BP5302XA

DC / DC converter for LCDs BP5302A / BP5302XA The BP5302A and BP5302XA are DC / DC converters for supplying power to liquid crystal display (LCD) panels. The modules supply a negative voltage from a positive power supply. They are available in a single in-line package as an upright (BP5302A) or L-shaped lead (BP5302XA) type. Applications LCD panels in personal computers and word processors Features 1) Wide input voltage range.(+5V to +14V) 2) High accurate output voltage. ( −24±0.75V) 3) High conversion efficiency. (Typ. 80%) 4) Built-in protection circuit. 5) Built-in ON/OFF switch. 6) Compact and light. 7) Available as an upright or L-shaped lead type. Absolute maximum ratings (Ta=25°C) Parameter Input voltage Symbol Limits Unit VIN 15 V Operating temperature range Topr 0~60 °C Storage temperature range Tstg −30~85 °C Electrical characteristics (Unless otherwise noted:Ta=25°C, and R1 and R2 resistors in the measurement circuit of Fig.1 are disconnected) Parameter Input voltage Symbol Min. Typ. Max. Unit VIN 5 − 14 V Conditions Output current IOUT − − 30 mA Output voltage VOUT −23.25 −24.00 -24.75 V VIN=12V, IOUT=20mA Line regulation DV1 − − 0.75 V VIN=5~14V, IOUT=20mA Load regulation DV2 − − 0.5 V VIN=12V, IOUT=0~20mA Ripple nose voltage n1 − − 200 mVP-P VIN=12V, IOUT=20mA Efficiency h 70 80 - % VIN=12V, IOUT=20mA ON / OFF CTL votage when ON VCTL 1.5 − 6.0 V VIN=5~14V VCTL − − 0.5 ON / OFF CTL votage when OFF V VIN=5~14V (Alternatively, when OPEN) ON / OFF CTL current ICTL − − 150 µA VIN=5~14V, VCTL=5V Current consumption when OFF IOFF − − 10 µA VIN=5~14V, VCTL=0V R1 resistance R1 50 − ∞ kΩ VIN=5~14V, VCTL=5V R2 resistance R2 20 − ∞ kΩ VIN=5~14V, VCTL=5V ∗ ∗ Measured with a band width of 20MHz. 1/4 BP5302A / BP5302XA Pin descriptions Pin No. Pin name Function 1 CO Output smoothing capacitor connection pin; connect a lowimpedance capacitor with a recommended capacitance of 47µF between this pin and GND 2 VOUT Output pin 3 Vref Output voltage adjustment pin for contrast; output voltage is adjusted by connecting a resistor between pins 2 and 3 or pins 3 and 4 4, 7 GND Ground pin 8 VCTL Output ON / OFF control pin; output starts when the pin is HIGH level, and stops when the pin is LOW or OPEN 9 VIN Input pin; connect a low-impedance capacitor with a recommended capacitance of 100µF between this pin and GND Measurement circuit and Application example BP5302A / BP5302XA 1 2 3 4 7 8 9 Be sure to use fuse for safety (R1) VIN (R2) ON / OFF SW VOUT + C2 + C1 VCTL GND GND Fig.1 C1 : 100µF / 16V (Low impedance) C2 : 47µF / 35V (Low impedance) R1, R2 : Resistors for adjusting output voltage (Disconnected during test measurement) Operation notes (1) Place I/O external capacitors as near as possible to the connection pins. In particular, make sure to minimize the impedance between the input-side capacitor (C1) and pin 9. (Reference value: A length less than 50mm is recommended for a copper foil of 1.0mm wide and 35µF thick.) (2) Avoid frequent switching using the ON/OFF CTL pin (5 times per second at the maximum). (3) R1 and R2 resistors, which are used for changing the output voltage, are usually not required. 2/4 BP5302A / BP5302XA Electrical characteristic curves −25 ∗1. R1>50kΩ R1 2pin − 3pin R2>20kΩ R2 3pin − 4pin ∗2. Note that output voltage decreases with increasing output current when the input voltage VIN is low. ( −20 ) −15 −10 Unusable range −5 0 10 20 30 −31 R1 (R2= ∞) −30 −29 −28 −27 −26 −25 −24 −23 −22 −21 −20 −19 −18 R2 (R1= ∞) −17 OUTPUT CURRENT : IO (mA) −20 VIN=12V Io=0mA VIN=12V IO=0mA −19 OUTPUT VOLTAGE : VO (V) OUTPUT VOLTAGE : VO (V) Ta=60°C OUTPUT VOLTAGE : VO (V) VIN=14V VIN =5 V −30 −18 −17 −16 −15 −14 −13 −12 −11 100k 1M 10M 10 FEED BACK RESISTANCE : R1, R2 (Ω) Fig.2 Derating curve 20 30 40 50 60 70 80 90 100 FEED BACK RESISTANCE : R2 (kΩ) Fig.3 Output voltage vs. Feedback resistance (R1, R2) Fig.4 Output voltage vs. Feedback resistance (R2