The CS4124 is a monolithic integrated circuit designed primarily to control the rotor speed of permanent magnet, direct current (DC) brush motors. It drives the gate of an N channel power MOSFET or IGBT with a user–adjustable, fixed frequency, variable duty cycle, pulse width modulated (PWM) signal. The CS4124 can also be used to control other loads such as incandescent bulbs and solenoids. Inductive current from the motor or solenoid is recirculated through an external diode.

The CS4124 accepts a DC level input signal of 0 to 5.0 V to control the pulse width of the output signal. This signal can be generated by a potentiometer referenced to the on–chip 5.0 V linear regulator, or a filtered 0 to 100 PWM signal also referenced to the 5.0 V regulator.

The IC is placed in a sleep state by pulling the CTL lead below 0.5 V. In this mode everything on the chip is shutdown except for the on–chip regulator and the overall current draw is less than 275 µA. There are a number of on–chip diagnostics that look for potential failure modes and can disable the external power MOSFET.

Features

• 150 mA Peak PWM Gate Drive Output

• Patented Voltage Compensation Circuit

• 100 Duty Cycle Capability

• 5.0 V, ± 3.0 Linear Regulator

• Low Current Sleep Mode

• Overvoltage Protection

• Boost Mode Power Supply

• Output Inhibit