STMicroelectronics STM692AM6F

Overview

STM692AM6F from STMicroelectronics is a 5 V microprocessor supervisory IC with battery switchover, NVRAM supervision for external LPSRAM, dual active-low and active-high reset outputs (RST/RST), 200 ms typical reset timeout (trec), and integrated watchdog timer (1.6 s typical timeout). It operates across –40 °C to +85 °C and supports industrial embedded systems requiring reliable power monitoring and SRAM backup during main supply failure.

For engineers reviewing the STM692AM6F datasheet, STM692AM6F pinout, STM692AM6F application, or STM692AM6F equivalent, key selection criteria include guaranteed RST assertion down to VCC = 1.0 V, low battery supply current (0.4 µA typ), automatic VCC-to-VBAT switchover at VSO, push-pull reset outputs, and compatibility with external LPSRAM write-protection schemes.

Technical Context

The STM692AM6F integrates a precision voltage reference and comparator to monitor VCC against a fixed reset threshold (VRST ≈ 4.63 V), asserting RST/RST when VCC drops below VRST or after MR activation or watchdog timeout. Its internal P-channel MOSFET switch enables seamless VOUT switchover from VCC to VBAT when VCC falls below the lesser of VBAT and VRST, with 100 Ω on-resistance and hysteresis-enabled reconnection.

It features a 1.6 s typical watchdog timer cleared by WDI edge transitions (≥50 ns), disabled when WDI floats; push-pull RST/RST outputs guarantee valid logic states down to VCC = 1.0 V without battery or down to VBAT > 1 V with battery; and includes dedicated PFI/PFO for early power-fail detection with VPFI ≈ 2.4 V threshold and <10 µs propagation delay.

Key Specifications

Pinout & Package

The STM692AM6F is housed in an 8-pin SO8 (Small Outline) package with standard 1.27 mm pitch, JEDEC MS-012AC compliant outline, and surface-mount footprint optimized for automated assembly and thermal reliability.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX692AESA+ and TPS3823MPW, the STM692AM6F uniquely integrates battery switchover, dual reset outputs, and PFI/PFO in a single SO8 package-enabling compact, self-contained NVRAM supervision without supplemental ICs or discrete FETs.

Availability

STM692AM6F is available at Aetrix Electronics and suitable for industrial PLC controllers, medical infusion pumps, smart energy meters, and automotive telematics units requiring stable component supply with guaranteed long-term availability and RoHS-compliant packaging.

Supply support for STM692AM6F 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, MCU, power, and sensor solutions for industrial, automotive, and consumer markets.

The STM69x/70x/80x supervisor family targets industrial and medical systems needing robust, integrated power monitoring and non-volatile memory protection-specifically addressing SRAM backup, watchdog safety, and deterministic reset timing in harsh environments.

FAQ

What is the minimum VCC voltage at which RST remains guaranteed active?

RST is guaranteed to assert and remain valid down to VCC = 1.0 V when no backup battery is present. With VBAT > 1 V connected, RST remains asserted even if VCC drops to 0 V, ensuring uninterrupted reset signaling during complete main supply failure.

How does the battery switchover mechanism prevent premature battery drain?

The device implements a battery freshness seal: VOUT remains disconnected from VBAT until VCC first exceeds VRST after power-up. This prevents battery discharge during storage, shipment, or factory test-extending shelf life and enabling "first-use activation" of backup power.

Can the watchdog timer be disabled without modifying the PCB layout?

Yes-the watchdog function is automatically disabled when the WDI pin is left floating (high-impedance). No pull-up/down resistor or jumper is required; the internal leakage specification (<10 µA) ensures reliable disable behavior with standard PCB parasitics.

Is the PFI input compatible with direct connection to a 3.3 V rail?

Yes-PFI accepts 0–5.5 V inputs and triggers PFO when voltage falls below 2.4 V. Connecting directly to a 3.3 V rail provides ~0.9 V noise margin, enabling reliable early-warning detection of 3.3 V regulator failure without scaling resistors.