TC120 Datasheet | Microchip Technology

Features - Internal Switching Transistor Supports 600m A Output Current - External Switching Transistor Control for Output Currents of 2A+ - 300k Hz Oscillator Frequency Supports Small Inductor Size - Short Circuit Protection - Built-In Undervoltage Lockout - 95% Typical Efficiency - Automatic Switchover to Current-Saving PFM Mode at Low Output Loads - Automatic Output Capacitor Discharge While in Shutdown - Programmable Soft-Start - Power-Saving Shutdown Mode - Small 8-Pin SOP Package Package Type 8-Pin SOP VIN 1 EXTW 2 CPC 3 SHDN/SS 4 8 LX EXT GND SENSE 7 6 5 General Description TC120 is a 300k Hz PFM/PWM step-down (Buck) DC/ DC regulator/controller bination for use in systems operating from two or more cells, or in line-powered applications. It uses PWM as the primary modulation scheme, but automatically converts to PFM at low output loads for greater efficiency. It requires only an external inductor, Schottky diode, and two capacitors to implement a step-down converter having a maximum output current of 600m A (VIN = 5V, VOUT = 3.3V). An external switching transistor (P-channel MOSFET) can be added to increase output current capability to support output loads of 2A or more. The TC120 consumes only 55µA (max) of supply current (VOUT = 3.3V) and can be placed in shutdown mode by bringing the shutdown input (SHDN) low. During shutdown, the regulator is disabled, supply current is reduced to 2.5µA (max), and VOUT is internally pulled to ground, discharging the output capacitor. Normal operation resumes when SHDN is brought high. Other features include a built-in undervoltage lockout (UVLO), an externally programmable soft start time, and output short circuit protection. The TC120 operates from a maximum input voltage of 10V and is available in a low-profile 8-Pin SOP package. Applications - - - - - - Portable Test Equipment Local Logic Supplies Portable Audio Systems Portable Scanners Palmtops Electronic Organizers Device Selection Table Part Number...