Analog Devices Inc./Maxim Integrated MAX699CPA

Overview

The MAX699CPA from Maxim Integrated is an 8-pin PDIP power-on reset and watchdog controller for +5V microprocessor systems. It delivers a guaranteed 140ms RESET pulse on power-up, brownout (trip at 4.4V), and power-down, includes a 1-second watchdog timeout with WDI input, and operates from 3.0V to 5.5V supply voltage - used in embedded controllers requiring reliable power sequencing and processor supervision.

For engineers reviewing the MAX699CPA datasheet, MAX699CPA pinout, MAX699CPA application, or MAX699CPA equivalent, key selection criteria include its fixed 4.65V reset threshold with 40mV hysteresis, open-drain RESET output (0.4V @ 1.6mA), watchdog disable-by-open-WDI feature, and C-grade (0°C to +70°C) industrial temperature rating.

Technical Context

The MAX699CPA integrates a precision voltage monitor and monostable reset timer with internal hysteresis to prevent chatter during supply ramping. Its watchdog circuit monitors WDI transitions and forces RESET low if no toggle occurs within 1 second - a function disabled when WDI is left floating.

This device uses internal bandgap reference and comparator architecture to assert RESET below 4.4V and deassert above 4.65V, delivering deterministic timing without external RC components. The open-drain RESET output supports wired-OR configurations and pull-up to any logic rail up to VCC.

Key Specifications

Pinout & Package

MAX699CPA is supplied in an 8-lead plastic dual-inline package (PDIP), pin-compatible with industry-standard DIP-8 footprints and compatible with through-hole assembly processes.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar power-on reset and watchdog applications.

Compared with MAX698CPA and TPS3808G12DBVR, the MAX699CPA uniquely offers watchdog-ready architecture in PDIP form - though WDI is absent on this variant, it shares die-level compatibility with SO versions enabling seamless upgrade paths to supervised operation.

Availability

MAX699CPA is available at Aetrix Electronics and suitable for computers, controllers, intelligent instruments, and critical μP power monitoring applications requiring stable component supply across industrial temperature ranges and long-lifecycle production programs.

Supply support for MAX699CPA 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 industrial, communications, and computing markets.

The MAX698/MAX699 product line delivers low-cost, single-chip power-on reset and watchdog solutions targeting cost-sensitive microprocessor-based systems where reliability and minimal external components are essential.

FAQ

What is the reset threshold voltage of the MAX699CPA?

The MAX699CPA asserts RESET when VCC falls below 4.4V and deasserts when VCC rises above 4.65V, with 40mV hysteresis. This fixed threshold is internally trimmed and does not require external components. The MAX699CPA maintains this behavior across its full 0°C to +70°C operating range, ensuring consistent power-on sequencing in commercial and industrial environments.

Does the MAX699CPA include a functional watchdog timer?

No - the MAX699CPA in 8-pin PDIP package does not implement the watchdog function. While the MAX699 family includes watchdog capability, the WDI input is physically absent on the CPA variant. Watchdog operation is only available on 16-pin SO packages (e.g., MAX699CWE). The MAX699CPA provides identical reset functionality to the MAX698CPA but belongs to the MAX699 die family for future upgradeability.

What is the minimum RESET pulse width guaranteed by the MAX699CPA?

The MAX699CPA guarantees a minimum RESET pulse width of 140ms, with typical duration up to 500ms depending on supply ramp rate and temperature. This timing is fully internal and independent of external components, satisfying standard microprocessor reset timing requirements such as those for Intel 80x86 and ARM Cortex-M series devices during power-up and brownout events.

Can the MAX699CPA drive a standard TTL input directly?

Yes - the MAX699CPA's open-drain RESET output sinks up to 1.6mA at 0.4V maximum when pulled low, meeting TTL input low-level voltage and current requirements. A pull-up resistor to the target logic rail (e.g., +5V or +3.3V) is required. The MAX699CPA supports direct interfacing with TTL, CMOS, and microcontroller reset inputs without level-shifting circuitry.

Is the MAX699CPA RoHS-compliant?

Yes - the MAX699CPA is available in both leaded and lead(Pb)-free packaging. To order the RoHS-compliant version, append the "+" symbol to the part number (i.e., MAX699CPA+). The device meets JEDEC J-STD-020 moisture sensitivity level 1 and is qualified for reflow soldering per IPC/JEDEC J-STD-020 standards.