Renesas ISL6127IR-T

Overview

ISL6127IR-T from Renesas (formerly Intersil) is a pre-programmed 4-channel power-supply sequencer IC for controlled turn-on (A-B-C-D) and turn-off (D-C-B-A) of voltage rails in multi-rail systems. It operates from 1.5V to 5.5V supply, delivers VDD +5.3V gate drive, supports undervoltage lockout monitoring on all four rails, and asserts a 160ms-delayed RESET signal after full sequencing completion. It is used in FPGA/ASIC power-up sequencing where deterministic order and fault-safe shutdown are required.

For engineers reviewing the ISL6127IR-T datasheet, ISL6127IR-T pinout, ISL6127IR-T application, or ISL6127IR-T equivalent, key selection criteria include its fixed A-B-C-D/D-C-B-A sequence logic, absence of external delay capacitors, 24-lead QFN package, 0.633V UVLO reference with 10ms enable lockout, and compatibility with external N-channel MOSFETs for rail control.

Technical Context

The ISL6127IR-T implements a hardwired sequencing state machine: turn-on begins only after all four UVLO inputs exceed 0.633V and ENABLE is asserted, then GATE_A ramps first, followed by GATE_B once GATE_A reaches ~VDD+4.9V, then GATE_C, then GATE_D. Turn-off follows strict D-C-B-A order upon ENABLE deassertion, with each GATE pulled low only after the prior one drops below 0.6V.

No external timing capacitors are required-sequencing delays are internally fixed and non-adjustable. The device uses a micropower 7× charge pump to generate VDD+5.3V gate drive for external NFETs, and includes glitch-immune UVLO comparators with 30µs filtering and open-drain RESET/SYSRST outputs compatible down to VDD = 1V.

Key Specifications

Pinout & Package

ISL6127IR-T is housed in a 24-lead, 4mm × 4mm, 0.5mm pitch QFN package (Pb-free, RoHS-compliant) with exposed thermal pad. Pin functions are validated per FN9005 Rev 1.00, Page 3 (ISL6127 top view) and Page 4 (pin descriptions).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar power supply sequencing applications.

Compared with ISL6127IR-T, ISL6124IRZA-T offers flexibility at the cost of component count and layout sensitivity, while TPS652860RHAR trades sequencing-only simplicity for integrated power conversion-making ISL6127IR-T optimal for designs prioritizing deterministic timing, minimal external parts, and proven reliability in established multi-rail architectures.

Availability

ISL6127IR-T is available at Aetrix Electronics and suitable for FPGA/ASIC power sequencing, telecom line card startup, and network router multi-rail control requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for ISL6127IR-T 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 (formerly Intersil) is a global semiconductor leader specializing in analog, mixed-signal, and power management ICs for industrial, automotive, and communications markets.

The ISL6127IR-T belongs to the ISL612X family of precision power sequencers designed specifically for deterministic, fault-tolerant voltage rail sequencing in high-reliability digital systems such as FPGAs, ASICs, and telecom infrastructure.

FAQ

What is the sequencing behavior of the ISL6127IR-T during power-up?

The ISL6127IR-T initiates A-B-C-D turn-on only after all four UVLO inputs exceed 0.633V and ENABLE_1 is asserted low for ≥10ms. GATE_A begins ramping first; GATE_B starts only after GATE_A reaches ~VDD+4.9V; similarly, GATE_C follows GATE_B, and GATE_D follows GATE_C. No external capacitors are involved-the delays are fixed and internal.

Does the ISL6127IR-T support adjustable sequencing delays?

No. Unlike ISL6123/ISL6124 variants, the ISL6127IR-T has pre-programmed, non-adjustable sequencing timing. DLY_ON and DLY_OFF pins are NC-no external capacitors can be connected to modify turn-on or turn-off delays. This ensures consistent, repeatable behavior across units and temperatures.

How does the ISL6127IR-T handle undervoltage faults during operation?

When any UVLO input falls below 0.633V for longer than 30µs, the ISL6127IR-T immediately pulls RESET and SYSRST low and simultaneously sinks >88mA on all four GATE pins to force rapid FET turn-off. This provides robust fault containment without requiring external supervision circuitry.

Can multiple ISL6127IR-T devices be cascaded for more than four rails?

Yes. Connect SYSRST outputs to ENABLE_1 inputs of downstream ISL6127IR-T units. When the first device detects a fault or completes sequencing, it drives SYSRST low or high, respectively, triggering the next device-enabling scalable, synchronized sequencing across dozens of rails with deterministic inter-device timing.

What is the maximum gate capacitance the ISL6127IR-T can drive reliably?

The ISL6127IR-T specifies 1.1µA typical GATE turn-on current and >88mA pull-down capability during fault shutdown. For reliable 10%–90% ramp times under 1ms, gate capacitance should remain ≤10nF per channel. Larger FETs require verifying rise/fall times in prototype testing with actual load conditions.