Renesas ISL91133IIM-EVZ

Overview

ISL91133IIM-EVZ from Renesas Electronics is an evaluation board for the ISL91133IIMZ high-efficiency 2.3A boost regulator with input-to-output bypass functionality. It supports fixed 3.3V/3.5V output variants, operates from 2.35V–5.4V input, delivers up to 2.3A at 3.3V, and features 2.5MHz switching frequency and 38mΩ bypass MOSFET for ultra-low dropout in battery-powered mobile applications.

For engineers reviewing the ISL91133IIM-EVZ datasheet, ISL91133IIM-EVZ pinout, ISL91133IIM-EVZ application, or ISL91133IIM-EVZ equivalent, this evaluation platform enables rapid validation of boost-to-bypass transition behavior, light-load PFM efficiency, thermal performance under 2.3A load, and VSEL-controlled dual-output voltage selection in real-world smartphone and RF power amplifier supply designs.

Technical Context

The ISL91133IIM-EVZ implements a complete reference design for the ISL91133IIMZ IC, featuring a 0.47µH shielded inductor, dual 22µF X5R ceramic output capacitors, and layout-optimized 16-ball WLCSP footprint matching the 1.78mm×1.78mm package. It validates the device's valley-current-mode PWM control, auto/forced bypass mode switching (with 100mV hysteresis), and soft-start sequencing using ILIN1/ILIN2 linear current ramps.

This board demonstrates critical system-level behaviors: PG open-drain power-good assertion timing, BYPS pin-controlled forced bypass entry with internal discharge circuit activation when VOUT > VIN, and load transient response (10mA ↔ 1500mA) with <200mV droop under 3.3V output regulation - all verified per FN8680 Rev 1.00 test conditions.

Key Specifications

Availability

ISL91133IIM-EVZ is available at Aetrix Electronics and suitable for smartphone power architecture validation, USB OTG source design, 4G RF PA biasing, and portable medical device supply testing requiring stable component supply and fast-turn evaluation support.

Supply support for ISL91133IIM-EVZ 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

Renesas Electronics is a global semiconductor leader delivering microcontrollers, analog, power, and SoC solutions for automotive, industrial, infrastructure, and IoT applications.

The ISL91133 product line is designed specifically for high-efficiency, space-constrained battery-powered systems requiring seamless transition between boost regulation and low-dropout bypass operation - targeting smartphones, tablets, and wireless communication devices.

FAQ

What is the primary function of the ISL91133IIM-EVZ evaluation board?

The ISL91133IIM-EVZ evaluation board is a fully assembled and tested platform for validating the ISL91133IIMZ 2.3A boost regulator with bypass capability. It enables engineers to characterize efficiency across load and input voltage ranges, verify auto/forced bypass mode transitions, assess thermal performance under 2.3A load, and evaluate VSEL-controlled dual-output voltage selection - all using the exact 16-ball WLCSP footprint and component values specified in the FN8680 datasheet for the ISL91133IIMZ.

Does the ISL91133IIM-EVZ support both auto and forced bypass modes?

Yes, the ISL91133IIM-EVZ fully supports both auto and forced bypass modes as implemented by the ISL91133IIMZ IC. Auto bypass activates when the BYPS pin is pulled HIGH and VIN exceeds VOUT by 1.5% for 5µs without switching activity; forced bypass engages immediately when BYPS is pulled LOW. The board includes accessible BYPS and VSEL pins, allowing real-time mode control and observation of the 38mΩ bypass FET's behavior, including internal discharge sequencing when VOUT > VIN.

What output voltage options does the ISL91133IIM-EVZ validate?

The ISL91133IIM-EVZ validates the ISL91133IIMZ's fixed 3.3V/3.5V dual-output configuration. The VSEL pin allows selection between these two levels during boost operation: pulling VSEL HIGH selects 3.5V output, while pulling it LOW selects 3.3V. This enables compensation for load transient droop and supports dynamic voltage scaling in applications like RF power amplifiers where precise bias voltage tuning is required.

How is thermal performance evaluated on the ISL91133IIM-EVZ board?

The ISL91133IIM-EVZ board incorporates thermal design features aligned with the ISL91133IIMZ's 14°C/W θ_JB specification, including optimized copper pour on PGND layers and direct thermal vias beneath the WLCSP package. Engineers can monitor thermal warning (120°C) and shutdown (150°C) thresholds via the PG pin status and correlate temperature rise with 2.3A continuous load using standard IR imaging or thermocouple measurement - consistent with the thermal test conditions defined in FN8680 Rev 1.00.

Can the ISL91133IIM-EVZ be used to test load transient response?

Yes, the ISL91133IIM-EVZ is configured to accurately measure load transient response per Figure 11 and Figure 12 of FN8680 Rev 1.00. With its 2×22µF X5R output capacitors and low-ESR layout, it demonstrates <200mV output droop during 10mA ↔ 1500mA step changes at 3.3V output, and validates the device's ability to recover within 100µs. Test points for VOUT, LX, and PG allow oscilloscope-based analysis of regulation stability, bypass mode entry timing, and fault flag assertion during overcurrent events.