Renesas ISL9106IRZ

Overview

ISL9106IRZ from Intersil is a 1.2A, 1.6MHz synchronous buck regulator optimized for low-voltage microprocessor core power in space-constrained portable devices. It delivers 0.8V–3.3V adjustable output from a 2.7V–5.5V input, features 17µA quiescent current in Skip mode, integrated P/N-channel MOSFETs (160mΩ/150mΩ), and 100% duty cycle for ultra-low dropout operation.

For engineers reviewing the ISL9106IRZ datasheet, ISL9106IRZ pinout, ISL9106IRZ application, or ISL9106IRZ equivalent, key selection criteria include light-load efficiency optimization via MODE-selectable PWM/Skip operation, Power-Good timing with RSI reset capability, thermal shutdown at +150°C, and compatibility with single Li+ cell or regulated 5V supplies in compact DFN layouts.

Technical Context

The ISL9106IRZ employs peak-current-mode PWM control with internal slope compensation for fast transient response and pulse-by-pulse overcurrent protection. Its dual-MOSFET architecture integrates a 160mΩ P-Channel high-side switch and 150mΩ N-Channel low-side switch, enabling up to 95% efficiency across 0–1.2A load range.

Operation supports two distinct modes: forced PWM (MODE = SGND) for constant 1.6MHz switching and minimal output ripple, or Skip mode (MODE = VIN) with dynamic frequency reduction and 17µA IQ for battery life extension. The 215ms Power-Good delay is internally generated and resettable via RSI, while soft-start ensures controlled 1.1ms voltage ramp-up.

Key Specifications

Pinout & Package

ISL9106IRZ is housed in a RoHS-compliant 10-lead 3mm×3mm DFN package (L10.3x3C) with exposed thermal pad connected to PGND. The 0.9mm profile supports ultra-thin handheld designs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous buck regulator applications.

Compared with TPS62231DRYR and RT8059GJ6, the ISL9106IRZ offers superior low-input performance (2.7V min), explicit RSI-controlled PG reset for complex sequencing, and proven 1.6MHz stability with 2.2µH inductors-making it ideal for legacy Li+-based portable designs where layout reuse and timing predictability are critical.

Availability

ISL9106IRZ is available at Aetrix Electronics and suitable for mobile baseband power, DSP supply, PDA SoC regulation, and Li+-powered IoT sensor nodes requiring stable component supply with long lifecycle support.

Supply support for ISL9106IRZ 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

Intersil Corporation (now part of Renesas Electronics) is a U.S.-based analog and power management IC designer known for high-efficiency DC-DC solutions targeting portable and battery-powered systems.

The ISL9106IRZ belongs to Intersil's low-IQ synchronous buck regulator product line, engineered specifically for extended battery life and minimal PCB area in handheld consumer electronics like cellular phones and PDAs.

FAQ

What is the minimum input voltage required for ISL9106IRZ to regulate a 1.2V output?

The ISL9106IRZ maintains regulation down to VIN = VOUT + IOUT × RDS(ON)_PCH. At 1.2A load, with typical 160mΩ P-channel ON-resistance, dropout voltage is ~192mV. Thus, minimum functional VIN is ~1.392V - but the device's UVLO (2.5V rising) prevents operation below 2.5V. Therefore, ISL9106IRZ requires ≥2.7V input to both enable and regulate a 1.2V output.

How does the RSI pin affect Power-Good timing in ISL9106IRZ?

The RSI pin resets the ISL9106IRZ's internal 215ms Power-Good timer. When RSI is high, PG remains low regardless of output voltage. A high-to-low transition on RSI restarts the 215ms counter only if VOUT is within the ±3% regulation window (0.78–0.82V at FB). This allows precise system-level synchronization of power sequencing events independent of initial startup conditions.

Can ISL9106IRZ operate without an external feedback resistor divider?

No. The ISL9106IRZ requires an external resistor divider on the FB pin to set output voltage, as its internal reference is fixed at 0.8V. For fixed 0.8V output, R2 = 0Ω and R3 = 100kΩ is specified in Table 1. Omitting the divider disables regulation - the FB pin has only 0.1µA bias current and cannot self-bias; leaving it open causes undefined output behavior.

What thermal performance can be expected from ISL9106IRZ in a 3mm×3mm DFN package?

With proper PCB layout - including full connection of the exposed thermal pad to a ≥1cm² PGND copper plane - the ISL9106IRZ achieves θJA ≈ 44°C/W and θJC ≈ 5.5°C/W. At 1.2A load and 3.6V input, typical power dissipation is ~250mW; this yields ~11°C junction-to-ambient rise above ambient, well within the -40°C to +125°C operating range and below the +150°C thermal shutdown threshold.

Does ISL9106IRZ support automatic mode transition between PWM and Skip operation?

Yes. When MODE is tied to VIN (or logic high), ISL9106IRZ automatically transitions between forced PWM and Skip mode based on load. It enters Skip mode after detecting eight consecutive zero-crossings of the N-channel MOSFET current - a condition occurring only at light loads (<~100mA). Under heavy load, it remains in continuous PWM; no external control is needed for seamless mode switching.