STMicroelectronics STM706AM6F

Overview

STM706AM6F from STMicroelectronics is an industrial-grade 5 V microprocessor supervisory IC with precision V_CC monitoring (4.25–4.50 V reset threshold), active-low and active-high RST outputs, watchdog timer (1.6 s typical timeout), manual reset input (MR), and power-fail comparator (PFI/PFO). It guarantees RST assertion down to V_CC = 1.0 V and operates from –40 °C to +85 °C in TSSOP-8 package - used for reliable reset control in embedded controllers, industrial PLCs, and power management subsystems.

For engineers reviewing the STM706AM6F datasheet, STM706AM6F pinout, STM706AM6F application, or STM706AM6F equivalent, key selection considerations include its dual-reset output polarity, guaranteed low-voltage reset assertion, watchdog integration without external components, and automotive-grade temperature option availability (STM706 only).

Technical Context

The STM706AM6F integrates a precision voltage reference comparator for V_CC monitoring, a 1.6 s watchdog timer with WDI/WDO interface, and independent power-fail detection (VPFI = 1.25 V typ) with push-pull PFO output. Its dual RST outputs support both active-low and active-high MCU reset interfaces simultaneously.

Reset assertion is guaranteed down to V_CC = 1.0 V across temperature, and t_rec = 200 ms (typ) ensures stable deassertion timing after power-up or MR release. The MR input includes an internal 40 kΩ pull-up, enabling direct switch connection without external biasing.

Key Specifications

Pinout & Package

STM706AM6F is housed in a 3 × 3 mm TSSOP-8 package (JEDEC MO-153, variant DS), with gull-wing leads and 0.65 mm pitch. Pin 1 marked by dot; pin numbering follows standard counter-clockwise convention from top-left corner.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX692AESA+ and TPS3808G33DBVR, STM706AM6F delivers integrated watchdog, dual-polarity reset, and independent power-fail detection in a space-efficient TSSOP-8 - making it uniquely suited for 5 V industrial systems requiring comprehensive supervision without external components.

Availability

STM706AM6F is available at Aetrix Electronics and suitable for industrial PLC controllers, embedded motor drives, medical diagnostic modules, and smart energy meters requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for STM706AM6F 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 STM70x series targets robust system-level supervision in harsh environments, delivering precision reset, watchdog, and power-fail functions in compact packages for space-constrained embedded designs.

FAQ

What is the function of the WDI and WDO pins on STM706AM6F?

WDI (Watchdog Input) is an edge-sensitive pin that resets the internal 1.6 s watchdog timer on each rising or falling transition; if no edge occurs within timeout, WDO (Watchdog Output) goes low. WDO is a push-pull output that can be connected to MR to generate automatic reset on timeout - enabling hardware-based recovery from MCU lockup without firmware intervention.

Can STM706AM6F monitor a 3.3 V supply?

No - STM706AM6F is specified only for 5 V operation (4.5–5.5 V range) with a fixed reset threshold of 4.25–4.50 V. Its internal reference and comparator are calibrated for 5 V rails; using it on 3.3 V will prevent proper reset assertion and may damage the device due to under-voltage operation outside specification.

How does the power-fail comparator (PFI/PFO) differ from the main V_CC reset function?

The PFI input compares against a dedicated 1.25 V reference (independent of the 4.25–4.50 V V_RST threshold), allowing early warning of supply decay before V_CC reaches reset level. When PFI voltage drops below 1.25 V - e.g., via external divider from unregulated input - PFO asserts low, enabling proactive system response such as data save or graceful shutdown.

Is STM706AM6F pin-compatible with other STM70x devices?

Yes - STM706AM6F shares identical TSSOP-8 pinout and footprint with STM705, STM707, STM708, and STM813L variants. However, functional differences exist: STM706 includes both RST and RST outputs and watchdog (WDI/WDO), while STM707/708 omit watchdog, and STM813L has active-high-only RST. Pin compatibility enables layout reuse but requires firmware and schematic validation.