0.025 (0.635) 0.008 - 0.012 (0.20 - 0.31) 0.059 MAX (1.50)
0.004 - 0.010 (0.10 - 0.25)
16 Pin SSOP
SUMMIT MICROELECTRONICS, Inc.
2079 1.2 05/24/04
19
SMS45
Preliminary Information
PART MARKING
SUMMIT SMS45G
Summit Part Number
xx
Status Tracking Code (Blank, MS, ES, 01, 02,...) (Summit Use)
Annn AYYWW
Pin 1 Identifier
Date Code (YYWW) Lot tracking code (Summit use) Part Number suffix (Contains Customer specific ordering requirements) Product Tracking Code (Summit use)
Drawing not to scale
ORDERING INFORMATION
SM S45 G C nnn P a r t N u m b e r S u ffix (s e e p a g e 1 8 )
S p e c if ic r e q u ir e m e n t s a r e c o n t a in e d in t h e s u f f ix s u c h a s H e x c o d e , H e x c o d e r e v is io n , e t c .
S u m m it P a r t Num ber Package G =16 Lead SSO P
Tem p Range C = C o m m e r c ia l B la n k = I n d u s t r ia l
NOTICE
NOTE 1 - This is a Preliminary Information data sheet that describes a Summit product currently in pre-production with limited characterization. SUMMIT Microelectronics, Inc. reserves the right to make changes to the products contained in this publication in order to improve design, performance or reliability. SUMMIT Microelectronics, Inc. assumes no responsibility for the use of any circuits described herein, conveys no license under any patent or other right, and makes no representation that the circuits are free of patent infringement. Charts and schedules contained herein reflect representative operating parameters, and may vary depending upon a user's specific application. While the information in this publication has been carefully checked, SUMMIT Microelectronics, Inc. shall not be liable for any damages arising as a result of any error or omission. SUMMIT Microelectronics, Inc. does not recommend the use of any of its products in life support or aviation applications where the failure or malfunction of the product can reasonably be expected to cause any failure of either system or to significantly affect their safety or effectiveness. Products are not authorized for use in such applications unless SUMMIT Microelectronics, Inc. receives written assurances, to its satisfaction, that: (a) the risk of injury or damage has been minimized; (b) the user assumes all such risks; and (c) potential liability of SUMMIT Microelectronics, Inc. is adequately protected under the circumstances. Revision 1.2 - This document supersedes all previous versions. Please check the Summit Microelectronics, Inc. web site at
www.summitmicro.com for data sheet updates.
(c) Copyright 2004 SUMMIT MICROELECTRONICS, Inc. I2C is a trademark of Philips Corporation.
PROGRAMMABLE ANALOG FOR A DIGITAL WORLDTM
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2079 1.2 05/24/04
SUMMIT MICROELECTRONICS, Inc.

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