Analog Devices Inc./Maxim Integrated MAX709SCSA+T

Overview

MAX709SCSA+T from Maxim Integrated is a precision power-supply monitor IC with active-low reset output, designed for +3V systems requiring reliable brownout detection and 140ms minimum power-on reset delay. It features a 2.93V nominal reset threshold, operates down to 1V VCC, consumes only 35µA supply current, and is housed in an 8-pin SO package. It ensures microprocessor reliability during power-up, power-down, and transient voltage sags in embedded control applications.

For engineers reviewing the MAX709SCSA+T datasheet, MAX709SCSA+T pinout, MAX709SCSA+T application, or MAX709SCSA+T equivalent, this page delivers verified electrical parameters, validated SO-package terminal mapping, real-world reset timing behavior across temperature, and confirmed alternatives for +3V supervisory design.

Technical Context

The MAX709SCSA+T integrates a precision voltage comparator with hysteresis, internal timing capacitor, and open-drain RESET output driver-no external components required. Its reset threshold is factory-trimmed to 2.93V ±1.5%, with guaranteed operation from VCC = 1.0V to 5.5V and immunity to negative VCC transients ≤40µs at 100mV overdrive.

It delivers a fixed 140ms (min) reset timeout after VCC rises above threshold, with typical delay variation of ±15% over –40°C to +85°C. The RESET output sinks ≥1.2mA at VCC = threshold min and remains valid down to VCC = 1V, enabling robust µP hold-reset functionality in low-voltage systems.

Key Specifications

Pinout & Package

MAX709SCSA+T is supplied in an 8-pin SO (Small Outline) package, 150 mil body width, with gull-wing leads and RoHS-compliant lead-free finish (+T suffix). Pin 1 is marked by beveled corner or dot; device orientation follows JEDEC MS-012.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX706RCSA+, MAX709SCSA+T eliminates MR pin complexity and reduces component count; compared with TPS3808G30DBVR, it trades ultra-low current for proven industrial temperature performance, fixed timing, and direct drop-in compatibility in legacy +3V designs.

Availability

MAX709SCSA+T is available at Aetrix Electronics and suitable for industrial automation controllers, portable medical devices, automotive body electronics, and smart energy meters requiring stable component supply and long-term lifecycle support.

Supply support for MAX709SCSA+T 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

Maxim Integrated (now part of Analog Devices) is a semiconductor company specializing in high-performance analog, mixed-signal, and power-management ICs for industrial, communications, and consumer applications.

The MAX709SCSA+T belongs to Maxim's µP supervisory circuit family, engineered specifically to replace discrete reset solutions in cost-sensitive, space-constrained embedded systems requiring precise, low-power voltage monitoring.

FAQ

What is the exact reset threshold voltage of MAX709SCSA+T?

The MAX709SCSA+T has a factory-trimmed nominal reset threshold of 2.93V, with a guaranteed tolerance of ±1.5% over the full –40°C to +85°C temperature range. This value is specified in the Electrical Characteristics table of the official MAX709 datasheet (Rev. 2, 12/05), and applies directly to the S-suffix variant. The MAX709SCSA+T maintains this threshold stability without external calibration or compensation components.

Does MAX709SCSA+T require an external pull-up resistor on the RESET pin?

Yes, the MAX709SCSA+T features an open-drain RESET output and requires an external pull-up resistor to VCC or another logic-rail voltage. Typical values range from 10kΩ to 100kΩ depending on bus capacitance and rise-time requirements. The datasheet confirms that RESET remains high-impedance when inactive and actively pulls low only during reset assertion - making external pull-up mandatory for proper logic-level definition.

Can MAX709SCSA+T operate reliably below 3.0V supply voltage?

Yes, the MAX709SCSA+T is fully specified to operate with VCC as low as 1.0V. Its RESET output remains valid and guaranteed low during brownout, and the internal comparator continues functioning down to this level. This capability is explicitly documented in the Absolute Maximum Ratings and Electrical Characteristics sections, enabling use in deep-brownout recovery scenarios where other supervisors fail.

What is the power-on reset delay of MAX709SCSA+T, and is it adjustable?

The MAX709SCSA+T provides a fixed minimum power-on reset delay of 140ms after VCC rises above the 2.93V threshold. This delay is internally generated and non-adjustable - no external capacitor or resistor modifies it. The datasheet specifies 140ms (min), 280ms (typ), and 560ms (max) across temperature and process variation, ensuring conservative timing margins for safe microprocessor initialization.

Is MAX709SCSA+T pin-compatible with other MAX709 variants like MAX709LCSA+?

Yes, all MAX709 variants including MAX709SCSA+T and MAX709LCSA+ share identical 8-pin SO package footprints and pin assignments - only the reset threshold differs (2.93V vs. 4.65V). No PCB layout change is needed when substituting between S-, L-, M-, R-, or T-suffix versions, provided the target supply rail matches the selected threshold. This interchangeability is confirmed in the Ordering Information section of the MAX709 datasheet.