Analog Devices Inc./Maxim Integrated MAX795TCPA+

Overview

MAX795TCPA+ from Maxim Integrated is an 8-pin microprocessor supervisory circuit designed for 3.0V/3.3V systems, providing precision reset generation (3.00V–3.15V threshold), backup-battery switchover (VBATT > VCC supported), and chip-enable signal gating with ≤7ns propagation delay. It monitors critical power conditions in battery-backed CMOS RAM applications and asserts active-low reset during brownout or manual trigger.

For engineers reviewing the MAX795TCPA+ datasheet, MAX795TCPA+ pinout, MAX795TCPA+ application, or MAX795TCPA+ equivalent, key selection criteria include guaranteed reset assertion down to VCC = 1V, battery-switching hysteresis (15mV typical), low quiescent current (24–35µA in normal mode), and compatibility with lithium backup batteries up to 3.6V.

Technical Context

The MAX795TCPA+ implements a fixed-threshold reset comparator with 10mV typical hysteresis to prevent oscillation during VCC transitions, and integrates a VCC-to-VBATT switchover circuit that automatically connects OUT to BATT when VCC falls below VSW (2.55V–2.70V range for R-suffix, but T-suffix uses 2.55V–2.70V per MAX795R; MAX795T uses 3.00V–3.15V reset, and VSW = VRST – 15mV). Its CE IN-to-CE OUT transmission gate operates with <7ns propagation delay and supports write-cycle completion via 10µs hold time after reset assertion.

Unlike the MAX793/MAX794, the MAX795TCPA+ omits watchdog timer, battery OK output, low-line comparator, and manual reset input - confirmed by pin count (8-pin vs. 16-pin), functional selector guide, and absence of MR, WDI, WDO, LOWLINE, BATT OK, and RESET IN pins in its pin description. It retains only core functions: reset generation, battery switchover, and CE gating.

Key Specifications

Pinout & Package

MAX795TCPA+ is housed in an 8-pin plastic DIP package (0.300" width), with lead-free plating indicated by the '+' suffix. Pin 1 is OUT, pin 2 is VCC, pin 3 is GND, pin 4 is PFI, pin 5 is BATT ON, pin 6 is PFO, pin 7 is CE IN, and pin 8 is CE OUT.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX795TCPA+, MAX795TSA+ offers identical supervision functionality in a compact SO package ideal for density-optimized designs, while MAX793TPE+ adds MR, watchdog, and low-line monitoring at the cost of larger footprint and higher pin count - making it suitable for feature-rich embedded controllers needing layered fault detection.

Availability

MAX795TCPA+ is available at Aetrix Electronics and suitable for industrial data loggers, medical patient monitors, point-of-sale terminals, and smart energy meters requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX795TCPA+ 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, automotive, and computing applications.

The MAX793/MAX794/MAX795 product line delivers integrated microprocessor supervision for 3.0V/3.3V systems, emphasizing reliable power monitoring, battery backup, and memory protection in space- and power-constrained environments.

FAQ

What is the reset threshold voltage range for MAX795TCPA+?

The MAX795TCPA+ has a fixed reset threshold range of 3.00V to 3.15V (VCC falling), optimized for 3.3V ±5% systems. This ensures reset is asserted before VCC drops below 3.0V - the minimum required to maintain µP functionality - and guarantees operation across the full industrial temperature range (0°C to +70°C). The 'T' suffix in MAX795TCPA+ explicitly denotes this threshold range.

Does MAX795TCPA+ support watchdog timer functionality?

No, MAX795TCPA+ does not include a watchdog timer. Unlike the MAX793/MAX794 variants, the MAX795 family omits WDI, WDO, and associated timing circuitry. This is confirmed by its 8-pin package (vs. 16-pin for MAX793/MAX794), absence of watchdog-related pins in the pin description, and explicit functional differentiation in the Selector Guide. MAX795TCPA+ focuses solely on reset generation, battery switchover, and CE gating.

Can MAX795TCPA+ be used with a 3.6V lithium backup battery?

Yes, MAX795TCPA+ fully supports 3.6V lithium backup batteries. Its absolute maximum VBATT rating is +6.0V, and the datasheet explicitly states "backup-battery voltage can exceed VCC" - permitting direct connection of 3.6V cells even when VCC is 3.0V or 3.3V. The internal p-channel MOSFET switch handles switchover with 15mV typical hysteresis, ensuring glitch-free transition without external components.

What is the purpose of the BATT ON pin on MAX795TCPA+?

The BATT ON pin (Pin 5) is an active-high, open-drain output that signals when the device has switched OUT to the backup battery. It goes high when VBATT > VSW and VCC has fallen below the switchover threshold, enabling external circuitry (e.g., PMOS driver enable) to manage higher-current backup loads. In MAX795TCPA+, BATT ON drives the gate of an external PMOS transistor to extend IOUT beyond the 75mA internal limit - a key design feature for systems with large RAM banks.

Is MAX795TCPA+ pin-compatible with other MAX795 variants?

Yes, all MAX795 variants (e.g., MAX795R, MAX795S, MAX795T) share identical 8-pin DIP/SO pinouts and core functionality - differing only in reset threshold voltage range (R = 2.55V–2.70V, S = 2.85V–3.00V, T = 3.00V–3.15V). The MAX795TCPA+ uses the 'T' threshold and '+' lead-free marking, but electrical and mechanical compatibility is maintained across the MAX795 family for drop-in replacement in existing designs.