MAX9552EUD+T

19-3858; Rev 3; 10/07 KIT ATION EVALU E L B A AVAIL High-Current VCOM Drive Buffers for TFT LCDs The MAX9550/MAX9551/MAX9552 provide a VCOM source for TFT LCDs. The MAX9550/MAX9551/ MAX9552 source and sink a large current to quickly restore the VCOM voltage, making it ideal for TFT LCDs. The output settles to within 0.1% in less than 2µs. In addition, the MAX9550/MAX9551/MAX9552 directly drive the capacitive load in the VCOM layer of the TFT LCDs without the need for a series resistor. The MAX9550/MAX9551/MAX9552 feature single, dual, and quad channel VCOM amplifiers, respectively. The MAX9550/MAX9551/MAX9552 can drive up to 800mA of peak current per channel and operate up to 20V. The devices feature soft-start to reduce inrush current, output short-circuit protection, and thermal shutdown. The MAX9550 is available in a space-saving 5-pin thin SOT23 package, and an 8-pin µMAX® package with an exposed paddle. The MAX9551 is available in an 8-pin µMAX package with an exposed paddle. The MAX9552 is available in a 14-pin TSSOP package. All devices are specified over the -40°C to +85°C temperature range. Applications TFT-LCD Panels Instrument Control Voltage Sources Features ♦ Operates Up To 20V ♦ 800mA Peak Output Current ♦ Settles to Within 0.1% of VOUT in Less than 2µs ♦ Excellent Load Regulation ♦ Thermal-Shutdown Protection ♦ Short-Circuit Protection to Both Rails ♦ Soft-Start to Reduce Inrush Current Ordering Information PART AMPS PIN-PACKAGE 5 Thin SOT23-5 PKG CODE TOP MARK Z5-1 ADSG MAX9550EZK+T 1 MAX9550EUA+ 1 8 µMAX-EP* U8E-2 AABA MAX9551EUA+ 2 8 µMAX-EP* U8E-2 — MAX9552EUD+ 4 14 TSSOP-EP* U14E-3 — Note: All devices specified over the -40°C to +85°C operating temperature range. +Denotes lead-free package. *EP = Exposed paddle. Pin Configuration appears at end of data sheet. Typical Operating Circuit 16V SUPPLY VDD MAX9550 VREF TFT LCD IN+ OUT IN- 1µF TFT-LCD CAPACITANCE GND µMAX is a registered trademark of Maxim Integrated Products, Inc. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX9550/MAX9551/MAX9552 General Description MAX9550/MAX9551/MAX9552 High-Current VCOM Drive Buffers for TFT LCDs ABSOLUTE MAXIMUM RATINGS Supply Voltage (VDD to GND) ................................-0.3V to +22V Any Other Pin to GND ................................-0.3V to (VDD + 0.3V) IN+/IN- (current) ...............................................................±20mA OUT, OUT_ (current)................................................................1A Continuous Power Dissipation (TA = +70°C) 5-Pin Thin SOT23 (derate 2.7mW/°C above +70°C) ...219.1mW 8-Pin µMAX (derate 10.3mW/°C above +70°C) ........824.7mW 14-Pin TSSOP (derate 20.8mW/°C above +70°C) .....1667mW Operating Temperature Range ...........................-40°C to +85°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10s) .................................+300°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. ELECTRICAL CHARACTERISTICS (VDD = 16V, GND = 0V, VCM = VOUT = VDD / 2, CL = 1µF, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS 20 V DC CHARACTERISTICS VDD Inferred from PSRR test and transient load test Quiescent Current ICC Per channel 2 4 mA Low Output Voltage VOL IL = -4mA 0.04 0.1 V High Output Voltage VOH IH = +4mA VDD - 0.04 VDD - 0.1 V Input Offset Voltage VOS mV Supply Voltage Range Input Bias Current 7 +1 +10 IB -10 0.01 1 RIN 1 µA Input Resistance Common-Mode Input Voltage CMVR Inferred from CMRR 2 Common-Mode Rejection Ratio CMRR 2V ≤ VIN ≤ (VDD - 2V) 80 96 dB Power-Supply Rejection Ratio PSRR VOUT = 3.5V, VDD = 7V to 16V 80 96 dB VDD = 7V, VOUT = 3.5V, guaranteed by load, regulation test 55 Continuous Output Current IO Output Load Regulation LR1 Output Load Regulation LR2 MΩ VDD - 2 mA IOUT = 0mA to 50mA 6 13 IOUT = 0mA to -50mA 6 13 IOUT = 0mA to -55mA 6.5 15 IOUT = 0mA to 55mA 6.5 15 VDD = 7V, VOUT = 3.5V V mV mV Thermal Shutdown +160 °C Thermal Hysteresis 15 °C 2 _______________________________________________________________________________________ High-Current VCOM Drive Buffers for TFT LCDs (VDD = 16V, GND = 0V, VCM = VOUT = VDD / 2, CL = 1µF, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN tS Settling to 0.1% of VOUT, IL = 0 to 600mA, CL = 1µF, RS = 2.2Ω, CS = 0.1µF (Figure 1) TYP MAX UNITS AC CHARACTERISTICS Settling Time Input Capacitance CIN Transconductance gm Transient Output Current IOUTMAX 2.0 µs 1.5 pF IOUT = ±50mA 13 IOUT = ±500mA 42 AV = 1 VDD = 7V, VIN = 1.5V pulse for 100µs ±200 ±290 VDD = 16V, VIN = 1.5V pulse for 100µs ±600 ±830 S mA Note 1: All devices are 100% production tested at TA = +25°C. All temperature limits are guaranteed by design. Typical Operating Characteristics (VDD = 16V, GND = 0V, VCM = VOUT = VDD / 2, CL = 1µF, TA = +25°C, unless otherwise noted.) 0.5 VOS (mV) 0.3 0.2 0.1 0 0.2 0.1 0 TA = +85°C TA = +25°C -0.1 -0.2 -0.1 50 TRANSCONDUCTANCE (S) 0.4 TA = -40°C 0.3 60 MAX9550 toc02 0.4 VOS (mV) 0.6 MAX9550 toc01 0.5 TRANSCONDUCTANCE vs. OUTPUT CURRENT INPUT OFFSET VOLTAGE DEVIATION vs. TEMPERATURE MAX9550 toc03 INPUT OFFSET VOLTAGE DEVIATION vs. SUPPLY VOLTAGE TA = -40°C 40 TA = +25°C 30 20 TA = +85°C 10 -0.3 -0.2 -0.4 5 10 15 VDD (V) 20 25 0 -50 -25 0 25 50 TEMPERATURE (°C) 75 100 -600 -400 -200 0 200 400 600 OUTPUT CURRENT (mA) _______________________________________________________________________________________ 3 MAX9550/MAX9551/MAX9552 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (continued) (VDD = 16V, GND = 0V, VCM = VOUT = VDD / 2, CL = 1µF, TA = +25°C, unless otherwise noted.) SUPPLY CURRENT vs. TEMPERATURE TA = +25°C 2.0 1.5 TA = -40°C 1.0 3.5 SUPPLY CURRENT (mA) 2.5 MAX9550 toc05 MAX9550 toc04 TA = +85°C 3.0 LOAD TRANSIENT (±600mA) 4.0 3.0 2.0 1.5 VOUT 50mV/div AC-COUPLED 0.5 0 0 10 15 20 25 -50 -25 0 25 50 75 2µs/div 100 TEMPERATURE (°C) SUPPLY VOLTAGE (V) STARTUP WAVEFORM MAX9550 toc07 SHORT-CIRCUIT WAVEFORMS ICC 200mA/div MAX9550 toc08 5 IOUT 200mA/div IOUT 200mA/div VCC 10V/div VOUT 5V/div IN+ 5V/div VOUT 5V/div VCC 5V/div 5ms/div 4 IOUT 500mA/div 2.5 1.0 0.5 RS = 2.2Ω, CL = 1µF, CS = 0.1µF 20µs/div _______________________________________________________________________________________ MAX9550 toc06 SUPPLY CURRENT vs. SUPPLY VOLTAGE SUPPLY CURRENT (mA) MAX9550/MAX9551/MAX9552 High-Current VCOM Drive Buffers for TFT LCDs High-Current VCOM Drive Buffers for TFT LCDs PIN MAX9550 MAX9551 MAX9552 NAME FUNCTION THIN SOT23 µMAX 1 6 — — OUT VCOM Output 2 4 4 11 GND Ground 3 3 — — IN+ Positive Input 4 2 — — IN- Negative Input 5 7 8 4 VDD Positive Supply Input — — 1 1 OUTA VCOM Output A — — 3 3 INA+ Positive Input A — — 2 2 INA- Negative Input A — 1, 5, 8 — — N.C. No Connection. Not internally connected. — — 5 5 INB+ Positive Input B — — 6 6 INB- Negative Input B — — 7 7 OUTB VCOM Output B — — — 8 OUTC VCOM Output C — — — 9 INC- Negative Input C — — — 10 INC+ Positive Input C — — — 12 IND+ Positive Input D — — — 13 IND- Negative Input D — — — 14 OUTD — EP EP EP EP VCOM Output D Exposed Paddle. EP is internally connected to GND. Connect EP to GND. _______________________________________________________________________________________ 5 MAX9550/MAX9551/MAX9552 Pin Description MAX9550/MAX9551/MAX9552 High-Current VCOM Drive Buffers for TFT LCDs Detailed Description The MAX9550/MAX9551/MAX9552 operational transconductance amplifiers (OTA) hold the VCOM voltage stable while providing the ability to source and sink a high current quickly (800mA typ) into a capacitive load such as the backplane of a TFT-LCD panel. The output settles to within 0.1% in less than 2µs. The fast settling time is achieved by increasing the transconductance of the buffer as the output current increases (see the Typical Operating Characteristics). In addition, the MAX9550/MAX9551/MAX9552 directly drive the capacitive load in the VCOM layer of the TFT LCD without the need for a series resistor. The MAX9550/MAX9551/MAX9552 unity-gain bandwidth is: GBW = gM / 2πCOUT To insure buffer stability, place a 1µF low-ESR capacitor as close to the OUT pin as possible. However, this value may be reduced if the TFT-LCD panel load provides some of the capacitance and the resistance in series when this capacitance is low. Connect the feedback at OUT using a Kelvin connection at the low-ESR capacitor. Thermal Shutdown with Temperature Hysteresis The MAX9550/MAX9551/MAX9552 are capable of high output currents and therefore, feature thermal-shutdown protection with temperature hysteresis. When the die temperature reaches +160°C, the devices shut down. When the die cools down by 15°C, the devices turn on again. where COUT is the capacitive load at the output and gM is the transconductance. 16V SUPPLY *C1 = 4.7µF *C2 = 0.1µF 16V SUPPLY VDD TEST LOAD MAX9550 VREF IN+ VOUT OUT IN- **RS = 2.2Ω CS = 0.1µF CL = 1µF 0V TO 1.5V AT 50kHz GND *PLACE 4.7µF AND 0.1µF CAPACITORS AS CLOSE TO PIN AS POSSIBLE. **RS INCLUDES THE GENERATOR RESISTANCE. NOTE: PLACE CL AS CLOSE TO OUT PIN AS POSSIBLE AND KELVIN SENSE THE FEEDBACK LOOP CONNECTION AS SHOWN. Figure 1. Settling Time Test Circuit 6 _______________________________________________________________________________________ High-Current VCOM Drive Buffers for TFT LCDs Output Load Capacitor The output load capacitor must have a low ESR value (50mΩ or lower) and it must be placed as close as possible to the OUT pin to ensure buffer stability (see Figure 2). Ceramic capacitors are an excellent choice. Power Supplies and Bypass Capacitors The MAX9550/MAX9551/MAX9552 operate from a 6V to 20V single supply, or from ±3V to ±10V dual supplies. Proper supply bypassing ensures stability while driving high transient loads. The MAX9550/MAX9551/MAX9552 require minimum 4.7µF (C1) and 0.1µF (C2) power-supply bypass capacitors placed as close as possible to the power-supply pin (VDD). See Figure 2. For dualsupply operation, use 4.7µF and 0.1µF bypass capacitors on both supplies (V DD and GND) with each capacitor placed as close as possible to the VDD and GND pins. Layout and Grounding The exposed paddle on the µMAX and TSSOP packages provides a low thermal resistance for heat dissipation. Solder the exposed paddle to a ground plane for best results. Do not route traces under these packages. For dual-supply operation, the exposed paddle (EP) must be electrically connected to the negative supply or it can be left unconnected. 16V SUPPLY *C1 = 4.7µF *C2 = 0.1µF VDD MAX9550 VREF TFT LCD IN+ VOUT OUT IN- CL = 1µF TFT-LCD CAPACITANCE GND *PLACE 4.7µF AND 0.1µF CAPACITORS AS CLOSE TO PIN AS POSSIBLE. NOTE: PLACE CL AS CLOSE TO THE OUT PIN AS POSSIBLE AND KELVIN SENSE THE FEEDBACK LOOP CONNECTION AS SHOWN. Figure 2. Typical TFT-LCD Backplane Drive Circuit _______________________________________________________________________________________ 7 MAX9550/MAX9551/MAX9552 Applications Information High-Current VCOM Drive Buffers for TFT LCDs MAX9550/MAX9551/MAX9552 Pin Configurations TOP VIEW MAX9550 OUT 1 MAX9550 5 VDD GND 2 IN+ 3 N.C. 1 8 IN- 2 7 VDD IN+ 3 6 OUT GND 4 5 N.C. µMAX-EP IN- 4 N.C. THIN SOT23 MAX9552 MAX9551 OUTA 1 8 VDD INA- 2 7 OUTB INA+ 3 6 INB- GND 4 5 INB+ µMAX-EP OUTA 1 14 OUTD INA- 2 13 IND- INA+ 3 12 IND+ VDD 4 11 GND INB+ 5 10 INC+ INB- 6 9 INC- OUTB 7 8 OUTC TSSOP-EP Chip Information PROCESS: BiCMOS 8 _______________________________________________________________________________________ High-Current VCOM Drive Buffers for TFT LCDs THIN SOT23.EPS _______________________________________________________________________________________ 9 MAX9550/MAX9551/MAX9552 Package Information (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) MAX9550/MAX9551/MAX9552 High-Current VCOM Drive Buffers for TFT LCDs Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) 10 ______________________________________________________________________________________ High-Current VCOM Drive Buffers for TFT LCDs 8L, µMAX, EXP PAD.EPS 21-0107 C 1 1 ______________________________________________________________________________________ 11 MAX9550/MAX9551/MAX9552 Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) TSSOP 4.4mm BODY.EPS MAX9550/MAX9551/MAX9552 High-Current VCOM Drive Buffers for TFT LCDs XX XX PACKAGE OUTLINE, TSSOP, 4.40 MM BODY, EXPOSED PAD 21-0108 E 1 1 Revision History Pages changed at Rev 3: 1, 2, 9, 10, 12 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 12 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2007 Maxim Integrated Products is a registered trademark of Maxim Integrated Products, Inc.