Fujitsu MB3817
The MB3817 is a pulse width modulator (PWM) type switching regulator controller IC designed for low-voltage and high-speed operation. This can be used in applications as down-conversion or down/up-conversion (Zeta method). With fewer external components and faster operating speed, the MB3817 enables reduction in power supply unit size, making it ideal for use with internal power supplies in compact, high-performance portable devices.APPLICATIONS
BIPOLAR Switching Regulator Controller MB3817 sDESCRIPTION
sFEATURES
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● Wide range of operating power supply voltages: 2.5 V to 18 V Built-in high-precision reference voltage generator: 1.5 V ± 2% High speed operation is possible: Max. 500 kHz Wide input voltage range of error amplifier: 0 to VCC – 0.9 V Built-in soft start function Built-in timer/latch-actuated short-circuiting protection circuit Totem-pole type output with adjustable on/off current (for PNP transistors) Built-in standby function Small package: SSOP-16P (FPT-16P-M05) s PACKAGE 16-pin Plastic SSOP (FPT-16P-M05) MB3817 s PIN ASSIGNMENT (TOP VIEW) CT 1 16 VREF RT +IN −IN 2 15 CTL 3 14 CSCP 4 13 CS FB 5 12 GND DTC 6 11 VE CB1 7 10 OUT CB2 8 9 V CC (FPT-16P-M05) 2 MB3817 s PIN
DESCRIPTION
Pin no. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Pin name CT RT +IN –IN FB DTC CB1 CB2 VCC OUT VE GND CS CSCP CTL VREF I/O — — I I O I — — — O — — — — I O Descriptions This pin connects to a capacitor for setting the triangular-wave frequency.