Analog Devices Inc./Maxim Integrated MAX814KCPA+

Overview

MAX814KCPA+ from Maxim Integrated is a high-accuracy, low-power microprocessor supervisory circuit providing power-on reset, manual reset, and early power-fail warning functions for +5V systems. It features a 4.80V ±1% reset threshold, 200ms reset pulse width, active-low RESET output, and guaranteed valid reset assertion down to VCC = 1V. It is used in medical equipment and portable battery-powered devices requiring reliable µP power monitoring.

For engineers reviewing the MAX814KCPA+ datasheet, MAX814KCPA+ pinout, MAX814KCPA+ application, or MAX814KCPA+ equivalent, this page delivers verified functional specifications, package mapping, real-world use scenarios, and validated alternative options - all specific to the MAX814KCPA+ variant with K-suffix (4.80V), commercial temperature range (0°C to +70°C), and 8-pin PDIP package.

Technical Context

The MAX814KCPA+ implements a precision reset comparator with ±1% worst-case threshold accuracy referenced to a factory-trimmed internal bandgap, immune to fast VCC transients up to 30µs at 100mV overdrive. Its low-line detector asserts LOW LINE when VCC falls 60mV above the 4.80V reset threshold, enabling early brownout warning before system reset.

It integrates a manual-reset input (MR) with 150µA internal pull-up, power-fail comparator (PFI/PFO) with 2.50V reference, and dual-output reset logic (active-low RESET and active-high RESET). No watchdog or adjustable threshold functionality - those are exclusive to MAX815 and MAX816 variants.

Key Specifications

Pinout & Package

MAX814KCPA+ is supplied in an 8-pin plastic DIP (PDIP) package, 0.3-inch body width, through-hole mountable. Pin 1 is marked with a notch or dot; pin numbering is counterclockwise from the notch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX814KCPA+, MAX814KCSA+ offers identical supervision performance in SO packaging for volume SMT production, while TPS3808G18DBVR serves lower-voltage domains with reduced feature set but lower quiescent current - neither is a drop-in replacement for 5V, dual-output, low-line-aware applications.

Availability

MAX814KCPA+ is available at Aetrix Electronics and suitable for medical equipment, industrial controllers, portable instrumentation, and consumer set-top boxes requiring stable component supply and long-term manufacturability.

Supply support for MAX814KCPA+ 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.

The MAX814 family targets high-reliability microprocessor supervision in 5V systems, emphasizing ±1% reset accuracy, low power, and integrated early-warning capability - specifically optimized for applications where deterministic power-up, brownout response, and field-service manual reset are critical.

FAQ

What is the exact reset threshold voltage of the MAX814KCPA+?

The MAX814KCPA+ has a factory-trimmed reset threshold of 4.80V with ±1% worst-case accuracy across temperature and supply variations. This value is fixed by the 'K' suffix and applies to all units. The threshold is referenced to an internal bandgap and does not require external components. At 25°C, typical VRT is 4.83V, with min/max limits of 4.75V and 4.85V respectively per datasheet Electrical Characteristics table.

Does the MAX814KCPA+ include a watchdog timer function?

No, the MAX814KCPA+ does not include a watchdog timer. Watchdog functionality is exclusive to the MAX815 variant (e.g., MAX815KCPA+). The MAX814KCPA+ provides only power-on reset, manual reset, power-fail monitoring (PFI/PFO), and low-line detection (LOW LINE). Its pinout lacks WDI and WDO terminals, and its block diagram confirms absence of watchdog circuitry.

Can the MAX814KCPA+ monitor a voltage other than VCC?

Yes, the MAX814KCPA+ can monitor auxiliary voltages using the PFI input. Connect a resistive divider from the target voltage to PFI, sized so the divided voltage crosses 2.50V (the PFI reference) at the desired trip point. For example, to monitor a +12V rail for failure at ~11V, use a 340kΩ/100kΩ divider. PFO then asserts low to signal degradation, and can be connected to MR to trigger a system reset if needed.

What is the purpose of the LOW LINE output on the MAX814KCPA+?

The LOW LINE output on the MAX814KCPA+ is an active-low signal that asserts when VCC falls to 60mV above the 4.80V reset threshold (~4.86V). It provides early brownout warning before final reset, enabling the µP to execute critical housekeeping tasks - such as saving volatile data or disabling peripherals - during the 60mV window before RESET is asserted. It is electrically identical to RESET but triggered earlier.

Is the MAX814KCPA+ compatible with 3.3V microprocessors?

The MAX814KCPA+ is designed for +5V systems and has a fixed 4.80V reset threshold, making it unsuitable for direct supervision of 3.3V µPs, which typically require reset thresholds near 3.0V–3.1V. For 3.3V applications, use the MAX814T variant (3.03V threshold) or MAX816 with adjustable threshold. Using MAX814KCPA+ with a 3.3V µP would assert reset continuously, as VCC never reaches 4.80V.