Radiation Hardened Single/Dual-Phase Current Mode PWM Controller

The ISL73847SLH is a synchronous buck controller that can operate as a single or dual-phase controller. It works with the ISL71441SLH (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 ISL73847SLH features built-in current sharing, enabling two-phase operation within a single device and four-phase operation using two ISL73847SLH devices, all without requiring an external clock at ≤ 1.04MHz. For multi-phase operation at other frequencies, the ISL74420 provides additional scalability, making it a flexible solution for multi-phase 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.

The ISL73847SLH also features a tri-level output that provides excellent protection against faults by driving a mid-scale voltage to signal the power stage to enter a Hi-Z condition.

The ISL73847SLH operates across the military temperature range from -55°C to +125°C and is available in a 24 Ld WSOIC plastic package.