Renesas ISL85003EVAL2Z

Overview

ISL85003EVAL2Z from Renesas Electronics is an evaluation board designed to demonstrate the performance of the ISL85003 and ISL85003A 3A synchronous buck regulators in point-of-load applications. It supports 4.5V–18V input, delivers up to 3A at resistor-programmable output voltages (e.g., 5V ±1%), and features current-mode control with DCM/CCM operation, 500kHz fixed switching frequency, and external synchronization capability up to 2MHz.

For engineers reviewing the ISL85003EVAL2Z datasheet, ISL85003EVAL2Z pinout, ISL85003EVAL2Z application, or ISL85003EVAL2Z equivalent, this board enables rapid validation of regulator loop stability, efficiency under light/heavy load, soft-start behavior (on ISL85003A), and thermal performance using internal or external compensation - all with switch-selectable EN and MODE controls.

Technical Context

The ISL85003EVAL2Z implements a complete reference design for the ISL85003FRZ and ISL85003AFRZ buck regulators in a 4×3mm DFN-12 package. It integrates key support components including a 4.7µH power inductor (RLF7030T-4R7M3R4), 150µF bulk output capacitor (EEE-FK1H151P), dual 10µF input capacitors, and precision feedback resistors (R1 = 301kΩ, R2 = 57.6kΩ for 5V output).

Board-level functionality includes jumper-selectable PWM/DCM mode (SW2), enable/disable control (SW1), test points for VIN, VOUT, PG, SYNC, and COMP, plus scope probe connectors (131-4353-00) for real-time waveform capture of switching node, feedback, and gate drive signals.

Key Specifications

Availability

ISL85003EVAL2Z is available at Aetrix Electronics and suitable for point-of-load DC/DC converter development, power supply validation, and embedded system power architecture prototyping requiring stable component supply and fast time-to-test.

Supply support for ISL85003EVAL2Z 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, and IoT applications, with deep expertise in high-efficiency power management ICs.

The ISL85003EVAL2Z belongs to Renesas' ISL85003 product line - a family of low-quiescent-current, high-efficiency synchronous buck regulators targeting space-constrained, thermally sensitive point-of-load applications in networking, computing, and industrial equipment.

FAQ

What is the primary function of the ISL85003EVAL2Z?

The ISL85003EVAL2Z is an evaluation board used to characterize and validate the electrical performance of the ISL85003FRZ and ISL85003AFRZ 3A synchronous buck regulators. It provides a fully assembled, tested reference design with accessible test points, switch-selectable operating modes, and preconfigured 5V output - enabling engineers to verify efficiency, transient response, thermal behavior, and loop stability without custom PCB development. The ISL85003EVAL2Z directly supports design-in of the underlying ISL85003 devices.

Which regulator ICs does the ISL85003EVAL2Z support?

The ISL85003EVAL2Z is explicitly designed for the ISL85003FRZ and ISL85003AFRZ buck regulators, both housed in a 4×3mm DFN-12 package. The board's schematic (Rev B), BOM, and user guide confirm U1 is populated with either ISL85003FRZ or ISL85003AFRZ. It does not support other ISL85xxx variants or unrelated buck controllers. The ISL85003EVAL2Z provides identical hardware compatibility for both parts, differing only in firmware-level features like adjustable soft-start (ISL85003A only).

How do I configure the ISL85003EVAL2Z for a non-5V output voltage?

To configure the ISL85003EVAL2Z for a different output voltage, replace resistor R2 (57.6kΩ for 5V) with a value calculated using Equation 1: R2 = R1 × (VOUT − 0.8V) / 0.8V, where R1 remains 301kΩ. For example, 3.3V requires R2 ≈ 96.3kΩ. Component selection tables in AN1930 list recommended inductors (e.g., 4.7µH), output capacitors (C5/C6 = 47µF), and optional C4 (4.7pF) for compensation tuning. The ISL85003EVAL2Z supports outputs from 0.8V to 5V using this method.

What are the key jumpers and switches on the ISL85003EVAL2Z?

The ISL85003EVAL2Z features two SPDT toggle switches: SW1 controls EN (ON = enabled, OFF = disabled VOUT), and SW2 selects MODE (PWM = forced continuous conduction, DCM = automatic discontinuous mode at light load). No jumpers are required for basic operation - all critical connections (VIN, VOUT, PGND) use terminal posts (P4–P9), and test points (J1/J2) provide direct access to PHASE and VOUT for oscilloscope probing. The ISL85003EVAL2Z uses GT11MSCBE switches for reliable manual control during lab testing.

Does the ISL85003EVAL2Z support external synchronization?

Yes, the ISL85003EVAL2Z supports external clock synchronization up to 2MHz via the SYNC pin (U1 Pin 13), as specified for the ISL85003FRZ. A signal generator can drive this pin through P2 (labeled "SYNC" on the board). This feature allows EMI reduction through frequency dithering or alignment with system clocks. Note that the ISL85003AFRZ variant does not support SYNC; thus, external synchronization is only functional when the ISL85003FRZ is installed on the ISL85003EVAL2Z.