Analog Devices Inc. LTC2935IDC-2

Overview

LTC2935IDC-2 from Analog Devices (formerly Linear Technology) is an ultra-low power voltage supervisor IC with active-pull-up reset and power-fail outputs, configured for 2.40V reset threshold and 2.55V power-fail threshold in industrial temperature range (–40°C to +85°C), housed in an 8-lead 2mm × 2mm DFN package. It delivers 500nA typical quiescent current, ±1.5% threshold accuracy over temperature, and 200ms reset timeout - enabling reliable system initialization and controlled shutdown in battery-powered portable equipment.

For engineers reviewing the LTC2935IDC-2 datasheet, LTC2935IDC-2 pinout, LTC2935IDC-2 application, or LTC2935IDC-2 equivalent, key selection considerations include its active-pull-up RST/PFO outputs (eliminating external pull-ups), pin-selectable thresholds via S2/S1/S0, manual reset input with 200ms debounced release, and guaranteed operation down to 1V supply - critical for coin-cell and Li-ion monitoring designs.

Technical Context

The LTC2935IDC-2 integrates two precision comparators: one for reset generation (VRTF = 2.40V falling, with 5% hysteresis on rising edge) and one for early-warning power-fail detection (VPFT = 2.55V, 150mV above reset threshold). Its internal RC-based reset timer ensures a fixed 200ms RST low-to-high transition after VCC exceeds the reset threshold plus hysteresis.

Threshold selection is implemented via three logic-level inputs (S2, S1, S0) tied to GND or VCC, directly configuring one of eight factory-trimmed reset/power-fail pairs. The MR input features an internal 900kΩ pull-up and 20μs minimum pulse width requirement, supporting pushbutton-initiated system resets without external components.

Key Specifications

Pinout & Package

Package: 8-lead, 2mm × 2mm plastic DFN (DC package) with exposed pad (optional GND connection). Pin pitch: 0.5mm. RoHS-compliant, lead-free finish.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage supervisor applications.

Compared with LTC2935ITS8-2#TRPBF, LTC2935IDC-2 saves 35% board area and improves thermal resistance by 48% (θJA = 102°C/W vs 195°C/W), critical for sealed enclosures. Against LTC2934IDC-2#TRPBF, LTC2935IDC-2 trades adjustability for tighter threshold tolerance and simpler BOM - no external resistors needed.

Availability

LTC2935IDC-2 is available at Aetrix Electronics and suitable for battery-powered portable equipment, coin-cell–powered security sensors, industrial point-of-sale terminals, and Li-ion–powered wireless handhelds requiring stable component supply across extended product lifecycles.

Supply support for LTC2935IDC-2 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 its high-precision analog IC portfolio. Linear pioneered ultra-low-power supervision with sub-μA ICC and factory-trimmed thresholds for mission-critical embedded systems.

The LTC2935 family was designed specifically for battery longevity and deterministic voltage monitoring in portable, medical, and industrial edge devices - emphasizing zero-compromise accuracy, minimal external components, and robust noise immunity.

FAQ

What is the exact reset threshold voltage of the LTC2935IDC-2?

The LTC2935IDC-2 has a nominal reset threshold of 2.40V (VRTF7) with ±1.5% maximum deviation over –40°C to +85°C. This value is factory-trimmed and corresponds to S2 = High, S1 = Low, S0 = High configuration. The power-fail threshold is fixed at 2.55V (150mV above reset), and both thresholds include built-in hysteresis (5% for reset, 2.5% for PFO) to prevent chatter.

Does the LTC2935IDC-2 require external pull-up resistors on RST and PFO?

No. The LTC2935IDC-2 features active-pull-up outputs on both RST and PFO, meaning they drive high to VCC internally - eliminating the need for external pull-up resistors. This reduces BOM count, saves board space, and avoids power loss in pull-up networks. Note: these outputs cannot be pulled above VCC, unlike open-drain variants (e.g., LTC2935-1).

How does the manual reset (MR) function work on the LTC2935IDC-2?

When MR is pulled low (≤0.4V), the LTC2935IDC-2 immediately forces RST low. After MR returns high, RST remains low for a guaranteed 200ms timeout before releasing high. The MR pin has an internal 900kΩ pull-up to VCC and accepts logic-low pulses as short as 20μs. No external components are needed unless ESD protection (e.g., 10kΩ series resistor) is required.

Can the LTC2935IDC-2 operate with supply voltages below 2.4V?

Yes. The LTC2935IDC-2 operates from 1V to 5.5V and functions correctly even when VCC drops below its 2.40V reset threshold - it continues monitoring and holds RST low until VCC rises above 2.52V (2.40V + 5% hysteresis). Its 500nA ICC ensures minimal loading during deep discharge, making it suitable for monitoring dying batteries down to 1.0V.

What is the thermal performance difference between the DFN and TSOT-23 packages for the LTC2935IDC-2?

The LTC2935IDC-2 in 2mm × 2mm DFN (DC package) has θJA = 102°C/W, while the equivalent TSOT-23 variant (LTC2935ITS8-2) has θJA = 195°C/W - nearly double the thermal resistance. The DFN's exposed pad (optional GND connection) significantly improves heat dissipation, making LTC2935IDC-2 preferable for thermally constrained environments or continuous operation near maximum ambient temperature.