Renesas ISL91133IIL-EVZ

Overview

ISL91133IIL-EVZ from Renesas Electronics is an evaluation board for the ISL91133IILZ high-efficiency 2.3A boost regulator with input-to-output bypass functionality. It supports fixed 3.15V/3.3V output variants, operates from 2.35V–5.4V input, delivers up to 2.3A at 3.3V output, and features 2.5MHz switching frequency and ultra-low 45μA quiescent current in Forced Bypass mode - designed for battery-powered mobile power management.

For engineers reviewing the ISL91133IIL-EVZ datasheet, ISL91133IIL-EVZ pinout, ISL91133IIL-EVZ application, or ISL91133IIL-EVZ equivalent, this board enables rapid validation of boost-to-bypass transition behavior, load transient response under USB OTG and RF PA supply conditions, and efficiency optimization across VIN = 2.5V–4.2V with 0.47µH inductor and dual 22µF ceramic output capacitors.

Technical Context

The ISL91133IIL-EVZ implements a complete reference design for the ISL91133IILZ IC, featuring a 16-ball 1.78mm×1.78mm WLCSP packaged regulator with integrated synchronous N- and P-channel MOSFETs (Q1/Q2), a 38mΩ bypass FET (Q3), valley-current-mode PWM control, and auto/forced bypass logic. It validates critical timing behaviors including 600µs soft-start time, 20ms fault reset timer, and <5µs auto-bypass entry latency when VIN exceeds VOUT by 1.5%.

This evaluation platform supports all functional modes of the ISL91133IILZ: Boost (2.5MHz PWM, 4A peak current limit), PFM light-load operation, and both Forced Bypass (BYPS = LOW) and Auto Bypass (BYPS = HIGH) with 100mV hysteresis - enabling direct measurement of bypass R_DS(ON) (38mΩ), dropout voltage (≤150mV at 600mA), and PG assertion timing relative to VOUT regulation.

Key Specifications

Availability

ISL91133IIL-EVZ is available at Aetrix Electronics and suitable for smartphone power architecture validation, tablet PC USB OTG source qualification, and 4G RF power amplifier supply testing requiring stable component supply and fast-turn evaluation support.

Supply support for ISL91133IIL-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 management, and timing solutions for automotive, industrial, and consumer applications.

The ISL91133 product line was engineered specifically for single-cell Li-ion/Li-polymer battery systems needing high-efficiency boost conversion with seamless transition to low-dropout bypass operation - targeting space-constrained mobile and wireless infrastructure designs.

FAQ

What is the primary function of the ISL91133IIL-EVZ evaluation board?

The ISL91133IIL-EVZ evaluation board is a fully assembled and tested platform for validating the ISL91133IILZ 2.3A boost regulator with bypass capability. It enables engineers to characterize efficiency, load transient response, bypass mode timing, and power-good signaling under real-world conditions using the exact 16-ball WLCSP package and recommended 0.47µH inductor + dual 22µF output capacitor layout specified in the ISL91133IILZ datasheet.

Does the ISL91133IIL-EVZ support both auto and forced bypass modes?

Yes, the ISL91133IIL-EVZ supports both modes via dedicated test points: pulling the BYPS pin LOW activates Forced Bypass (disabling boost circuitry and turning on Q3), while pulling BYPS HIGH enables Auto Bypass (triggered when VIN exceeds VOUT by 1.5% for 5µs with no switching activity). The board includes jumpers and signal access points to monitor LX, PG, and VOUT during mode transitions.

What output voltage options does the ISL91133IIL-EVZ validate?

The ISL91133IIL-EVZ is configured for the ISL91133IILZ variant, which provides dual fixed outputs: 3.15V (VSEL = LOW) and 3.3V (VSEL = HIGH). The board includes a VSEL test point and pull-up/pull-down resistors to verify output voltage scaling and transient droop compensation - matching the 3.15V/3.3V selection logic defined in the ISL91133IILZ datasheet.

Can the ISL91133IIL-EVZ be used to measure thermal performance?

Yes, the ISL91133IIL-EVZ includes thermal vias and copper pour optimized per Renesas' WLCSP layout guidelines, enabling accurate junction temperature estimation. It supports direct measurement of thermal warning (120°C) and shutdown (150°C) thresholds using the PG flag and external thermocouple placement near the IC die location - consistent with the θ_JA = 70°C/W and θ_JB = 14°C/W thermal resistance values specified for the 16-ball WLCSP package.

What external components are pre-installed on the ISL91133IIL-EVZ board?

ISL91133IIL-EVZ ships with all key external components installed: a 0.47µH shielded inductor (TDK TFM201610A), input capacitor (22µF X5R), dual output capacitors (2×22µF X5R), and precision feedback resistors matching the ISL91133IILZ 3.15V/3.3V output configuration. Test points provide access to VIN, VOUT, LX, PG, EN, BYPS, and VSEL for oscilloscope and load-step measurements.