Renesas ISL9120IIA-EVZ

Overview

ISL9120IIA-EVZ from Renesas Electronics is an evaluation board designed specifically for the ISL9120IIAZ adjustable-output buck-boost regulator IC. It enables rapid validation of the 1.8V–5.5V input, 1.0V–5.2V programmable output, 800mA-capable switching regulator in real-world portable power applications. The board implements the recommended 1µH inductor, 10µF input and 47µF output ceramic capacitors, and full external resistor divider (R1 = 187kΩ, R2 = 60.4kΩ) to deliver a nominal 3.3V output.

For engineers reviewing the ISL9120IIA-EVZ datasheet, ISL9120IIA-EVZ pinout, ISL9120IIA-EVZ application, or ISL9120IIA-EVZ equivalent, this evaluation platform supports immediate functional verification of forced bypass mode operation, PFM efficiency optimization across light-to-heavy loads, soft-start timing, load transient response, and thermal shutdown behavior under varying VIN–VOUT differentials.

Technical Context

The ISL9120IIA-EVZ implements the complete reference design for the ISL9120IIAZ IC, including its dual-mode buck-boost topology with automatic mode transition, adaptive multilevel current limit (32 levels, 350mA–2A), and integrated 50mΩ P-channel/N-channel MOSFETs. It validates the IC's ability to maintain regulation when VIN crosses VOUT - e.g., stepping up from 2.5V to 3.3V or stepping down from 4.0V to 3.3V - without output disturbance.

This board exposes all critical control signals: EN for enable/disable with 1ms soft-start delay, BYP for forced bypass entry/exit (minimum 800µs active, 1ms recovery), and FB for feedback loop tuning. It incorporates the required GND guard band around the FB network and uses X5R ceramic capacitors meeting 0603 size, 6.3V/10V rating, and low-ESR specifications per datasheet recommendations.

Key Specifications

Availability

ISL9120IIA-EVZ is available at Aetrix Electronics and suitable for smartphone power architecture validation, wearable device battery voltage stabilization, and portable medical sensor subsystem testing requiring stable component supply and rapid prototyping capability.

Supply support for ISL9120IIA-EVZ 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 high-performance microcontrollers, analog power, and mixed-signal solutions for automotive, industrial, and consumer markets.

The ISL9120 product line delivers compact, high-efficiency buck-boost regulators targeting space-constrained portable electronics where input voltage varies widely relative to system rail requirements.

FAQ

What is the primary purpose of the ISL9120IIA-EVZ evaluation board?

The ISL9120IIA-EVZ evaluation board is a fully assembled and tested hardware platform designed exclusively to evaluate the ISL9120IIAZ adjustable-output buck-boost regulator IC. It implements Renesas' recommended circuit layout, component selection (including 1µH inductor, 10µF/47µF X5R ceramics, and 187kΩ/60.4kΩ FB divider), and signal access points to validate regulation accuracy, efficiency, transient response, bypass functionality, and protection features under real operating conditions.

Does the ISL9120IIA-EVZ support both fixed and adjustable output configurations?

No - the ISL9120IIA-EVZ is configured specifically for the ISL9120IIAZ (adjustable version) and uses an external resistor divider (R1 = 187kΩ, R2 = 60.4kΩ) to set a nominal 3.3V output. It does not support the fixed-output ISL9120IINZ variant, which requires direct VOUT-to-FB connection. The board's FB node is accessible for reconfiguration to other output voltages within the 1.0V–5.2V range per Equation 1 in the datasheet.

How is forced bypass mode activated and verified on the ISL9120IIA-EVZ?

Forced bypass mode on the ISL9120IIA-EVZ is activated by applying a logic-high signal (>1.4V) to the BYP test point while the device is enabled (EN = HIGH). During bypass, VIN connects directly to VOUT through internal switches and the external inductor, reducing quiescent current to ≤3.5µA. Verification is performed by measuring VOUT ripple (<10mVpp), monitoring current draw with a µA-range ammeter, and confirming absence of switching waveforms on LX1/LX2 using an oscilloscope.

What input and output capacitor values are used on the ISL9120IIA-EVZ board?

The ISL9120IIA-EVZ uses a 10µF X5R ceramic capacitor (0603, 10V rating) at the VIN input and a 47µF X5R ceramic capacitor (0603, 6.3V rating) at the VOUT output, matching the datasheet's recommended values and minimum specifications for ESL, ESR, and temperature stability. These values were selected to ensure stable PFM operation, meet load transient requirements (0–500mA step), and minimize output voltage deviation (<±1.5%) across the full input range.

Can the ISL9120IIA-EVZ be used to characterize thermal performance of the ISL9120IIAZ IC?

Yes - the ISL9120IIA-EVZ provides direct access to the IC's thermal pad (connected to PGND) and includes layout features aligned with the W3x3.9E package's θJA = 95°C/W and θJB = 27°C/W specifications. Users can apply controlled load currents (up to 800mA), monitor die temperature via thermal shutdown activation at ~150°C, and measure recovery hysteresis (~115°C) using the board's exposed PGND and VOUT test points with calibrated thermocouples or IR imaging.