Renesas ISL85005EVAL1Z

Overview

ISL85005EVAL1Z from Renesas Electronics is an evaluation board for the ISL85005 4.5V–18V input, 5A synchronous buck regulator IC. It implements a monolithic buck converter with integrated 5A/18V high-side and low-side MOSFETs, fixed 500kHz switching frequency, current-mode control, and Diode Emulation Mode (DEM) or Forced CCM operation. Designed for rapid validation of point-of-load power delivery in embedded computing and battery-powered systems.

For engineers reviewing the ISL85005EVAL1Z datasheet, ISL85005EVAL1Z pinout, ISL85005EVAL1Z application, or ISL85005EVAL1Z equivalent, this board enables functional verification of output regulation accuracy (±1% at 0.8V reference), efficiency across load range (up to 95% at 5A), soft-start behavior (2.3ms fixed), and protection features including UVLO, OVP, cycle-by-cycle current limit, and thermal shutdown.

Technical Context

The ISL85005EVAL1Z implements the full reference design for the ISL85005 IC per Figure 1 and Figure 4 of FN8871 Rev.2.00, featuring internal compensation, 3.3µH output inductor, 10µF + 47µF output capacitance, and resistor divider for adjustable V_OUT. It supports both DEM and FCCM via SYNC/MODE pin configuration and includes all critical decoupling: 1µF on VDD, 0.1µF BOOT-to-PHASE, and ceramic input capacitor near VIN pins.

Board-level layout follows Renesas' recommended practices: dedicated AGND/PGND plane separation with single-point connection, thermal vias under EPAD, short high-current PHASE trace, and Kelvin-sense FB routing. The PG open-drain indicator and EN control interface are brought out to test points for system integration validation.

Key Specifications

Availability

ISL85005EVAL1Z is available at Aetrix Electronics and suitable for embedded computing, network equipment, and battery-powered system development requiring stable component supply and fast power architecture validation.

Supply support for ISL85005EVAL1Z 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, infrastructure, and IoT applications.

The ISL85005EVAL1Z belongs to Renesas' Power Management evaluation platform family, designed to accelerate adoption of high-efficiency, integrated DC/DC regulators in space-constrained and thermally demanding applications.

FAQ

What is the primary function of the ISL85005EVAL1Z?

The ISL85005EVAL1Z is a fully assembled evaluation board for the ISL85005 synchronous buck regulator IC. It provides a ready-to-use platform to validate input voltage range (4.5–18V), 5A output capability, 500kHz switching performance, Diode Emulation Mode (DEM), and comprehensive protection features-including UVLO, OVP, and thermal shutdown-without requiring custom PCB design. The ISL85005EVAL1Z includes all necessary passives, layout-optimized thermal design, and accessible test points for real-time measurement of V_OUT, PG, EN, and PHASE waveforms.

Does the ISL85005EVAL1Z support both DEM and Forced CCM modes?

Yes, the ISL85005EVAL1Z supports both Diode Emulation Mode (DEM) and Forced Continuous Conduction Mode (FCCM) via the SYNC/MODE pin. Pulling SYNC/MODE to AGND enables DEM for high light-load efficiency; connecting it to VDD selects FCCM for constant-frequency operation. This dual-mode capability is implemented per the ISL85005's pinout and is verified in the board's schematic (Figure 4 of FN8871). The ISL85005EVAL1Z includes jumpers or solder options to configure this mode without hardware modification.

What output voltage range can be configured using the ISL85005EVAL1Z?

The ISL85005EVAL1Z supports output voltages from 0.8V up to near the input rail (minus conduction losses), using the onboard resistor divider network connected to the FB pin. The default configuration delivers 5V from 12V input, but R1/R2 values can be changed to set 1.2V, 1.8V, 2.5V, or 3.3V per Table 2 in FN8871. The ISL85005EVAL1Z maintains ±1% regulation accuracy across temperature (−40°C to +125°C) due to the ISL85005's 0.800V ±1% internal reference and current-mode control loop stability.

How does the ISL85005EVAL1Z handle thermal management?

The ISL85005EVAL1Z uses the ISL85005's 12-pin 3mm×4mm DFN package with exposed thermal pad (EPAD), mounted directly to a copper pour connected via ≥6 thermal vias to inner ground planes. This achieves θ_JA = 41°C/W as specified in FN8871. The board layout isolates AGND and PGND with a single-point connection, minimizes high-current loop area, and places input/output capacitors adjacent to the IC-ensuring stable thermal performance at full 5A load and junction temperatures up to +125°C. The ISL85005EVAL1Z also incorporates thermal shutdown activation at 165°C with 10°C hysteresis.

Can the ISL85005EVAL1Z be synchronized to an external clock?

Yes, the ISL85005EVAL1Z supports external clock synchronization via the SYNC/MODE pin, compatible with input frequencies from 300kHz to 2MHz. The board routes this pin to a test point and includes series resistance to ensure clean edge triggering. When driven by an external function generator or system clock, the ISL85005EVAL1Z maintains tight duty-cycle control and eliminates beat frequencies in multi-rail systems. This capability is exclusive to the ISL85005 (not ISL85005A) and is fully implemented on the ISL85005EVAL1Z per the device's datasheet timing specifications (t_HI/t_LO ≥100ns, logic thresholds 0.5V/1.2V).