Analog Devices Inc. LTC1442IS8#PBF

Overview

LTC1442IS8#PBF from Analog Devices (formerly Linear Technology) is an ultralow-power dual comparator with integrated 1.182V ±1% reference, programmable hysteresis via HYST pin, TTL/CMOS-compatible rail-to-rail outputs, and 3.5µA typical supply current at –40°C to +85°C. It operates from single 2V–11V or dual ±1V–±5.5V supplies and is used in battery-powered voltage monitoring and precision threshold detection circuits.

For engineers reviewing the LTC1442IS8#PBF datasheet, LTC1442IS8#PBF pinout, LTC1442IS8#PBF application, or LTC1442IS8#PBF equivalent, key selection factors include its dual-comparator architecture with shared reference, hysteresis configurability, guaranteed input common-mode range to V– and within 1.3V of V+, and output sourcing capability up to 40mA without crowbar current.

Technical Context

The LTC1442IS8#PBF integrates two independent comparators sharing a single internal 1.182V bandgap reference referenced to V–, with dedicated HYST and REF pins enabling external hysteresis programming using two resistors. Its input stage supports operation down to the negative supply rail and up to V+ – 1.3V, while outputs swing rail-to-rail between V– and V+ with no crowbar current during transitions.

Unlike the LTC1440 (which includes GND pin for TTL-level output referencing), the LTC1442IS8#PBF uses V– as the output low reference, making it suitable for true dual-supply or floating-ground applications. The reference can drive up to 0.01µF bypass capacitance without oscillation and maintains ±1% accuracy over –40°C to +85°C.

Key Specifications

Pinout & Package

Package: 8-lead plastic SO (S8), 150°C max junction temperature, θ_JA = 175°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual comparator with reference applications.

Compared with LTC1442CS8#PBF, the LTC1442IS8#PBF guarantees operation over industrial temperature and offers higher reliability in thermal-cycling environments; versus LTC1540IDDB#PBF, it provides dual channels and external hysteresis control at the cost of ~10× higher supply current - a justified trade-off for system-level simplicity and responsiveness.

Availability

LTC1442IS8#PBF is available at Aetrix Electronics and suitable for battery-powered system monitoring, threshold detectors, and window comparators requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for LTC1442IS8#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 acquired Linear Technology in 2017 and maintains full technical and manufacturing continuity for legacy Linear products including the LTC144x family.

The LTC1442IS8#PBF belongs to Linear's micropower comparator with reference product line, designed specifically for energy-constrained applications where precision, integration, and ultra-low quiescent current are critical - such as portable instrumentation, remote sensors, and backup power supervisors.

FAQ

What is the maximum hysteresis voltage band achievable with LTC1442IS8#PBF?

The LTC1442IS8#PBF supports a maximum hysteresis voltage band of 100mV, derived from a 50mV range on the HYST pin relative to the 1.182V reference (REF – 50mV to REF). This is implemented using two external resistors forming a divider from REF to V–, with R1 connected between REF and HYST. The LTC1442IS8#PBF datasheet specifies this limit to ensure stability and monotonic threshold behavior across temperature.

Can LTC1442IS8#PBF operate from a single 2.5V supply?

Yes, LTC1442IS8#PBF operates from a single 2.5V supply, but note that the input common-mode range extends only to V+ – 1.3V = 1.2V. Since the internal 1.182V reference falls within this range, valid comparator operation is maintained. However, output swing is limited to V– (typically GND) to 2.5V, and reference regulation may degrade slightly below 2.7V per Linear's application notes. The LTC1442IS8#PBF remains functional but with reduced noise margin at 2.5V.

Does LTC1442IS8#PBF require external pull-up resistors on its outputs?

No, LTC1442IS8#PBF does not require external pull-up resistors. Its outputs are push-pull CMOS structures capable of sourcing up to 40mA and sinking up to 5mA, swinging rail-to-rail between V– and V+. Pull-ups are unnecessary unless interfacing with open-drain buses or level-shifting to higher voltages - in which case the LTC1442IS8#PBF output must be isolated via a series resistor or buffer to avoid violating absolute maximum ratings.

How is the reference output of LTC1442IS8#PBF affected by load current?

The LTC1442IS8#PBF reference output exhibits a maximum deviation of ±5mV over a sink/source load range of 0–200µA, per Electrical Characteristics table. At 100µA source current, ∆VREF is typically < 2mV. This tight regulation allows direct connection to high-impedance comparator inputs without gain error, and supports driving 0.01µF bypass capacitors without oscillation - a key design advantage confirmed in Figure G11/G12 of the LTC1442IS8#PBF datasheet.

Is LTC1442IS8#PBF pin-compatible with MAX922?

No, LTC1442IS8#PBF is not pin-compatible with MAX922. While both are dual comparators with reference, MAX922 uses a different pinout: OUTA/V+/INB+/INB–/GND/INB–/V–/OUTB (non-standard assignment), whereas LTC1442IS8#PBF uses OUTA/V–/INA+/INB–/HYST/REF/V+/OUTB. Substituting MAX922 would require PCB redesign. The LTC1442IS8#PBF datasheet explicitly lists pin-compatible upgrades only for MAX921/922/923 *in the LTC1440 configuration*, not LTC1442.