Renesas ISL9120IRN-EVZ

Overview

ISL9120IRN-EVZ from Intersil is an evaluation board for the ISL9120IRNZ fixed-output 3.3V buck-boost regulator IC, designed to demonstrate seamless mode transitions between buck, boost, and automatic bypass operation across 1.8V–5.5V input range while delivering up to 800mA output current with up to 98% efficiency. It supports rapid prototyping of low-power portable power rails in smartphones, wearables, and IoT edge nodes.

For engineers reviewing the ISL9120IRN-EVZ datasheet, ISL9120IRN-EVZ pinout, ISL9120IRN-EVZ application, or ISL9120IRN-EVZ equivalent, this board enables immediate validation of dynamic input voltage handling, forced bypass quiescent current (≤3.5µA), soft-start timing (1ms), thermal shutdown behavior (150°C), and PFM-controlled light-load efficiency - all critical for battery-powered system power architecture decisions.

Technical Context

The ISL9120IRN-EVZ implements a complete reference design for the ISL9120IRNZ IC, featuring a single 1µH shielded inductor, 10µF X5R input capacitor, and 47µF X5R output capacitor on a compact PCB layout optimized for minimal EMI and high switching efficiency. It exposes all control pins (EN, BYPS) and feedback points (VIN, VOUT, LX1, LX2, PGND, GND) for real-time probing and functional verification.

This evaluation platform validates the IC's adaptive multilevel current limit scheme (32 levels, 350mA–2A peak), automatic bypass activation within ±1–2% VIN–VOUT delta, and seamless buck-to-boost transition without output disturbance - all under programmable load conditions and variable input voltage sweeps.

Key Specifications

Availability

ISL9120IRN-EVZ is available at Aetrix Electronics and suitable for smartphone power validation, wearable device battery rail testing, and IoT sensor node energy optimization requiring stable component supply and rapid design iteration.

Supply support for ISL9120IRN-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

Intersil Corporation is a leading provider of precision analog and power management solutions, acquired by Renesas Electronics in 2017. Its products serve industrial, infrastructure, mobile computing, and high-end consumer markets.

The ISL9120IRN-EVZ belongs to Intersil's compact DC/DC regulator product line, engineered specifically for space-constrained, battery-powered applications demanding ultra-low quiescent current, wide input voltage tolerance, and seamless buck-boost-bypass operation without external mode control logic.

FAQ

What is the primary purpose of the ISL9120IRN-EVZ evaluation board?

The ISL9120IRN-EVZ evaluation board is a fully assembled, tested reference platform for the ISL9120IRNZ 3.3V fixed-output buck-boost regulator IC. It enables engineers to validate key performance metrics-including automatic buck/boost/bypass transitions, efficiency across 1.8V–5.5V input, 800mA load capability, and <3.5µA forced bypass current-without designing custom hardware. The ISL9120IRN-EVZ includes all recommended passive components per the datasheet and exposes test points for real-time measurement of VIN, VOUT, LX1, LX2, EN, and BYPS signals.

Does the ISL9120IRN-EVZ support adjustable output voltages?

No, the ISL9120IRN-EVZ is configured exclusively for the ISL9120IRNZ variant, which provides a factory-trimmed fixed 3.3V output. It connects VOUT directly to FB per Figure 18 of the datasheet and does not include an external resistor divider network. To evaluate adjustable output operation, users must refer to the ISL9120IRA-EVZ board, which supports the ISL9120IRAZ adjustable version with R1/R2 programming and feed-forward capacitor C4.

How is the ISL9120IRN-EVZ powered and what are its input requirements?

The ISL9120IRN-EVZ accepts a DC input voltage from 1.8V to 5.5V applied to the VIN terminal, matching the full operating range of the underlying ISL9120IRNZ IC. It includes a 10µF X5R ceramic input capacitor rated for 10V and optimized for low ESL/ESR. Input undervoltage lockout activates below 1.725V (rising threshold), ensuring reliable startup only when sufficient supply headroom exists. The ISL9120IRN-EVZ does not include onboard voltage conversion or regulation for its own bias-it relies entirely on the external input source.

Can the ISL9120IRN-EVZ demonstrate forced bypass mode, and how is it activated?

Yes, the ISL9120IRN-EVZ fully supports forced bypass mode via the BYPS pin. Driving BYPS HIGH (≥1.4V) engages direct VIN-to-VOUT conduction through internal MOSFETs and the external inductor, reducing quiescent current to ≤3.5µA. This mode is intended for scenarios where regulation is unnecessary-such as powering an LDO in standby-and requires ≥800µs minimum assertion time. The ISL9120IRN-EVZ provides dedicated test points and jumper options to monitor bypass behavior, including voltage drop and transient response during mode entry/exit.

What protection features of the ISL9120IRNZ IC are verified on the ISL9120IRN-EVZ board?

The ISL9120IRN-EVZ validates four core protection mechanisms of the ISL9120IRNZ IC: (1) Undervoltage lockout (UVLO) with 1.725V rising threshold; (2) Thermal shutdown at 150°C (with 35°C hysteresis and automatic soft-start recovery); (3) Soft-discharge via 110Ω internal resistor when EN is pulled LOW; and (4) Overcurrent limiting via adaptive 32-level peak current control (350mA–2A). All protections operate autonomously without firmware or external supervision, and the ISL9120IRN-EVZ layout preserves signal integrity for accurate fault detection and response timing measurement.