STMicroelectronics STM707M6E

Overview

STM707M6E from STMicroelectronics is a 5 V precision voltage supervisor IC with dual reset outputs (active-low RST and active-high RST), power-fail comparator (PFI/PFO), manual reset input (MR), and no watchdog timer. It asserts reset down to VCC = 1.0 V, features 4.50–4.75 V reset threshold, 200 ms typical reset timeout (trec), and operates from –40 °C to 85 °C in industrial environments. It is used in microprocessor-based systems requiring reliable power-on and brownout reset control.

For engineers reviewing the STM707M6E datasheet, STM707M6E pinout, STM707M6E application, or STM707M6E equivalent, key selection considerations include its dual-polarity reset outputs, absence of watchdog functionality (distinguishing it from STM705/706), precise 4.625 V nominal reset threshold, PFI/PFO undervoltage warning capability, and TSSOP8 package compatibility with space-constrained embedded designs.

Technical Context

The STM707M6E implements a dual-comparator architecture: one for VCC monitoring (VRST = 4.50–4.75 V) and another for independent power-fail detection (VPFI ≈ 1.25 V). It guarantees RST assertion down to VCC = 1.0 V and supports bidirectional MCU reset I/O via external series resistor.

Unlike STM705/706, it omits watchdog circuitry - no WDI or WDO pins - simplifying supervision where software watchdogs are handled externally. Its MR input includes an internal 40 kΩ pull-up, enabling direct push-button interfacing without external components.

Key Specifications

Pinout & Package

STM707M6E is housed in an 8-pin TSSOP package (3 mm × 3 mm body, 0.65 mm pitch), optimized for high-density PCB layouts. Pin assignments are validated per STMicroelectronics DocID10520 Rev 11, Figure 6 and Table 3.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM707M6E, STM706M6F adds watchdog functionality at the cost of tighter reset threshold and higher complexity, while MAX809SEUR+T sacrifices dual reset, PFI/PFO, and MR for extreme miniaturization and lower unit cost - making STM707M6E optimal for balanced feature-rich 5 V supervision.

Availability

STM707M6E is available at Aetrix Electronics and suitable for industrial PLC controllers, medical diagnostic instruments, automotive body control modules, and smart energy meters requiring stable component supply and long-term manufacturability.

Supply support for STM707M6E 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 family targets robust, low-power microprocessor supervision in space- and reliability-constrained applications, emphasizing precision threshold accuracy, guaranteed low-VCC reset behavior, and integrated power-fail prediction.

FAQ

What is the function of the NC pin on STM707M6E?

Pin 3 is a no-connect (NC) terminal - it is internally unbonded and electrically isolated. It must remain unconnected on the PCB; routing traces or applying solder to this pin may cause mechanical stress or contamination but has no electrical effect. STMicroelectronics specifies NC to maintain package pinout compatibility across the STM70x series.

Can STM707M6E be used with a 3.3 V microcontroller?

STM707M6E is specified for 5 V operation only (VCC = 4.5–5.5 V) and is not rated for 3.3 V supply. Its reset thresholds, internal references, and output drive levels are calibrated for 5 V logic. Using it with a 3.3 V MCU risks incorrect reset assertion and potential damage if RST/RST outputs exceed absolute maximum ratings of the MCU's I/O pins.

How does the power-fail comparator (PFI/PFO) interact with the main reset function?

PFI and PFO operate independently from the VCC monitor - VPFI ≈ 1.25 V is a separate reference. When PFI voltage drops below VPFI (e.g., due to falling unregulated input), PFO goes low but does not directly assert RST/RST. To trigger reset on power-fail, PFO must be externally connected to MR. This decoupling allows flexible system-level response strategies.

Is STM707M6E RoHS compliant and lead-free?

Yes, STM707M6E is RoHS compliant and lead-free per Directive 2011/65/EU. STMicroelectronics confirms compliance in DocID10520 Rev 11, Section 1, and the device carries the "RoHS-compliant" marking per ordering code conventions ('M6E' suffix denotes TSSOP8, lead-free, industrial grade).