Analog Devices Inc./Maxim Integrated MAX709LCSA-TG068

Overview

MAX709LCSA-TG068 from Maxim Integrated is a precision power-supply monitor IC with active-low reset output, designed for +5V systems requiring 4.65V reset threshold, 140ms minimum reset timeout, and operation down to VCC = 1V. It eliminates external components in microprocessor supervisory circuits and supports SO-8 packaging for compact board layout in industrial control and embedded instrumentation.

For engineers reviewing the MAX709LCSA-TG068 datasheet, MAX709LCSA-TG068 pinout, MAX709LCSA-TG068 application, or MAX709LCSA-TG068 equivalent, key selection criteria include reset threshold tolerance (±0.15V), supply current (65µA typical), temperature stability of threshold (±0.5% over –40°C to +85°C), and immunity to sub-40µs negative VCC transients.

Technical Context

The MAX709LCSA-TG068 integrates a precision voltage comparator with hysteresis, internal timing capacitor, and open-drain RESET driver. Its reset assertion is triggered when VCC falls below 4.65V nominal, with guaranteed release after VCC rises above 4.75V (max) and holds low for ≥140ms during power-up.

It operates across –40°C to +85°C with no external components required, delivers 20mA sink capability on RESET, and maintains valid output state down to VCC = 1V - enabling reliable µP reset sequencing even during deep brownout conditions.

Key Specifications

Pinout & Package

MAX709LCSA-TG068 is supplied in an 8-pin SO (Small Outline) package, 150mil body width, with gull-wing leads and RoHS-compliant finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX706RCSA+, MAX709LCSA-TG068 provides identical reset accuracy and timing but omits manual reset and watchdog - reducing component count and cost in fixed-function supervision roles. Against TPS3808G33DBVR, it trades ultra-low current for higher threshold precision and industrial temperature support.

Availability

MAX709LCSA-TG068 is available at Aetrix Electronics and suitable for industrial automation, medical diagnostics, automotive body electronics, and smart metering applications requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for MAX709LCSA-TG068 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 fabless semiconductor company specializing in high-performance analog, mixed-signal, and power-management ICs for industrial, communications, and computing markets.

The MAX709 family was engineered specifically for cost-sensitive, space-constrained microprocessor supervision - delivering precision reset thresholds, guaranteed timeout, and robust transient immunity without external passive components.

FAQ

What is the exact reset threshold voltage for MAX709LCSA-TG068?

The MAX709LCSA-TG068 has a nominal reset threshold of 4.65V, with a guaranteed range of 4.50V (min) to 4.75V (max) across –40°C to +85°C. This threshold is factory-trimmed and does not require external calibration. The 'L' suffix in MAX709LCSA-TG068 explicitly denotes the 4.65V version, confirmed in Maxim's official ordering guide and electrical characteristics table.

Does MAX709LCSA-TG068 require external components to function?

No, MAX709LCSA-TG068 operates autonomously with no external resistors, capacitors, or trimming components. A 0.1µF ceramic bypass capacitor on VCC (pin 2) is recommended for transient immunity but is not required for basic reset functionality. The internal timing capacitor and precision voltage reference eliminate all external dependencies, directly supporting its "minimum component count" design goal.

What is the maximum allowable negative VCC transient duration that will not trigger reset on MAX709LCSA-TG068?

Per Maxim's Typical Operating Characteristics, MAX709LCSA-TG068 tolerates negative VCC transients ≤40µs in duration when the transient magnitude is ≤100mV below the 4.65V threshold. This immunity is inherent to the comparator architecture and does not require external filtering. Transients exceeding this limit - such as those from relay switching or motor commutation - will assert RESET as intended.

Can MAX709LCSA-TG068 drive a microprocessor reset pin directly?

Yes, MAX709LCSA-TG068 can drive most µP reset pins directly via its open-drain RESET output (pin 7), provided an external pull-up resistor (typically 10kΩ to VCC) is used. It sinks up to 20mA, exceeding the input leakage and capacitance requirements of common processors like STM32, PIC, and Renesas RX series. No buffer stage is needed unless driving multiple loads or long traces.

Is MAX709LCSA-TG068 compatible with 3.3V systems?

No, MAX709LCSA-TG068 is specified for 4.65V threshold and optimized for +5V systems. While it operates with VCC as low as 1.0V, its reset assertion occurs only when VCC drops below ~4.5V - making it unsuitable for primary supervision of 3.3V rails. For 3.3V systems, use MAX709TCSA+ (3.08V threshold) or MAX706SCSA+ (2.93V), both in the same SO-8 package.