STMicroelectronics STM706RDAM6F

Overview

STM706RDAM6F from STMicroelectronics is a precision 3 V supply voltage supervisor IC with active-high reset output (RST), watchdog timer, manual reset input (MR), and power-fail comparator (PFI/PFO). It asserts reset for VCC < 2.59 V (min) to 2.70 V (max), guarantees RST assertion down to VCC = 1.0 V, and delivers 200 ms typical reset timeout (trec) - used in industrial microcontroller systems requiring reliable power-on and brownout recovery.

For engineers reviewing the STM706RDAM6F datasheet, STM706RDAM6F pinout, STM706RDAM6F application, or STM706RDAM6F equivalent, key selection criteria include reset threshold tolerance (±2.2% over temperature), push-pull RST output drive capability, watchdog timeout stability (±5% over –40 °C to +85 °C), and PFI comparator accuracy (1.25 V ±1.2% at 25 °C).

Technical Context

The STM706RDAM6F integrates a precision bandgap reference, dual independent comparators (VCC monitor and PFI threshold), a 1.6 s watchdog timer with edge-triggered clear, and trec generator with guaranteed timing across temperature. Its RST output remains valid and asserted as long as VCC ≥ 1.0 V, enabling robust reset hold during deep brownout conditions.

It features separate push-pull outputs for RST (active-high) and PFO, both capable of driving TTL/CMOS loads without external pull-ups. The MR input includes an internal 40 kΩ pull-up, supporting direct switch-to-ground connection without debounce circuitry.

Key Specifications

Pinout & Package

STM706RDAM6F is housed in an 8-pin TSSOP package (3 mm × 3 mm, 0.65 mm pitch), RoHS-compliant and lead-free. Pin assignments are validated per STMicroelectronics DocID10518 Rev 14 (Figures 4 & Table 3).

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM706RDAM6F, MAX6361KA29+T offers smaller footprint but omits watchdog and PFI functionality, while TPS3808G12DBVR provides threshold adjustability at the cost of added BOM complexity and missing predictive power-fail signaling.

Availability

STM706RDAM6F is available at Aetrix Electronics and suitable for industrial controllers, medical instruments, smart meters, and automotive body control modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for STM706RDAM6F 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 microcontrollers, power management ICs, sensors, and analog/mixed-signal devices for industrial, automotive, and consumer markets.

The STM70x series is ST's industrial-grade voltage supervisor product line, engineered specifically for deterministic power-on reset, brownout protection, and system-level fault recovery in resource-constrained embedded systems.

FAQ

What is the function of the WDO pin on STM706RDAM6F?

The WDO (Watchdog Output) pin is a push-pull active-low output that asserts when the watchdog timer expires (after 1.6 s of no WDI edge transition). Unlike RST, WDO returns high immediately when VCC rises above the reset threshold - making it suitable for generating interrupt signals or feeding back to MR for watchdog-initiated reset. It does not assert during VCC brownout unless explicitly connected to MR.

Can STM706RDAM6F monitor a 5 V supply?

No - STM706RDAM6F is specified for 3 V operation only, with absolute maximum VCC rating of 6.0 V and guaranteed performance between 2.7 V and 5.5 V. Its internal reset comparator is trimmed for 2.59–2.70 V thresholds, optimized for 3 V systems. Monitoring 5 V rails requires a voltage divider on VCC or use of a higher-threshold supervisor like STM708R.

How does the PFI/PFO function enable predictive power failure handling?

PFI compares an external voltage (e.g., from a resistor divider on an unregulated input rail) against a stable 1.25 V internal reference. When PFI falls below this threshold, PFO asserts low - typically connected to MR to trigger reset *before* VCC drops below the 2.59 V reset threshold. This provides 5–15 ms advance warning depending on supply droop rate, enabling safe data save or state capture.

Is STM706RDAM6F pin-compatible with other STM706 variants?

Yes - all STM706x variants (T/S/R/P) share identical 8-pin TSSOP and SO8 footprints and pinouts. STM706RDAM6F (R-grade, active-high RST, TSSOP8) is mechanically and electrically compatible with STM706SDM6F (S-grade, active-low RST) and STM706TDM6F (T-grade, active-low RST), differing only in reset threshold and polarity - allowing drop-in replacement where threshold and polarity match system requirements.