Renesas ISL8101CRZ

Overview

ISL8101CRZ from Intersil is a two-phase multiphase buck PWM controller with integrated MOSFET drivers, designed for precision voltage regulation in high-current microprocessor power supplies up to 80A. It supports Intel VRM9/VRM10 and AMD Hammer VID codes, delivers ±1% system accuracy over temperature, operates from 5V–12V input, and features r_DS(ON)-based current sensing for channel balancing.

For engineers reviewing the ISL8101CRZ datasheet, ISL8101CRZ pinout, ISL8101CRZ application, or ISL8101CRZ equivalent, this controller enables fast transient recovery, pre-biased start-up, lossless current sampling, and multi-tiered overvoltage protection in space-constrained server and embedded CPU power designs.

Technical Context

The ISL8101CRZ implements voltage-mode control with independent PWM comparators per phase, driven by out-of-phase sawtooth waveforms at 189–255 kHz. Its current balance loop samples lower MOSFET r_DS(ON) voltage during conduction, time-multiplexing signals across ISEN to generate a shared reference for per-channel duty-cycle correction.

Overvoltage protection includes dual thresholds: 1.65V/1.95V (disabled state) and VID + 200 mV (active state), with 100 mV hysteresis. The controller disables upper/lower gates on overcurrent detection and enters hiccup mode-4096-cycle wait followed by soft-start-with recovery attempted until fault removal.

Key Specifications

Pinout & Package

ISL8101CRZ is housed in a 24-lead, 4 mm × 4 mm, 0.5 mm pitch QFN package (JEDEC MO-220, pkg drawing L24.4x4B) with exposed thermal pad. The RoHS-compliant, Pb-free construction uses 100% matte tin e3 termination and is rated MSL3.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multiphase buck controller applications.

Compared with ISL6322IRZ and TPS53679RSLR, the ISL8101CRZ provides the most direct analog VID implementation for VRM9/VRM10/Hammer CPUs in two-phase configurations, with minimal BOM count, no digital interface overhead, and proven field reliability in enterprise computing power supplies.

Availability

ISL8101CRZ is available at Aetrix Electronics and suitable for server CPU core power, workstation GPU VRMs, embedded AI accelerator supplies, and industrial FPGA core rails requiring stable component supply and long-lifecycle support.

Supply support for ISL8101CRZ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Intersil (now part of Renesas Electronics) is a semiconductor company specializing in high-performance analog and power management ICs for computing, communications, and industrial markets.

The ISL8101CRZ belongs to Intersil's multiphase buck controller product line, engineered specifically for high-current, low-voltage CPU and GPU core power delivery with emphasis on VID compatibility, accuracy, and thermal efficiency.

FAQ

What is the operating temperature range for the ISL8101CRZ?

The ISL8101CRZ is specified for commercial temperature operation from 0°C to +70°C. Its thermal resistance (θ_JA = 45°C/W) and junction temperature limit of +150°C allow reliable operation in typical server and workstation VRM layouts without forced cooling. The device does not support industrial-grade -40°C to +85°C operation - that variant is the ISL8101IRZ.

Does the ISL8101CRZ support load-line (droop) regulation?

No, the ISL8101CRZ does not intrinsically support load-line regulation. As explicitly stated in the datasheet, "the ISL8101, though, does not intrinsically allow for load-line regulation (no droop)." Output voltage remains fixed per VID code regardless of load current, making it suitable for applications where constant-voltage regulation is required rather than adaptive voltage positioning.

How does the ISL8101CRZ implement overcurrent protection?

The ISL8101CRZ monitors channel current via r_DS(ON) sensing on the lower MOSFETs, time-multiplexing the sampled voltages across the ISEN pin. An internal comparator triggers overcurrent protection if both channels exceed 95 µA at the ISEN node simultaneously, or if either channel exceeds that threshold for seven consecutive switching cycles. Upon detection, both upper and lower gates are disabled and the controller enters hiccup mode.

Can the ISL8101CRZ start up into a pre-biased output?

Yes, the ISL8101CRZ supports pre-biased output start-up. This feature allows the controller to safely initiate regulation when the output rail already holds a voltage - for example, during hot-swap or multi-rail sequencing scenarios. The architecture prevents reverse current flow through the low-side MOSFETs and avoids output collapse during initial soft-start ramp.

What package type and lead finish does the ISL8101CRZ use?

The ISL8101CRZ uses a 24-lead, 4 mm × 4 mm QFN package (JEDEC MO-220, drawing L24.4x4B) with an exposed thermal pad. It features a Pb-free, RoHS-compliant construction with 100% matte tin (e3) termination, qualified for both SnPb and Pb-free reflow processes per IPC/JEDEC J-STD-020.