STMicroelectronics STM706PDS6E

Overview

STM706PDS6E from STMicroelectronics is a 3 V precision voltage supervisor IC with active-high reset output (RST), 2.59–2.70 V reset threshold, 200 ms reset timeout (trec), 1.6 s watchdog timer, and integrated power-fail comparator (PFI/PFO). It monitors VCC in microprocessor-based systems to ensure reliable power-on reset and brownout protection in industrial controllers and embedded instrumentation.

For engineers reviewing the STM706PDS6E datasheet, STM706PDS6E pinout, STM706PDS6E application, or STM706PDS6E equivalent, key selection criteria include reset polarity (active-high), guaranteed RST assertion down to VCC = 1.0 V, push-pull RST/RST/WDO/PFO outputs, low 40 µA supply current, and compatibility with SO8 and TSSOP8 footprints.

Technical Context

The STM706PDS6E implements a precision bandgap reference and dual comparators: one for VCC monitoring (VRST = 2.59–2.70 V) and another for independent power-fail detection (VPFI ≈ 1.25 V). Its reset logic guarantees RST remains high for VCC ≥ VRST and asserts high for trec after VCC rises above VRST or MR de-asserts.

It integrates a 1.6 s watchdog timer cleared by WDI edges (≥50 ns), with WDO asserted on timeout - usable as a reset source when wired to MR. All digital I/Os (MR, WDI, WDO, RST, RST, PFO) are push-pull; PFI is high-impedance input with internal biasing.

Key Specifications

Pinout & Package

STM706PDS6E is housed in an 8-pin TSSOP package (3 mm × 3 mm, DS suffix), pin-compatible with SO8 but offering reduced board area and improved thermal performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM706RDS6E, STM706PDS6E provides active-high reset for direct MCU compatibility without inverters; versus TPS3808G125DBVR, it delivers integrated watchdog and early power-fail signaling - critical for fail-safe embedded systems requiring layered supervision.

Availability

STM706PDS6E is available at Aetrix Electronics and suitable for industrial PLC controllers, medical diagnostic instruments, smart energy meters, and automotive body control modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for STM706PDS6E 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 devices for industrial, automotive, and consumer markets.

The STM70x supervisor family targets robust, low-power microprocessor supervision in space-constrained industrial and instrumentation applications, emphasizing precision thresholds, guaranteed reset behavior, and integrated fault-detection features.

FAQ

What is the function of the PFI and PFO pins on STM706PDS6E?

PFI is a high-impedance analog input compared against an internal 1.25 V reference (VPFI); when PFI voltage drops below VPFI, PFO - a push-pull output - goes low. This enables early detection of power supply degradation before VCC falls below the reset threshold, allowing time for controlled shutdown or data preservation.

Can the watchdog timer be disabled on STM706PDS6E?

Yes - the watchdog timer is disabled when the WDI pin is left floating or tri-stated. The device requires ≤10 µA leakage and ≤200 pF load capacitance on WDI in this state. No configuration register or external component is needed; disabling occurs inherently due to lack of edge transitions.

How does STM706PDS6E ensure reset validity down to VCC = 1.0 V?

The internal reset generator maintains RST high for VCC ≥ VRST and guarantees RST remains high down to VCC = 1.0 V (at TA = 0–85 °C). Below 1.0 V, RST becomes high-impedance; a 100 kΩ pulldown resistor on the RST pin ensures safe low state during deep brownout, per Figure 10 in the datasheet.

Is STM706PDS6E pin-compatible with other STM706 variants?

Yes - STM706PDS6E uses the TSSOP8 (DS) package and shares identical pinout with STM706TDS6E, STM706SDS6E, STM706RDS6E, and STM708 variants. Only RST/RST polarity and V_RST thresholds differ; all share MR, WDI, WDO, PFI, PFO, VCC, and VSS connections in the same physical layout.