Analog Devices Inc. LTC2917CMS-A1#PBF

Overview

LTC2917CMS-A1#PBF from Analog Devices (formerly Linear Technology) is a low-voltage supervisor IC with 9 selectable nominal thresholds (12V to ADJ/0.5V), ±5%/±10%/±15% tolerance selection via TOL pin, and adjustable reset timeout. It operates from 1.5V to 5.5V supply, consumes 30μA typical quiescent current, guarantees ±1.5% threshold accuracy over –40°C to 125°C, and delivers reliable reset assertion for microprocessor power sequencing in automotive control systems.

For engineers reviewing the LTC2917CMS-A1#PBF datasheet, LTC2917CMS-A1#PBF pinout, LTC2917CMS-A1#PBF application, or LTC2917CMS-A1#PBF equivalent, key selection criteria include its three-state SEL1/SEL2/TOL voltage configuration interface, internal 200ms fixed reset timeout (RT = VCC), windowed watchdog capability (B-version only - excluded here), and guaranteed RST assertion down to VCC ≥ 0.8V during power-up sequencing.

Technical Context

The LTC2917CMS-A1#PBF implements a precision comparator-based voltage monitor with internally trimmed reference and programmable hysteresis via TOL pin selection. Its VM input accepts direct connection to monitored supplies or external resistive dividers for ADJ mode, with input impedance ranging 0.5–8 MΩ depending on SEL pin state.

Reset timing is controlled by RT pin configuration: open (≈400μs), tied to VCC (≈200ms), or capacitor-coupled to GND (9 ms/nF). The device features glitch immunity with <150μs minimum detectable undervoltage pulse width and guaranteed operation up to 125°C ambient temperature.

Key Specifications

Pinout & Package

Package: 10-Lead Plastic MSOP (3mm × 3mm), 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 MAX6326US29D3+T and TPS3808G33DBVR, the LTC2917CMS-A1#PBF offers unique configurability across nine voltage levels and three tolerances in a single 10-pin MSOP, making it optimal for multi-rail systems where board space permits and flexibility justifies higher unit cost.

Availability

LTC2917CMS-A1#PBF is available at Aetrix Electronics and suitable for automotive engine control units, industrial PLC modules, medical infusion pump controllers, and telecom baseband processor boards requiring stable component supply with guaranteed 0°C to 70°C operation.

Supply support for LTC2917CMS-A1#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 digital signal processing semiconductors.

The LTC2917 family was designed specifically for robust, configurable power supply monitoring in harsh environments - emphasizing precision threshold accuracy, wide temperature operation, and glitch-immune reset generation for mission-critical embedded systems.

FAQ

What is the function of the TOL pin on the LTC2917CMS-A1#PBF?

The TOL pin on the LTC2917CMS-A1#PBF selects the tolerance band applied to the selected nominal threshold: VCC sets –5%, open sets –10%, and GND sets –15%. This allows precise alignment of the reset trip point relative to the monitored supply's specified tolerance, ensuring reliable detection without nuisance resets. The LTC2917CMS-A1#PBF uses this pin to configure hysteresis for each of its nine selectable voltage thresholds.

Does the LTC2917CMS-A1#PBF support windowed watchdog functionality?

No, the LTC2917CMS-A1#PBF does not support windowed watchdog functionality. That feature is exclusive to B1 versions (e.g., LTC2917CMS-B1#PBF). The A1 version implements standard watchdog timing with only an upper boundary timeout (tWDU); falling edges on WDI must occur before tWDU expires to prevent reset assertion, but no lower-bound enforcement occurs. The LTC2917CMS-A1#PBF watchdog remains active unless WT and WDI are both tied to GND.

What is the maximum supply voltage that can be applied to the VCC pin of the LTC2917CMS-A1#PBF?

The absolute maximum VCC pin voltage for the LTC2917CMS-A1#PBF is 5.7V when sourced from a low-impedance supply. For higher-voltage supplies (e.g., 12V), the internal 6.2V shunt regulator must be used with a series current-limiting resistor to keep VCC pin current ≤5mA. Exceeding 5.7V without current limiting risks violating terminal current ratings. The LTC2917CMS-A1#PBF datasheet specifies this constraint explicitly in Absolute Maximum Ratings.

How is the reset timeout configured on the LTC2917CMS-A1#PBF when using the RT pin?

On the LTC2917CMS-A1#PBF, the RT pin configures reset timeout as follows: leaving RT open yields ≈400μs, tying RT to VCC yields ≈200ms, and connecting a capacitor (CRT) from RT to GND gives tRST ≈ 9 ms/nF (e.g., 2.2nF → 20ms). The LTC2917CMS-A1#PBF does not require external components for basic operation - the 200ms setting is commonly used for microprocessor initialization sequences.

Can the LTC2917CMS-A1#PBF monitor a 12V supply directly?

Yes, the LTC2917CMS-A1#PBF can monitor a 12V supply directly using its ADJ mode: connect VM to a resistive divider (e.g., R1=49.9kΩ, R2=1.15MΩ) to scale 12V down to 0.5V at VM, then set SEL1=SEL2=GND. The internal comparator references 0.5V, so the trip point becomes 12V × (1 + R2/R1) = 12V. The LTC2917CMS-A1#PBF supports this configuration with ±1.5% accuracy over temperature, and its VCC pin can handle 12V via the internal shunt regulator with proper series resistance.