Renesas ISL91107IRTNZ

Overview

ISL91107IRTNZ from Renesas Electronics (formerly Intersil) is a fixed 3.3V-output, high-efficiency buck-boost DC/DC regulator with fully synchronous 4-switch architecture, 2.5MHz switching frequency, 1.8V–5.5V input range, and 2A output capability at PVIN = 2.8V. It delivers seamless automatic mode transitions between buck and boost for stable power in portable battery-powered systems.

For engineers reviewing the ISL91107IRTNZ datasheet, ISL91107IRTNZ pinout, ISL91107IRTNZ application, or ISL91107IRTNZ equivalent, this evaluation board enables rapid validation of the ISL91107IRTNZ's 3.3V fixed-output buck-boost performance under real-world load transients, line regulation, and thermal conditions - critical for smartphone, tablet, and optical module power design.

Technical Context

The ISL91107IRTNZ is an evaluation board designed exclusively for the ISL91107IRTNZ IC - a monolithic buck-boost regulator featuring integrated 4.1A MOSFET switches, dual ground separation (SGND/PGND), and programmable MODE pin for PFM/PWM selection. Its reference design uses a single 1µH inductor and 2×22µF X5R output capacitors to achieve >95% peak efficiency at 3.3V/1A with VIN = 3.6V.

This board implements the exact schematic shown in Figure 1 of FN8687 Rev 0.00, including PVIN and VIN decoupling (22µF each), FB resistor network omitted (fixed 3.3V version), and thermal pad connected to PGND. It supports full characterization of soft-start (2ms buck / 3ms boost), soft-discharge (35Ω internal pull-down), and thermal shutdown (150°C trip, 30°C hysteresis).

Key Specifications

Availability

ISL91107IRTNZ is available at Aetrix Electronics and suitable for smartphone power management, tablet PC PMIC validation, and optical module voltage regulation requiring stable component supply and fast time-to-test.

Supply support for ISL91107IRTNZ 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 analog, power management, and embedded processing solutions for industrial, automotive, and consumer applications.

The ISL91107IRTNZ evaluation board belongs to Renesas' precision power management product line, engineered specifically to accelerate adoption of high-efficiency buck-boost regulators in space-constrained, battery-sensitive portable electronics.

FAQ

What is the ISL91107IRTNZ evaluation board used for?

The ISL91107IRTNZ evaluation board is a ready-to-use hardware platform designed to validate the electrical performance, thermal behavior, and system integration of the ISL91107IRTNZ fixed 3.3V buck-boost regulator IC. It implements the exact reference circuit from the FN8687 datasheet, enabling engineers to measure efficiency, transient response, soft-start timing, and protection features without custom PCB development. The board supports direct probing of all key nodes - PVIN, VIN, VOUT, LX1, LX2, EN, MODE, and FB - for comprehensive characterization of the ISL91107IRTNZ in real operating conditions.

Does the ISL91107IRTNZ evaluation board support adjustable output voltages?

No, the ISL91107IRTNZ evaluation board is configured exclusively for the fixed 3.3V output version of the ISL91107IRTNZ IC. It does not include external feedback resistors or jumpers for voltage adjustment. For variable output testing, users must select the ISL91107IRTAZ evaluation board (ISL91107IRA-EVZ), which supports the adjustable version using an R1/R2 divider network. The ISL91107IRTNZ board's layout and component values - including the absence of FB resistors and use of 2×22µF output capacitors - are optimized specifically for 3.3V operation as defined in the ISL91107IRTNZ ordering specification.

What input voltage range can be applied to the ISL91107IRTNZ evaluation board?

The ISL91107IRTNZ evaluation board accepts 1.8V to 5.5V on both PVIN and VIN pins, matching the absolute maximum and recommended operating ranges specified for the ISL91107IRTNZ IC in FN8687 Rev 0.00. This dual-input architecture allows independent biasing: PVIN supplies the power stage while VIN powers the internal reference and control circuitry. The board includes 22µF input capacitors on each rail and is validated to deliver stable 3.3V output across this full range - including critical regions where VIN ≈ VOUT (e.g., 3.0V–3.6V), where seamless buck-to-boost transition is essential.

How is thermal performance validated on the ISL91107IRTNZ evaluation board?

The ISL91107IRTNZ evaluation board validates thermal performance through its implementation of the IC's thermal pad (EPAD) directly soldered to a large PGND copper area, enabling measurement of junction-to-case (θJC = 5.5°C/W) and junction-to-ambient (θJA = 41°C/W) thermal resistance per datasheet specifications. Users can monitor die temperature via the IC's thermal shutdown feature (trip at +150°C, recovery at +120°C) and correlate it with board surface temperatures using thermocouples placed near the TQFN package. The board's layout follows Renesas' recommended guidelines - short high-current paths, separated SGND/PGND planes, and optimized thermal vias - ensuring accurate thermal characterization of the ISL91107IRTNZ under sustained 2A loads.

Can the ISL91107IRTNZ evaluation board demonstrate soft-start and soft-discharge behavior?

Yes, the ISL91107IRTNZ evaluation board fully demonstrates both soft-start and soft-discharge functions of the ISL91107IRTNZ IC. Soft-start timing (1ms delay after EN assertion, then 2ms for buck mode or 3ms for boost mode ramp to 95% VOUT) is observable at the VOUT node using an oscilloscope. Soft-discharge is activated when EN is pulled LOW, engaging an internal 35Ω resistor between VOUT and SGND - measurable as controlled VOUT decay with typical discharge time constants dependent on output capacitance. These behaviors are verified using the exact component values (1µH inductor, 2×22µF output caps) and layout described in Figure 1 and Page 11 of FN8687, confirming the ISL91107IRTNZ's ability to minimize inrush current and prevent output voltage hang-up during enable/disable cycles.