Analog Devices Inc. LT1161IN#PBF

Overview

LT1161IN#PBF from Analog Devices (formerly Linear Technology) is a quad protected high-side N-channel MOSFET driver IC designed for industrial, avionics, and automotive power switching applications. It features four independent channels, each with an integrated charge pump (750 kHz), individual short-circuit protection, programmable current limit (65 mV threshold), automatic restart timers, and flowthrough pinout. It operates from 8V to 48V supply and withstands –15V to 60V supply transients.

For engineers reviewing the LT1161IN#PBF datasheet, LT1161IN#PBF pinout, LT1161IN#PBF application, or LT1161IN#PBF equivalent, this page delivers verified technical context, real-world timing behavior (e.g., 100–400 µs turn-on at 24V), gate drive voltage above V+ (4–14 V), drain sense threshold (50–80 mV), and thermal performance across –40°C to 85°C operation.

Technical Context

The LT1161IN#PBF implements four fully self-contained high-side gate drivers, each integrating a 750 kHz charge pump to generate gate voltage up to 14 V above V+, enabling full enhancement of standard N-channel MOSFETs without external components. Each channel includes a supply-referenced drain sense comparator with 65 mV nominal threshold and +0.33%/°C temperature coefficient.

Protection logic is per-channel: when sense voltage exceeds threshold, the gate is pulled low within 25–50 µs, the timer pin is discharged, and a 14 µA current source recharges CT to 3 V to initiate automatic restart. Input pins feature TTL/CMOS-compatible thresholds (1.4 V typical), 200 mV hysteresis, and internal 75 kΩ pull-downs; timer pins default high via 14 µA pull-up.

Key Specifications

Pinout & Package

LT1161IN#PBF is supplied in a 20-lead plastic DIP (N package), with dual ground (pins 1, 10) and dual supply (pins 11, 20) pins internally connected and requiring external tie-together. Pinout follows flowthrough layout: inputs (IN1–IN4) and timers (T1–T4) are on one side; gates (G1–G4), senses (DS1–DS4), and supplies (V+) on the opposite side.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-side MOSFET driver applications.

Compared with LT1910CS8#TRPBF and TPS2H160-Q1, the LT1161IN#PBF uniquely offers per-channel programmable restart timing via external capacitors, flowthrough pinout for noise-sensitive routing, and guaranteed –15V to 60V supply survivability - making it optimal for ruggedized multi-load industrial systems.

Availability

LT1161IN#PBF is available at Aetrix Electronics and suitable for industrial motor control, avionics power distribution, and automotive body electronics requiring stable component supply across extended temperature and harsh electrical environments.

Supply support for LT1161IN#PBF 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

Analog Devices, Inc. (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and power management semiconductors.

The LT1161 product line was developed specifically for ruggedized high-side power switching in industrial, avionics, and automotive systems - emphasizing transient immunity, per-channel protection autonomy, and simplified system-level current sensing.

FAQ

What is the absolute maximum supply voltage rating for the LT1161IN#PBF?

The LT1161IN#PBF is rated for –15V to +60V on its V+ pins (11 and 20). This rating is 100% tested and guaranteed - exceeding 60V, even momentarily, risks catastrophic failure. The device's internal protection architecture allows safe operation across automotive load-dump and industrial surge conditions without external clamping diodes.

How does the LT1161IN#PBF implement current limiting and automatic restart?

The LT1161IN#PBF uses a per-channel drain sense comparator with a 65 mV nominal threshold. When the voltage across the external sense resistor exceeds this level, the gate is turned off within 25–50 µs. A 14 µA current source then recharges the external timing capacitor (CT) to 3 V, triggering automatic restart. This cycle repeats until the fault clears - enabling self-recovery without microcontroller intervention.

Can the LT1161IN#PBF drive standard N-channel MOSFETs at 8V supply?

At 8V supply, the LT1161IN#PBF's charge pump may not generate sufficient gate voltage to fully enhance standard N-channel MOSFETs (typically requiring >10 V VGS). However, logic-level MOSFETs with VGS(th) ≤ 2 V and VGS(max) ≥ 15 V are fully supported down to 8V - enabling compatibility with low-voltage industrial and automotive systems.

What is the purpose of the dual V+ and GND pins on the LT1161IN#PBF?

The dual V+ (pins 11, 20) and dual GND (pins 1, 10) pins on the LT1161IN#PBF are internally connected and must be externally tied together. This configuration establishes a Kelvin connection for the drain sense comparators - ensuring accurate current measurement by referencing the sense inputs directly to the supply rail at the sense resistor's positive terminal.

Is the LT1161IN#PBF pin-compatible with other variants like LT1161CN or LT1161ISW?

Yes - all LT1161 variants (including LT1161IN#PBF, LT1161CN, LT1161ISW, LT1161CSW) share identical pinouts and electrical specifications. The suffix denotes temperature grade (I = –40°C to +85°C) and package (N = PDIP, SW = SOIC). LT1161IN#PBF is the lead-free, industrial-grade DIP version; no PCB layout changes are needed when substituting within the same package type.