Renesas ISL6420AEVAL3Z

Overview

ISL6420AEVAL3Z from Renesas Electronics (formerly Intersil) is an evaluation board for the ISL6420A advanced single synchronous buck PWM controller, designed to drive N-channel MOSFETs in high-efficiency DC/DC buck converters. It supports input ranges of 4.5V–5.5V and 5.5V–28V, delivers precise 0.6V reference regulation (±1.0%), enables programmable switching frequency from 100kHz to 1.4MHz, and implements lossless overcurrent protection using upper MOSFET r_DS(ON). It is used for validating power supply designs for microprocessors, DDR SDRAM termination, and networking DC/DC converters.

For engineers reviewing the ISL6420AEVAL3Z datasheet, ISL6420AEVAL3Z pinout, ISL6420AEVAL3Z application, or ISL6420AEVAL3Z equivalent, this page provides verified functional context, confirmed supply configuration options (5V vs. 5.5–28V input), validated voltage margining and external reference tracking modes, documented PGOOD delay behavior with CDEL capacitor, and real-world soft-start and hiccup-mode fault response characteristics.

Technical Context

The ISL6420AEVAL3Z implements a voltage-mode PWM control architecture with a 15MHz gain-bandwidth error amplifier and 6V/µs slew rate, enabling fast transient response in buck converter applications. It supports dual-input configurations: 5V ±10% applied to VCC5 (bypassing internal LDO) or 5.5–28V applied to VIN (activating internal 5V LDO for gate drivers and bias).

It validates the ISL6420A's key operational modes - including external reference tracking (GPIO1/REFIN = 0.6–1.25V with VMSET/MODE = H), voltage margining (±10% via VMSET resistor + GPIO1/GPIO2 logic), and diode emulation during startup for pre-biased loads - all confirmed by schematic diagrams and functional descriptions on pages 4–6 and 12–15 of FN9169 Rev 4.00.

Key Specifications

Availability

ISL6420AEVAL3Z is available at Aetrix Electronics and suitable for power supply validation, DDR termination design verification, and networking DC/DC converter prototyping requiring stable component supply and documented reference schematics.

Supply support for ISL6420AEVAL3Z 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 acquired Intersil in 2017 and maintains legacy product support, including technical documentation, errata, and long-term availability for high-reliability analog and power management ICs.

The ISL6420A - evaluated by ISL6420AEVAL3Z - belongs to Intersil's advanced PWM controller family targeting high-performance, low-voltage DC/DC conversion for microprocessor core supplies, DDR bus termination, and distributed power architectures.

FAQ

What is the primary purpose of the ISL6420AEVAL3Z evaluation board?

The ISL6420AEVAL3Z is a fully assembled demonstration and development platform for the ISL6420A synchronous buck PWM controller. It enables engineers to validate circuit performance, verify layout practices, test voltage margining and external reference tracking modes, and characterize PGOOD timing, soft-start behavior, and hiccup-mode fault recovery - all using the exact ISL6420A silicon in a production-representative configuration.

Does the ISL6420AEVAL3Z support both 5V and wide-input (5.5–28V) configurations?

Yes. The ISL6420AEVAL3Z implements the dual-input capability documented in Table 1 (page 11) of FN9169 Rev 4.00: it supports 5V ±10% applied to VCC5 (with VIN and PVCC tied to VCC5) and 5.5–28V applied to VIN (with VCC5 powered by the internal LDO). Jumper options or silkscreen markings on the board allow selection between these two operating modes.

How does the ISL6420AEVAL3Z demonstrate voltage margining functionality?

The ISL6420AEVAL3Z validates the ISL6420A's ±10% voltage margining mode using a VMSET resistor (typically 200–330kΩ) tied to ground and GPIO1/GPIO2 control lines. As described on pages 12–14, pulling GPIO2 high increases output voltage while GPIO1 high decreases it - confirmed by measurable output shifts (e.g., ±330mV on a 3.3V rail) matching Equation 3 and Figure 11 in the datasheet.

Can the ISL6420AEVAL3Z be used to evaluate external reference tracking for DDR termination supplies?

Yes. The ISL6420AEVAL3Z supports external reference tracking per page 5 and section "External Reference/DDR Supply" (page 15): when VMSET/MODE is tied high and GPIO1/REFIN is connected to a 1.25V source (e.g., DDR VDDQ/2), the board delivers a buffered REFOUT = 1.25V ±0.01V and regulates VOUT to track that reference - directly enabling VTT termination supply validation.

Is the ISL6420AEVAL3Z compatible with the ISL6420B replacement part?

No. The ISL6420AEVAL3Z is specifically designed for the ISL6420A controller and is not guaranteed to operate correctly with the ISL6420B. Although FN9169 states "NOT RECOMMENDED FOR NEW DESIGNS" and lists ISL6420B as the recommended replacement, the evaluation board's component values, layout, and firmware (if any) are optimized for ISL6420A's electrical characteristics, including its 300kHz default oscillator frequency and specific OCSET current source (100µA).