STMicroelectronics TL7702ACP/A

Overview

TL7702ACP/A from STMicroelectronics is a precision supply voltage supervisor IC designed for power-on and brown-out reset generation in microcontroller-based systems. It features a 2.5 V threshold voltage (±30 mV), true/complement reset outputs (RESET high-active, RESET̅ low-active), externally adjustable reset pulse width via capacitor on CT pin, and operates across 3.6 V to 18 V supply range with ±15 mV hysteresis at the SENSE input.

For engineers reviewing the TL7702ACP/A datasheet, TL7702ACP/A pinout, TL7702ACP/A application, or TL7702ACP/A equivalent, key selection considerations include its fixed 2.5 V sensing threshold, temperature-compensated reference (2.53 V typ.), CT-timed reset delay (1.3×10⁴ × Cₜ seconds), SO-8 package compatibility, and dual-output reset signaling for robust microprocessor initialization.

Technical Context

The TL7702ACP/A implements a precision bandgap-based voltage reference and comparator architecture with built-in hysteresis (±15 mV) to prevent chatter during supply voltage transitions. Its SENSE input monitors V_CC directly, triggering reset when voltage falls below 2.45–2.58 V (25 °C) or rises above VT+ after power-up.

Reset timing is fully controlled by an external capacitor on the CT pin (Pin 3), enabling user-defined pulse widths from sub-millisecond to seconds; the REF output (Pin 1) requires a 0.1 µF bypass capacitor to suppress fast transients and stabilize the internal reference.

Key Specifications

Pinout & Package

TL7702ACP/A is housed in an 8-pin SOIC (SO-8) surface-mount package with standard 1.27 mm pitch, 5.0 mm × 6.2 mm body, and JEDEC MS-012AC outline. Thermal resistance is 120 °C/W (junction-to-ambient).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3808G12DBVR and MAX691CPA+, TL7702ACP/A uniquely supports wide-input voltage (3.6–18 V), field-adjustable reset timing, and simultaneous true/complement outputs-making it optimal for flexible 3.3 V microcontroller supervision where timing and interface compatibility are critical.

Availability

TL7702ACP/A is available at Aetrix Electronics and suitable for industrial PLC controllers, automotive body control modules, and smart energy meters requiring stable component supply and long-lifecycle support.

Supply support for TL7702ACP/A 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, delivering silicon solutions for automotive, industrial, and consumer markets since 1987.

The TL7700A series belongs to ST's analog power-supervision product line, engineered specifically for deterministic reset generation in microprocessor and microcontroller systems where supply integrity is mission-critical.

FAQ

What is the function of the CT pin on TL7702ACP/A?

The CT pin (Pin 3) connects to an external capacitor that sets the reset pulse width via t_po = 1.3 × 10⁴ × C_T (seconds). With a 0.1 µF capacitor, the typical delay is 1.3 ms-sufficient for most 8-bit and 16-bit microcontrollers to complete internal initialization before releasing reset.

Can TL7702ACP/A monitor a 5 V supply directly?

Yes. The TL7702ACP/A senses at 2.5 V, so it must be used with a resistive divider to scale a 5 V rail down to 2.5 V at the SENSE pin. However, note that the device's absolute maximum SENSE voltage is limited to V_S − 1 V or 6 V (whichever is lower), making direct 5 V monitoring unsafe without scaling.

How does the REF pin improve system reliability?

The REF pin provides a buffered 2.53 V reference output. When decoupled with a 0.1 µF capacitor to GND, it suppresses high-frequency noise on the internal reference node-reducing false triggers caused by supply transients and ensuring consistent threshold detection across temperature and load conditions.

Is TL7702ACP/A pin-compatible with other TL7700A variants?

No. While all TL7700A-series devices share the same SO-8 pinout, the TL7702ACP/A has a fixed 2.5 V threshold and no external resistor network. Other variants (e.g., TL7705A) require R1/R2 dividers on SENSE to set different thresholds, meaning PCB layout and BOM differ even though physical pin mapping matches.