Radiation Tolerant Single/Dual-Phase Current Mode PWM Controller

The ISL73847M is a synchronous buck controller that can operate as a single or dual-phase controller. It works with the ISL71441M (half-bridge GaN FET driver) to generate point-of-load voltage rails for commercial space applications.

It accepts an input voltage range of 4.5V to 19V with a programmable PWM output switching frequency between 250kHz and 1.5MHz with a single resistor. The output can regulate a voltage upwards of 600mV and is limited on the top end by the minimum off time and selected switching frequency.

The ISL73847M features built-in current sharing, enabling two-phase operation within a single device and four-phase operation using two ISL73847M devices, all without requiring an external clock at ≤ 1.04MHz. For multiphase operation at other frequencies, the ISL74420 provides additional scalability, making it a flexible solution for multiphase power architectures.

Its wide input voltage range makes it ideal for high-current FPGA core power and general-purpose power applications. The current mode modulation architecture simplifies loop compensation, enhances power supply rejection, and supports remote sensing to compensate for voltage drops under load. These features deliver a high-density, robust power solution that minimizes external components while ensuring efficient and reliable performance.