Analog Devices Inc./Maxim Integrated MAX814KCSA+T

Overview

MAX814KCSA+T from Maxim Integrated is a ±1% accurate, low-power microprocessor supervisory circuit with fixed 4.80V reset threshold, active-low RESET output, manual reset input (MR), power-fail monitor (PFI/PFO), and low-line detection. It guarantees valid RESET down to VCC = 1V and delivers 200ms reset pulse width-designed for reliable power-on reset and brownout protection in +5V embedded controllers and medical instrumentation.

For engineers reviewing the MAX814KCSA+T datasheet, MAX814KCSA+T pinout, MAX814KCSA+T application, or MAX814KCSA+T equivalent, key selection criteria include reset threshold accuracy (±1%), supply current (75µA max), guaranteed operation down to 1V VCC, immunity to fast VCC transients, and compatibility with 8-pin SO package layouts in space-constrained portable systems.

Technical Context

The MAX814KCSA+T implements a precision voltage comparator with 4.80V ±1% trip point referenced to internal bandgap, coupled with a 200ms monostable timer that holds RESET low after threshold crossing. Its low-line detector triggers 60mV above the reset threshold (i.e., 4.86V) with 2mV hysteresis, enabling early warning before full reset assertion.

It integrates independent power-fail monitoring via PFI (2.50V threshold) and PFO open-drain output, while MR accepts CMOS/TTL logic with internal 150µA pull-up-allowing direct switch-to-GND connection without external components. All functions operate across 0°C to +70°C with no external trimming required.

Key Specifications

Pinout & Package

MAX814KCSA+T is housed in an 8-pin SO (Small Outline) package, surface-mount compatible with JEDEC MS-012AC footprint, 3.9mm × 4.9mm body size, 1.27mm lead pitch, and gull-wing leads. Thermal performance supports continuous operation at up to +70°C ambient.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor supervisory applications.

Compared with MAX814KCSA+T, MAX809SEUR+T reduces feature set to minimize cost and footprint but eliminates critical diagnostics like early power-fail warning; TPS3808G33DBVR adds flexibility in timing but increases quiescent current and removes the low-line detector essential for predictive shutdown in portable systems.

Availability

MAX814KCSA+T is available at Aetrix Electronics and suitable for medical infusion pumps, industrial PLC controllers, portable diagnostic handhelds, and set-top box power management requiring stable component supply across extended production lifecycles.

Supply support for MAX814KCSA+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) designs precision analog and mixed-signal ICs for demanding industrial, medical, and communications applications-with emphasis on reliability, accuracy, and low-power operation.

The MAX814 family targets microprocessor supervisory needs in safety-critical and battery-sensitive systems, delivering ±1% reset accuracy, glitch immunity, and multi-function integration (reset, watchdog, power-fail, low-line) in minimal footprint.

FAQ

What is the exact reset threshold voltage of the MAX814KCSA+T?

The MAX814KCSA+T has a factory-trimmed reset threshold of 4.80V with ±1% worst-case accuracy across temperature, voltage, and process variation. This value is confirmed in the Electrical Characteristics table for +5V parts (MAX814K/MAX815K) and applies specifically to the 'K' suffix variant. The threshold remains stable from 0°C to +70°C with typical deviation under ±2mV.

Does the MAX814KCSA+T support both active-low and active-high reset outputs?

Yes, the MAX814KCSA+T provides dual reset outputs: pin 7 is active-low RESET, and pin 8 is its active-high complement. Both outputs are push-pull and electrically isolated-enabling direct interface with µPs requiring either polarity without external inverters. This dual-output architecture is unique to the MAX814 and MAX816 variants within the family.

Can the MAX814KCSA+T monitor voltages other than VCC?

Yes-the MAX814KCSA+T supports auxiliary voltage monitoring via the PFI pin, which compares an external voltage against a fixed 2.50V internal reference. By connecting a resistor divider from a +12V rail to PFI, the device can assert PFO to warn of impending failure before the main +5V rail drops. This capability is documented in Figure 11 and Applications Information section.

What is the purpose of the LOW LINE output on the MAX814KCSA+T?

The LOW LINE output on the MAX814KCSA+T is an active-low open-drain signal that asserts when VCC falls to 60mV above the 4.80V reset threshold (i.e., at 4.86V). It provides early warning-typically 10–50ms before full reset-allowing firmware to execute critical save routines. Unlike RESET, LOW LINE has no minimum pulse width, making it ideal for NMI-triggered interrupt handling.

Is the MAX814KCSA+T compatible with lead-free soldering processes?

Yes, the MAX814KCSA+T is supplied in lead-free packaging, as indicated by the '+' symbol in the part number suffix. It complies with JEDEC J-STD-020 moisture sensitivity level (MSL) 1 and supports standard reflow profiles up to 260°C peak temperature. The SO package uses matte tin terminations suitable for Pb-free assembly without risk of whisker formation.