Renesas ISL8500EVAL2Z

Overview

ISL8500EVAL2Z from Renesas Electronics is an evaluation board designed to demonstrate the ISL8500 2A negative-output buck-boost DC/DC regulator in a 4mm × 3mm 12-lead DFN package. It supports 9V–14V input and delivers adjustable -0.6V to -12.6V output at up to 2A continuous current, operating at a fixed 500kHz switching frequency with PGOOD, soft-start, and thermal/overcurrent protection.

For engineers reviewing the ISL8500EVAL2Z datasheet, ISL8500EVAL2Z setup procedure, ISL8500EVAL2Z test equipment requirements, or ISL8500EVAL2Z schematic validation, this kit provides a production-ready reference for point-of-load negative voltage generation in handheld instruments and general-purpose embedded systems requiring stable -12V rails from 12V inputs.

Technical Context

The ISL8500EVAL2Z implements a non-synchronous buck-boost topology optimized for 12V input to -12V output conversion, using the ISL8500IRZ controller with integrated high-side MOSFET and boot diode. Its fixed 500kHz PWM operation enables compact external components - including a 22µH Vishay IHLP2525CZRZ inductor and 47µF TDK C3225X5R1C476M output capacitor - minimizing PCB area to under 0.385in².

Control features include voltage-mode regulation with feed-forward, externally adjustable soft-start via R2/C2 network, output undervoltage lockout, and internal 5V LDO. Protection functions are implemented through cycle-by-cycle overcurrent detection, thermal shutdown, and PGOOD monitoring tied to FB and COMP pins.

Key Specifications

Availability

ISL8500EVAL2Z is available at Aetrix Electronics and suitable for point-of-load power design, handheld instrument development, and general-purpose negative voltage generation requiring stable component supply and rapid prototyping capability.

Supply support for ISL8500EVAL2Z 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 Corporation is a global semiconductor leader delivering microcontrollers, analog, power, and SoC solutions for automotive, industrial, and enterprise applications.

The ISL8500EVAL2Z belongs to Renesas' precision DC/DC evaluation platform family, engineered to accelerate adoption of high-efficiency buck-boost regulators in space-constrained, low-noise embedded systems.

FAQ

What is the primary function of the ISL8500EVAL2Z evaluation board?

The ISL8500EVAL2Z evaluation board demonstrates the performance of the ISL8500 2A buck-boost regulator, specifically configured to generate a stable negative output voltage (e.g., -12V) from a positive 9V–14V input. It includes all necessary passive components, test points, and layout optimizations to validate efficiency, transient response, and protection behavior per AN1500 Rev 0.00.

Which IC does the ISL8500EVAL2Z board feature, and what package is used?

The ISL8500EVAL2Z board integrates the ISL8500IRZ - a 2A buck-boost DC/DC regulator in a 4mm × 3mm 12-lead DFN package with 1mm max height. This controller includes an integrated high-side MOSFET, boot diode, internal 5V LDO, and voltage-mode control architecture, as confirmed in the Bill of Materials and schematic on page 3 of AN1500.

Can the output voltage of the ISL8500EVAL2Z be adjusted, and how is it done?

Yes, the ISL8500EVAL2Z output voltage is adjustable from -0.6V to -12.6V using an external resistor divider network connected to the FB pin. Equation 1 in AN1500 defines VOUT = -0.6V × (1 + R2/R1); default -12V operation uses R1 = 5.11kΩ and R2 = 20kΩ. The board includes populated R1 and R2, with optional R30 for VIN < 6V operation.

What test equipment is required to evaluate the ISL8500EVAL2Z according to the user manual?

Per AN1500 Section "Recommended Equipment", evaluating the ISL8500EVAL2Z requires: a 0–15V/5A power supply (e.g., notebook AC adapter), an electronic load capable of sinking up to 5A, two digital multimeters, a 100MHz quad-trace oscilloscope, and a signal generator. Test points TP1–TP4 and scope probe pads SP1/SP2 support direct probing of VIN, VOUT, EN, and PG signals.

Does the ISL8500EVAL2Z include protection features, and how are they verified?

Yes, the ISL8500EVAL2Z implements overcurrent protection, thermal overload shutdown, output undervoltage lockout, and PGOOD monitoring - all inherent to the ISL8500IRZ controller. These are verified in AN1500's Typical Performance Curves: Figure 26 shows output short-circuit behavior, Figure 27 confirms recovery, and Figure 22 validates load transient stability under 0A→1A steps.