Analog Devices Inc. ADM709SANZ

Overview

ADM709SANZ from Analog Devices is a precision power supply monitor IC with active-low reset output, 2.93 V threshold, 140 ms minimum power-on reset pulse, and operation down to 1 V supply voltage; used for reliable microprocessor reset in industrial embedded systems during power-up, brownout, and power-down events.

For engineers reviewing the ADM709SANZ datasheet, ADM709SANZ pinout, ADM709SANZ application, or ADM709SANZ equivalent, key selection considerations include reset threshold accuracy (±70 mV), guaranteed RESET assertion at VCC ≥ 1 V, 35 µA quiescent current, and compatibility with +3 V supply rails in space-constrained DIP-8 layouts.

Technical Context

The ADM709SANZ implements a bandgap-based voltage comparator with internal timing circuitry to generate a minimum 140 ms active-low reset pulse after VCC rises above 2.93 V. It features glitch immunity against short VCC transients and maintains RESET low during brownout until VCC drops below threshold.

RESET remains functional with VCC as low as 1 V, enabling stable shutdown sequencing; no external components are required for basic operation, though a 100 kΩ pull-down resistor ensures valid logic low below 1 V per design guidance.

Key Specifications

Pinout & Package

ADM709SANZ is housed in an 8-pin plastic DIP (N-8) package with 0.3" width, lead pitch of 0.1" (2.54 mm), and standard through-hole footprint. Pins 1, 4, 5, 6, and 8 are internally unconnected (NC); only VCC (Pin 2), GND (Pin 3), and RESET (Pin 7) are functional.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar power supply monitor applications.

Compared with MAX709SAP+ and TPS3808G30DBVR, ADM709SANZ uniquely combines guaranteed 1 V operation, factory-trimmed 2.93 V threshold, and self-timed 140 ms reset without external capacitors - making it optimal for cost-sensitive, space-constrained industrial designs requiring robust low-voltage reset assurance.

Availability

ADM709SANZ 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 across extended temperature ranges and long production lifecycles.

Supply support for ADM709SANZ 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

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA.

The ADM709 family was designed specifically as low-cost, precision voltage supervisors for microprocessor reset in industrial and embedded systems - emphasizing threshold accuracy, low IQ, and guaranteed operation across full VCC range.

FAQ

What is the exact reset threshold voltage for ADM709SANZ?

The ADM709SANZ has a factory-trimmed reset threshold of 2.93 V, with a tolerance of ±70 mV (2.85 V to 3.00 V) over the full –40°C to +85°C operating range. This value is specified in Table I of the official Analog Devices datasheet and applies exclusively to the 'S' suffix variant, including ADM709SANZ.

Does ADM709SANZ require external components to function?

No, ADM709SANZ operates autonomously with only VCC and GND connections. Its 140 ms power-on reset pulse is internally generated. A 100 kΩ pull-down resistor on RESET is optional and recommended only if valid logic low must be maintained below 1 V VCC, per Figure 5 in the datasheet.

Can ADM709SANZ drive a microcontroller reset pin directly?

Yes, ADM709SANZ RESET output can directly drive most microcontroller reset inputs. It sinks up to 1.2 mA while asserted low (≤0.3 V), meeting TTL/CMOS input requirements. For bidirectional reset lines (e.g., MC68HC11), a 4.7 kΩ series resistor is advised to prevent contention, as shown in Figure 6.

What is the minimum supply voltage at which ADM709SANZ guarantees RESET functionality?

ADM709SANZ guarantees RESET output functionality down to 1.0 V VCC, as explicitly stated in the General Description and confirmed in the "RESET at Voltages < 1 V" section. Below 1 V, a 100 kΩ pull-down ensures valid low state, but internal timing and comparator operation are not assured.

Is ADM709SANZ pin-compatible with other ADM709 variants?

Yes, all ADM709 variants-including ADM709SANZ-share identical 8-pin N-8 (DIP) pinout and terminal functions. The only differences are reset threshold voltage and ordering suffix; VCC (Pin 2), GND (Pin 3), and RESET (Pin 7) retain identical roles across the family.