at1738 Aimtron Technology, at1738 Datasheet
at1738
Related parts for at1738
at1738 Summary of contents
Page 1
... The voltage detector with adjustable detected voltage-point and delay-time monitors the input supply voltage to prevent the improper shutdown of the system power application. The AT1738 is available in a 24-pin thin QFN package which is 4mm x 4mm with a maximum thickness of 0.8mm for ultra-thin LCD panel design. ...
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... AGND CONTROL SS FB INL VDD LINEAR OUTL REGULATOR FBL POSITIVE DRVP CHARGE-PUMP CONTROL FBP DLP VPSRC GATE-ON SWCTL GON PULSEWIDTH MODULATOR CONTROL DRN VSEN POSOP VOLTAGE DETECTOR PG OUTOP DLVD WWW: Email: 2 AT1738 Marking AT1738N VMAIN VP VGON VMAIN VCOM http://www.aimtron.com.tw service@aimtron.com.tw ...
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... Analog Ground. Exposed pad should solder to analog ground plane for AGND Pad the optimal power dissipation. 7F, No.9,PARK AVENUE. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 Fax: 886-3-563-0879 8/01/2008 REV: 0.8 Preliminary Product Information LCD Panel Step-up Converter with Analog Multi-Function Outputs Function http://www.aimtron.com.tw WWW: service@aimtron.com.tw Email: 3 AT1738 ...
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... LCD Panel Step-up Converter with Analog Multi-Function Outputs Rated Value Min. -0.3 -0.3 -0.3 -0.3 -0.3 - -75.0 - -30 -55 - -200 -2 Values Symbol Min. Typ WWW: service@aimtron.com.tw Email: 4 AT1738 Unit Max. V +6.0 +0.3 V +16.0 V +16.0 V +30.0 V 2.0 A +75.0 mA 1349 mW +85 °C +150 °C +260 °C 200 Unit Max. 5.5 V +125 ° ...
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... Buffer configuration 4V, POSOP no load ( OUTOP POSOP VDD T = +25℃ OUTOP POSOP VDD I = 100µA OUTOP I = 5mA OUTOP WWW: Email: 5 AT1738 = 8.5V, PGND = AGND = 0, Values Unit Min. Typ. Max. 2.5 5.5 V 2.1 2.2 2.3 V 200 mV 0.4 1 0.3 0 1000 1200 1400 ...
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... I = 20mA VP GON V = 1.24V FBP V = 1.2V FBP V = 1.5V FBP Falling edge During startup 1.0V DLP During UVLO 2. =1.5V, SWCTL=low DLP V =1.5V, SWCTL=high DLP WWW: Email: 6 AT1738 150 100 150 180 mA 100 150 180 ± V/µs 12 MHz 8 MHz 2.5 5 µA 300 500 mV 1.224 1 ...
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... No.9,PARK AVENUE. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 Fax: 886-3-563-0879 8/01/2008 REV: 0.8 Preliminary Product Information LCD Panel Step-up Converter with Analog Multi-Function Outputs V =1.5V, SWCTL=low DLP =1.5V, SWCTL =high DLP DELAY_VD DLVD WWW: Email: 7 AT1738 10 20 Ω Ω 2.1 2.2 2.3 V 1.04 V -1.0 1.0 % 120k Ω http://www.aimtron.com.tw ...
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... Tel: 886-3-563-0878 Fax: 886-3-563-0879 8/01/2008 REV: 0.8 Preliminary Product Information LCD Panel Step-up Converter with Analog Multi-Function Outputs Boost Efficiency VS. Output Current 0.2 0.25 0.3 0 0.05 WWW: Email: 8 AT1738 Vin=3.0V Vin=4.0V Vin=5.0V Vout=8.5V,FREQ=1.2MHz 0.1 0.15 0.2 0.25 0.3 Output Current(A) http://www.aimtron.com.tw service@aimtron.com.tw ...
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... No.9,PARK AVENUE. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 Fax: 886-3-563-0879 8/01/2008 REV: 0.8 Preliminary Product Information LCD Panel Step-up Converter with Analog Multi-Function Outputs 60 80 100 Boost Load Transient Response CH1:VMAIN(AC) CH4:IL WWW: Email: 9 AT1738 CH3:IMAIN http://www.aimtron.com.tw service@aimtron.com.tw ...
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... Power Off Sequence With VGL CH1:VOUTL CH2:VMAIN CH3:VP CH4:VGL Power Off Sequence With VGON CH1:VOUTL CH2:VMAIN CH3:VP CH4:VGON OPA Small Signal Step Response CH1:POSOP CH2:OUTOP http://www.aimtron.com.tw WWW: service@aimtron.com.tw Email: 10 AT1738 ...
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... CH3:VGON 7F, No.9,PARK AVENUE. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 Fax: 886-3-563-0879 8/01/2008 REV: 0.8 Preliminary Product Information LCD Panel Step-up Converter with Analog Multi-Function Outputs OPA Slew Rate CH1:POSOP CH2:OUTOP http://www.aimtron.com.tw WWW: service@aimtron.com.tw Email: 11 AT1738 ...
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... Typical Application Circuit 7F, No.9,PARK AVENUE. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 Fax: 886-3-563-0879 8/01/2008 REV: 0.8 Preliminary Product Information LCD Panel Step-up Converter with Analog Multi-Function Outputs http://www.aimtron.com.tw WWW: service@aimtron.com.tw Email: 12 AT1738 ...
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... Function Description The AT1738 offers a complete power-supply solution for TFT LCD panels used in LCD monitors and NB LCD panels. The AT1738 consists of a high-performance step-up converter, a low-power charge-pump regulator, a high-performance linear regulator, an operational amplifier, a voltage detector and a logic-controlled gate-on pulse modulator. Step-up Converter The step-up DC-DC converter adopts the PWM current mode control, fixed selectable 640k/1.2MHz switching frequency and an internal 2.0A, 0.2Ω ...
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... LCD Panel Step-up Converter with Analog Multi-Function Outputs charges to VMAIN minus a diode drop. CPP by VMAIN volts. This connects C CPP . The amount of charge transferred to the POS . × (sec µ WWW: Email: 14 AT1738 in CPP exceeds 1.24V. SS http://www.aimtron.com.tw service@aimtron.com.tw ...
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... Figure 3. Voltage Detector Function Block and Timing Chart T DELAY 7F, No.9,PARK AVENUE. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 Fax: 886-3-563-0879 8/01/2008 REV: 0.8 Preliminary Product Information LCD Panel Step-up Converter with Analog Multi-Function Outputs = C × 120 k (sec DLVD WWW: service@aimtron.com.tw Email: 15 AT1738 http://www.aimtron.com.tw ...
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... Gate-On Pulse Modulator The AT1738 includes a gate-on pulse modulator to control gate-on voltage waveform to reduce the flicker on TFT LCD panel. After the VIN exceeds UVLO, once the soft-start periods are complete, fault conditions do not exist, and the VDLP exceeds the turn-on threshold, then the gate-on pulse modulator starts to be active and is controlled by SWCTL ...
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... Power-Up Sequence The AT1738 goes through start-up sequence after power-up. When VIN exceeds UVLO threshold, the internal reference voltage starts to rise. After reference voltage reaches regulation, the step-up converter and linear regulators will start up with the soft-start process. Once the FB voltage reaches the reference voltage, the gate-on pulse modulator delay block is also enabled ...
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... The output voltages of step-up converter, positive charge-pump regulator and linear regulators are set by each resistive voltage-divider as the Typical Application Circuit shown. The AT1738 applies a 1.240V feedback reference voltage at FB pin of step-up converter, and the output voltage setting is according to the following equation: VMAIN The feedback reference voltage of positive charge-pump regulator ...
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... The most critical aspect of the layout is the placements of the input bypass capacitors of pin IN, INL, VDD and VPSRC. They must be placed as close as possible to the AT1738 to reduce the input ripple voltage and noise coupling. 2. Power loops on the input and output of the converters should be connected with the shortest and widest traces as possible ...
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... No.9,PARK AVENUE. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 Fax: 886-3-563-0879 8/01/2008 REV: 0.8 Preliminary Product Information LCD Panel Step-up Converter with Analog Multi-Function Outputs Middle ground layer 1 Middle ground layer 2 Bottom-layer WWW: Email: 20 AT1738 http://www.aimtron.com.tw service@aimtron.com.tw ...
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... Analog Multi-Function Outputs DIMENSIONS INCH MAX. MIN. NOM. 0.80 0.027 0.029 0.211 0.0077 0.008 0.30 0.007 0.009 4.075 0.154 0.157 2.80 0.098 0.104 4.075 0.154 0.157 2.80 0.098 0.104 0.02 BSC 0.40 0.012 0.014 http://www.aimtron.com.tw WWW: service@aimtron.com.tw Email: 21 AT1738 MAX. 0.031 0.0083 0.012 0.160 0.110 0.160 0.110 0.016 ...
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... Fax: 886-3-563-0879 22 AT1738 Pb-Free Assembly Large Body Small Body Pkg. thickness Pkg. thickness ≥2.5mm or <2.5mm or Pkg. volume Pkg. volume 3 3 ≥350mm 3° ...