View AT1731_545651.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

AT1731
Preliminary
2-Channel PWM Controller for LCD Bias General Description
The AT1731 is a PWM DC/DC converter control IC with 2 channel outputs that can directly drive power MOSFET. This IC ia suitable for very small DC/DC converters because of their small and thin package(1.1 mm max.), and high operation frequency (up to 1.0 MHz).
Features
* Low input voltage: 2.5V to 7V * 2-Channels PWM Control: 1 Boost Controller(CH1) 1 Inverting Controller (CH2) * Adjustable Soft start time and maximum duty cycle * Built-in timer latch for short circuit protection: Delay time=216/(Switching frequency) * Built-in under-voltage lockout, thermal shutdown. * High operating frequency: 100kHz to 1MHz
Applications
* LCD Displays Bias * Power Supply for general equipment
Block Diagram
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 1
AT1731
Preliminary
2-Channel PWM Controller for LCD Bias
Pin Configuration
Ordering Information
Part number AT1731 Package TSSOP16 Marking AT1731P -
Pin Description
Symbol Pin No. Descript Symbol Pin No. Descript
FB1 IN1 NC GND PGND GND IN2 FB2
1 2 3 4 5 6 7 8
CH1 error amplifier output
OUT1
9 10 11 12 13 14 15 16
CH1 inverting input to OUT2 error amplifier Don't connect NC Control blocks ground Power blocks ground Control blocks ground CH2 inverting input to error amplifier CH2 error amplifier output VCC REG CT CS2 CS1
CH1 output for NchMOSFET CH2 output for PchMOSFET Don't connect Power Supply Regulated voltage output Oscillator timing capacitor Sotf-start for CH2 Soft-star for CH1
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 2
AT1731
Preliminary
2-Channel PWM Controller for LCD Bias
Absolute Maximum Ratings
Parameter Power Supply Voltage Source Average Current of OUT1 OUT2 Sink Average Current of OUT1 OUT2 Input Voltage to Error Amplifier Continuous power dissipation Operating temperature Junction temperature Storage temperature Lead temperature Condition -- -- -- -- TSSOP16Ta=+25 -- -- -- -- Rated Value Min. Max. +8 -50 -30 -40 50 6.5 500 +85 +125 +150 +300 Unit V mA mA V mW 0 C 0 C 0 C 0 C
Stresses beyond those listed under "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 beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
Recommended Operating Conditions
(Ta=+250C)
Parameter Power supply voltage Oscillation frequency Operating temperature
Symbol VCC fOSC TOP Min. 2.5 100 -30
Values Typ. -500 +25 Max. 7 1000 +85
Unit KHz C
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 3
AT1731
Preliminary
2-Channel PWM Controller for LCD Bias
Electrical Characteristics
(VCC = 3V,Ta =+25, unless otherwise noted.)
Parameter Input Supply Range VCC Lockout Undervoltage
Symbol
Condition 2.5
Values Min. Typ. Max. -7.0
Unit V V V mV % mA mV A mA % % MHz 1.5 V dB 620 kHz V V 2 7 % % V % % mA mA
VCC
UVLO VREF VREF-Line VCC=2.5V to 7.0V Ta =-30 to +85 Duty=50%, fOSC=500KHz VFB = VREG -0.5V VFB = 0.5V Ta =-30 to +85 Ta =-30 to +85 fT VCOM AV fosc CT =150pF CT =150pF CT =150pF Vcc=2.5V to 7V Ta =-30 to +85 VREG CO =0.1F Vcc=2.5V to 7V Ta =-30 to +85 IREG ICS1_2
1.95 2.05 2.15 0.98 1.00 1.02 1 0.5 3.0 5 1.5 3.8 10 -160 -120 2.0 2.5 -80 3.0 20 20 2.0 0.2 480 80 550 1.0 0.5
Reference Voltage Entire device Reference Voltage line-regulation Rference Variation with Temperature Operating Current Input Offset Voltage Source Current (CH1,2) Sink Current(CH1,2) Source current Variation with temperature Sink current Variation with temperature Unity Gain Bandwidth Common Mode Input Voltage Range DC Open Loop Gain Frequency High Level Voltage Sawtooth wave Oscillator (OSC) Low Level Voltage Variation with Power Supply Variation with Temperature Regulated Voltage Variation with Power Regulated Voltage Supply for internal Control Variation with Block Temperature Source Current Soft-Start and Duty Charge Current of Section CS1(Source)
ICC VIO IOH IOL
Error amplifier
2.16 2.20 2.24 1.5 1.5 -40 -1.0 -15
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 4
AT1731
Preliminary
2-Channel PWM Controller for LCD Bias
Charge Current of CS2(Sink) Max. Duty of CH1 Max. Duty of CH2 Invalid TL threshold voltage of CS1 Invalid TL threshold voltage of CS2 Threshold Voltage of FB1 Timer Latch Section Threshold Voltage of (TL) FB2 Start up count Start up time Thermal Shuntdown Threshold Temperature Section Output Section Rise time of OUT1 Rise time of OUT3 Fall time of OUT1 Fall time of OUT2 High Level on Resistance of OUT1 Low Level on Resistance of OUT1 High Level on Resistance of OUT2 Low Level on Resistance of OUT2 ICS3 fOSC=500KHz fOSC=500KHz 80 80 1.0 87 86 0.3 1.32. VTLTH1 VTLTH2 Count TTL TOH tr1 Tr2 tf1 tf2 R1AH R1AL R2AH R2AL CO =1000pF OUT1-GND CO =1000pF VCC-OUT2 CO =1000pF OUT1-GND CO =1000pF VCC-OUT2 IOUT1=-150mA IOUT1=150mA IOUT2=-150mA IOUT2=150mA between between between between 20 20 20 20 2.5 2.5 2.5 2.5 105 1.32 0.3 216 119 140 25 25 25 25 4.0 4.0 4.0 4.0 35 35 35 35 5.5 5.5 5.5 5.5 137 90 90 mA % % V V V V ms
0
C
ns ns ns ns
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 5
AT1731
Preliminary
2-Channel PWM Controller for LCD Bias
Typical Application Circuit
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 6
AT1731
Preliminary
2-Channel PWM Controller for LCD Bias
Package Outline 16-pin TSSOP
SYMBOL A A1 A2 b C D E E1 L e y
MILLIMETERS MIN TYP MAX 1.05 1.10 1.20 0.05 0.10 0.15 1.00 1.05 0.20 0.25 0.28 0.127 4.90 5.075 5.10 6.20 6.40 6.60 4.30 4.40 4.50 0.50 0.60 0.70 0.65 0.076 0 8
MIN 0.041 0.002 0.008 0.193 0.244 0.170 0.020 0
INCHES TYP 0.043 0.004 0.039 0.010 0.005 0.1998 0.252 0.173 0.024 0.026 -
MAX 0.047 0.006 0.041 0.011 0.200 0.260 0.177 0.028 0.003 8
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 7
AT1731
Preliminary
2-Channel PWM Controller for LCD Bias
Reflow Condition (IR/Convection or VPR Reflow)
Reference JEDEC Standard J-STD-020A
Classification Reflow Profiles Convection or IR/Convction
Average Heating Rate(180C to peak) 5C/second max. 120 seconds max. Preheat Temperature(12520C) 10~150 seconds Temperature maintained above 180C 10~20 seconds Time within 5C of actual Peak Temperature Peak Temperature Range(Note 1) 219~225C or 235~240C Cooling Rate 6C /second max. 6 minutes max. Time 25C to Peak Temperature
VPR
10C/second max.
60 seconds 219~225C or 235~240C 10C/second max.
*1 The maximum peak temperatures for IR and VP reflow are depending on package dimensions.
Package Reflow Conditions Pkg. Thickness 2.5mm Pkg. Thickness <2.5mm Pkg. Thickness <2.5mm and and and all bags 3 Pkg. Volume <350 mm3 Pkg. Volume 350 mm Convection 219~225C VPR 219~225C IR/Convection 219~225C Convection 235~240C VPR 235~240C IR/Convection 235~240C
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 8

▲Up To Search▲

Price & Availability of AT1731

	To Download AT1731 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .