MB39A112 Datasheet | Fujitsu Semiconductor Limited

DESCRIPTION The MB39A112 is a 3-channel DC/DC converter IC using pulse width modulation (PWM) , and the MB39A112 is suitable for down-conversion. 3-channel is built in TSSOP-20P package. Each channel can be controlled and soft-start. The MB39A112 contains a constant voltage bias circuit for output block, capable of implementing an efficient high-frequency DC/DC converter. It is ideal for built-in power supply such as ADSL modems. s REATURES - Supports for down-conversion (CH1 to CH3) - Power supply voltage range : 7 V to 25 V - Error amplifier threshold voltage : 1.00 V ± 1% (CH1) : 1.23 V ± 1% (CH2, CH3) - Oscillation frequency range : 250 k Hz to 2.6 MHz - Built-in soft-start circuit independent of loads - Built-in timer-latch short-circuit protection circuit - Built-in totem-pole type output for P-channel MOS FET devices - Built-in constant voltage (VCCO - 5 V) bias circuit for output block s PACKAGE 20-pin plastic TSSOP (FPT-20P-M06) .. .. MB39A112 s PIN ASSIGNMENT (TOP VIEW) CS1 : 1 - INE1 : 2 FB1 : 3 VCC : 4 RT : 5 CT : 6 GND : 7 FB2 : 8 - INE2 : 9 CS2 : 10 20 : VCCO 19 : OUT1 18 : OUT2 17 : OUT3 16 : VH 15 : GNDO 14 : CSCP 13 : FB3 12 : - INE3 11 : CS3 (FPT-20P-M06) MB39A112 s PIN DESCRIPTION Pin No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Symbol CS1 - INE1 FB1 VCC RT CT GND FB2 - INE2 CS2 CS3 - INE3 FB3 CSCP GNDO VH OUT3 OUT2 OUT1 VCCO I/O  I O     O I   I O   O O O O  Descriptions CH1 soft-start setting capacitor connection terminal. CH1 error amplifer inverted input terminal. CH1 error amplifer output terminal. Control circuit power supply terminal. Triangular-wave oscillation frequency setting resistor connection terminal. Triangular-wave oscillation frequency setting capacitor connection terminal. Ground terminal. CH2 error amplifier output terminal. CH2 error amplifier inverted input terminal. CH2 soft-start setting capacitor connection terminal. CH3 soft-start setting capacitor connection terminal. CH3 error amplifier...