MAX1997ETJ Maxim Integrated Products, MAX1997ETJ Datasheet
MAX1997ETJ
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MAX1997ETJ Summary of contents
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... Two Additional Linear-Regulator Controllers (MAX1997 Only) o Programmable Power-Up Sequencing o Multiple Overload Protection with Thermal Shutdown o 1µA Shutdown Current o 32-Pin/20-Pin Thin QFN Packages PART MAX1997ETJ MAX1998ETP TOP VIEW Applications Pin Configurations continued at end of data sheet. Features Ordering Information TEMP RANGE PIN-PACKAGE -40° ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer ABSOLUTE MAXIMUM RATINGS SHDN, FB, FBP, FBN, FB1, FB2, ONDC, IN, ONP, ONN, ON2, TGNDA, TGNDB to GND.............-0.3V to +6V PGND to GND .....................................................................±0.3V LX GND....................................................-0.3V to ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer ELECTRICAL CHARACTERISTICS (continued) = 10V, SHDN = ONDC = FREQ = IN, C (Circuit of Figure 3V DDB Typical values are ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer ELECTRICAL CHARACTERISTICS (continued) = 10V, SHDN = ONDC = FREQ = IN, C (Circuit of Figure 3V DDB Typical values are ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer ELECTRICAL CHARACTERISTICS = 10V, SHDN = ONDC = FREQ = IN 3V DDB (Note 3) PARAMETER IN Supply Range IN Undervoltage Lockout Threshold IN ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer ELECTRICAL CHARACTERISTICS (continued) = 10V, SHDN = ONDC = FREQ = IN 3V DDB (Note 3) PARAMETER NEGATIVE LINEAR-REGULATOR CONTROLLER (REG N) FBN Regulation ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer (Circuit of Figure 3.3V MAIN unless otherwise noted.) STEP-UP REGULATOR EFFICIENCY vs. LOAD CURRENT (V = 9V) MAIN 100 ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer (Circuit of Figure 3.3V MAIN unless otherwise noted.) STEP-UP REGULATOR LOAD TRANSIENT RESPONSE (WITH LAG COMPENSATION, FIGURE 9) MAX1997 toc08 200mA ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer (Circuit of Figure 3.3V MAIN unless otherwise noted.) REG P (GATE-ON VOLTAGE) LOAD REGULATION 0 -0.05 -0.10 -0.15 -0.20 -0.25 0.1 1 LOAD CURRENT ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer (Circuit of Figure 3.3V MAIN unless otherwise noted.) OVERCURRENT PROTECTION RESPONSE TO OVERLOAD DURING STARTUP MAX1997 toc20 20ms/div A: V ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer PIN NAME MAX1997 MAX1998 4 — FB1 ONN 6 3 ONP 7 4 ON2 DRVN 10 7 FBN 11 8 DRVA 12 ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer PIN NAME MAX1997 MAX1998 Gamma Linear-Regulator (REG 2) Base Drive. Open drain of an internal N-channel MOSFET. 19 — DRV2 Connect DRV2 to the base of an external PNP ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer V IN 2. 1000pF R1 R2 10Ω 51.1kΩ R3 150kΩ C1 0.47µF R77 510Ω C12 1µF Q1 R88 12.4kΩ V LOGIC 2.5V C13 10µF LX ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer MAIN DRVA N V SOURCE DRV1 V LOGIC FB1 V SOURCE DRV2 V GAMMA FB2 VDDB FBPB OUTB V VCOM FBNB Figure 2. ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer Table 1. Selected Component List DESIGNATION C2, C13 10µF, 6.3V X5R ceramic capacitors (1206), TDK C3216X5R0J106M C4, C5, C6 4.7µF, 10V X7R ceramic capacitors (1210), Taiyo Yuden LMK352BJ475MF D1 ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer FROM OSCILLATOR Figure 3. Main Step-Up Converter Functional Diagram In addition, all outputs are monitored for fault conditions that last longer than the fault timer period. The device goes ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer V V MAIN DRVP NPN CASCODE TRANSISTOR FBP Figure 4. Using Cascode NPN for Output Voltages > 28V Positive Linear-Regulator Controller, REG P The positive linear-regulator controller is an ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer GATE ENABLE Figure 6. External P-Channel MOSFET Input Switch Control Linear-Regulator Controller REG 2 (MAX1997 Only) The linear-regulator controller REG analog gain block with an open-drain ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer Shutdown ( A logic-low signal on the SHDN pin disables all device functions including the reference. During shutdown, the supply current drops to 0.1µA (typ) to maximize battery life. ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer Table 3. Fault Timer Duration FREQ PIN PFLT PIN* GND GND Unconnected GND IN GND GND Unconnected Unconnected Unconnected IN Unconnected GND IN** Unconnected IN** IN IN** *For MAX1997 ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer SHDN UVLO REFERENCE READY THERMAL FAULT OVERCURRENT FAULT REG 2 FAULT REG 1 FAULT REG P FAULT STEP-UP REGULATOR FAULT REG N FAULT f /128 OSC FREQ PFLT Figure ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer The output capacitor affects the circuit’s stability and output-voltage ripple. A 15µF ceramic capacitor works well in most 1.5MHz applications. Depending on the output capacitor chosen, feedback compensation may ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer The frequencies of the zero and pole for the lead com- pensation are Z_LEAD π ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer P1 R DS(ON OCP 100pF OCN R3 R5 Figure 10. Setting the Overcurrent Threshold Input P-Channel MOSFET Select the input P-channel MOSFET based on current ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer After including the effects of resistor tolerance, com- parator offset, and input voltage variation, the minimum input overcurrent threshold equation is: × × V IN(MIN) × + ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer Increasing the flying capacitor (C ) value increases the X output current capability. Increasing the capacitance indefinitely has a negligible effect on output current capability because the internal switch ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer Stability Requirements The MAX1997/MAX1998 linear-regulator controllers use an internal transconductance amplifier to drive an external pass transistor. The transconductance amplifi- er, the pass transistor, the base-emitter resistor, and the ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer VCOM BUFFER V GAMMA R B 0.47µF C Figure 11. Optimizing VCOM Buffer Drive Current GROUND IMPEDANCE Figure 12. High-Current Loops of Step-Up Regulator ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer 3. GATE SWITCH STEP-UP OCN CONTROL REGULATOR OCP OCN MAX1997 REF MAX1998 REF GND Figure 14. Disabling Input MOSFET Switch Applications ...
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Quintuple/Triple-Output TFT LCD Power Supplies with Fault Protection and VCOM Buffer Pin Configurations (continued) TOP VIEW TGNDB 1 PGND 2 DRV1 3 FB1 4 MAX1997 CT 5 ONN 6 ONP 7 ON2 8 THIN QFN 5mm × 5mm 30 ______________________________________________________________________________________ ...
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... 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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 31 © 2002 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products ...