5V or +12V Single-Phase Synchronous Buck Converter PWM Controller with Integrated MOSFET Gate Drivers

The ISL8105, ISL8105A is a simple single-phase PWM controller for a synchronous buck converter. It operates from +5V or +12V bias supply voltage. With integrated linear regulator, boot diode, and N-Channel MOSFET gate drivers, the ISL8105, ISL8105A reduces external component count and board space requirements. These make the IC suitable for a wide range of applications. Utilizing voltage-mode control, the output voltage can be precisely regulated to as low as 0. 6V. The 0. 6V internal reference features a maximum tolerance of ±1. 0% over the commercial temperature range, and ±1. 5% over the industrial temperature range. Two fixed oscillator frequency versions are available; 300kHz (ISL8105 for high efficiency applications) and 600kHz (ISL8105A for fast transient applications). The ISL8105, ISL8105A features the capability of safe start-up with pre-biased load. It also provides overcurrent protection by monitoring the ON-resistance of the bottom-side MOSFET to inhibit PWM operation appropriately. During start-up interval, the resistor connected to BGATE/BSOC pin is employed to program overcurrent protection condition. This approach simplifies the implementation and does not deteriorate converter efficiency.