Renesas ISL8115DEMO1Z

Overview

The ISL8115DEMO1Z from Renesas Electronics is a compact, fully assembled demonstration board implementing the ISL8115 synchronous buck PWM controller for 5V/10A DC-DC conversion. It operates across a 16V–36V input range, delivers 90.12% efficiency at 24V/10A, and features voltage-mode control with input feed-forward for stable loop gain and fast transient response in wide-input industrial power systems.

For engineers reviewing the ISL8115DEMO1Z datasheet, ISL8115DEMO1Z test setup, ISL8115DEMO1Z schematic, or ISL8115DEMO1Z BOM, this evaluation board provides validated reference design data-including measured line/load regulation, startup/shutdown waveforms, OVP/UVP/OCP/OTP protection thresholds, and layout guidance-for rapid integration of high-efficiency 5V point-of-load supplies.

Technical Context

The ISL8115DEMO1Z implements a fixed-output 5V synchronous buck converter using the ISL8115 controller IC, which employs voltage-mode PWM with leading-edge modulation and nonlinear control to maintain constant loop gain across its 16V–36V input range. Its integrated 5V/4A gate drivers drive dual N-channel MOSFETs (BSC039N06NS) in a single-phase topology with 2.4µH inductance and 4×100µF output capacitance.

It supports programmable switching frequency from 150kHz to 1.5MHz (default 600kHz), external clock synchronization, diode emulation mode for light-load efficiency, and prebias start-up. Protection includes adjustable overcurrent (13A peak), input UVP (14.2V falling / 15V rising), output OVP/UVP, and thermal shutdown.

Key Specifications

Availability

The ISL8115DEMO1Z is available at Aetrix Electronics and suitable for industrial power supply validation, embedded system PoL testing, and automotive auxiliary rail prototyping requiring stable component supply and production-ready reference design fidelity.

Supply support for ISL8115DEMO1Z 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 manufacturer specializing in microcontrollers, analog power, and mixed-signal solutions for industrial, automotive, and infrastructure markets.

The ISL8115DEMO1Z belongs to Renesas' high-performance analog power evaluation platform family, designed to accelerate adoption of wide-input synchronous buck controllers in rugged, space-constrained power systems.

FAQ

What is the primary function of the ISL8115DEMO1Z?

The ISL8115DEMO1Z is a fully assembled demonstration board that implements the ISL8115 synchronous buck PWM controller to deliver a regulated 5V/10A output from a 16V–36V input. It serves as a hardware reference design-complete with schematic, layout, BOM, and performance waveforms-to validate system-level integration, efficiency, transient response, and protection behavior before custom PCB development. The ISL8115DEMO1Z enables rapid evaluation without component selection or layout risk.

Does the ISL8115DEMO1Z support adjustable output voltage?

Yes, the ISL8115DEMO1Z supports output voltage adjustment via resistor divider R4/R1 on the feedback (FB) pin. The default 5V output is set using R4 = 2kΩ and R1 = 14.7kΩ, referencing the ISL8115's internal 0.6V precision bandgap. Equation 1 in the AN1919 manual provides the exact calculation: VOUT = 0.6V × (1 + R1/R4). Maintaining the same R11/R8 ratio as R1/R4 preserves UVP/OVP thresholds when modifying VOUT. The ISL8115DEMO1Z documentation confirms this configurability.

Can the ISL8115DEMO1Z be synchronized to an external clock?

Yes, the ISL8115DEMO1Z supports external clock synchronization via the FSET pin. Applying a 150kHz–1.5MHz square wave (10%–90% duty cycle) to FSET locks the internal oscillator to the external signal. To enable synchronization, R27 (40.2kΩ) must be removed per the AN1919 user guide. This feature allows EMI reduction through frequency dithering or alignment with system clocks-critical in noise-sensitive applications. The ISL8115DEMO1Z schematic and test setup confirm this capability.

What protection features are implemented on the ISL8115DEMO1Z?

The ISL8115DEMO1Z implements comprehensive hardware-based protection: input undervoltage lockout (UVP) with 14.2V falling / 15V rising thresholds; output overvoltage (OVP) and undervoltage (UVP) monitoring via VMON; cycle-by-cycle overcurrent protection (OCP) with 13A peak threshold; and thermal shutdown (OTP). These functions are directly managed by the ISL8115 controller and verified in Figures 19–20 of the AN1919 manual. The ISL8115DEMO1Z also supports prebias start-up and soft-start to prevent inrush stress.

Is the ISL8115DEMO1Z compatible with 12V input applications?

Yes, the ISL8115DEMO1Z can be modified for 12V input operation. Table 2 in AN1919 specifies replacing R35 with 71.5kΩ to adjust input UVP thresholds, and recommends additional component changes-including compensation network tuning-for optimal stability and transient response. While the base board is optimized for 16V–36V, Renesas explicitly states it "can be modified to support multiple applications" per customer requirements. The ISL8115DEMO1Z design guide validates this adaptability.