Analog Devices Inc./Maxim Integrated MAX795RCSA+T

Overview

MAX795RCSA+T from Maxim Integrated is an 8-pin SO microprocessor supervisory circuit designed for 3.0V systems, providing fixed reset threshold (2.55V–2.70V), backup-battery switchover with VBATT > VCC support, on-board CE signal gating (7ns max propagation delay), and guaranteed reset assertion down to VCC = 1V. It safeguards CMOS RAM in battery-backed embedded controllers during brownout.

For engineers reviewing the MAX795RCSA+T datasheet, MAX795RCSA+T pinout, MAX795RCSA+T application, or MAX795RCSA+T equivalent, key selection criteria include its R-suffix reset threshold range, 8-pin SO package compatibility, battery-switching hysteresis (15mV typical), and absence of watchdog or BATT OK features compared to MAX793/MAX794 variants.

Technical Context

The MAX795RCSA+T implements a precision voltage-monitoring comparator with fixed 2.55V–2.70V reset threshold (VCC falling), enabling reliable power-fail detection in 3.0V ±10% supply systems. Its internal p-channel MOSFET switch enables seamless switchover from VCC to VBATT when VCC drops below VSW (2.52V min), with 15mV typical hysteresis to prevent oscillation.

It integrates chip-enable gating logic that disables CE IN-to-CE OUT path during reset assertion, preserving RAM integrity; CE OUT remains low for 10µs after reset if CE IN was low, ensuring write-cycle completion. Unlike MAX793/MAX794, it omits watchdog timer, BATT OK output, and manual reset input.

Key Specifications

Pinout & Package

MAX795RCSA+T is housed in an 8-pin SO (Small Outline) package, measuring 4.9mm × 6.0mm × 1.75mm, with standard 1.27mm pitch and gull-wing leads. Thermal resistance θ_JA is 190°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX795RCSA+T, the S- and T-suffix variants shift the reset threshold upward to match 3.3V supply tolerances, making them unsuitable for 3.0V systems but offering tighter margins in 3.3V designs-selection depends strictly on nominal VCC and allowable droop before reset.

Availability

MAX795RCSA+T is available at Aetrix Electronics and suitable for industrial data loggers, medical patient monitors, smart utility meters, and portable test instruments requiring stable component supply across extended temperature ranges (–40°C to +85°C).

Supply support for MAX795RCSA+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) is a semiconductor company specializing in analog, mixed-signal, and power-management ICs for industrial, automotive, and computing applications.

The MAX795 family is a series of 8-pin supervisory circuits targeting cost-sensitive, space-constrained 3.0V/3.3V embedded systems requiring reliable power monitoring and battery backup without watchdog complexity.

FAQ

What is the exact reset threshold voltage range for MAX795RCSA+T?

The MAX795RCSA+T has a fixed reset threshold range of 2.55V to 2.70V for VCC falling, as specified in the Electrical Characteristics table. This range is factory-trimmed and applies across the full operating temperature range (–40°C to +85°C). The device guarantees reset assertion before VCC falls below 2.55V and prevents false triggering above 2.70V under normal conditions. This makes MAX795RCSA+T ideal for 3.0V ±10% supply monitoring.

Does MAX795RCSA+T include a watchdog timer or manual reset input?

No, MAX795RCSA+T does not include a watchdog timer or manual reset (MR) input. These features are present only in the MAX793 and MAX794 variants. The MAX795RCSA+T is functionally streamlined to provide core supervision-reset generation, battery switchover, CE gating, and power-fail detection-without added complexity. Engineers selecting MAX795RCSA+T should implement external reset initiation if needed, as MR and WDI/WDO pins are omitted from this 8-pin variant.

How does the battery switchover work in MAX795RCSA+T when VBATT exceeds VCC?

In MAX795RCSA+T, when VBATT exceeds VCC (e.g., 3.6V lithium cell with 3.0V system rail), the internal p-channel MOSFET automatically connects OUT to VBATT once VCC falls below the battery switch threshold (VSW = 2.52V min). The switch includes 15mV typical hysteresis to prevent oscillation near the threshold. OUT remains tied to VBATT until VCC rises above the reset threshold (2.70V max), at which point it reconnects to VCC. This behavior is guaranteed per Absolute Maximum Ratings and Electrical Characteristics.

What is the purpose of the BATT ON pin on MAX795RCSA+T?

The BATT ON pin on MAX795RCSA+T is an open-drain, active-high output that signals when OUT is sourced from VBATT (i.e., battery-backup mode is active). It drives high when VCC falls below VSW and VBATT is present, enabling control of an external PMOS transistor to handle load currents exceeding the 75mA internal switch limit. This allows scalable backup power delivery while maintaining low leakage (<1µA) when inactive-critical for multi-year battery life in portable equipment.

Can MAX795RCSA+T be used with a 5V main supply?

Yes, MAX795RCSA+T supports VCC from 2.72V to 5.5V per Absolute Maximum Ratings, so it can interface with 5V systems-but only as a supervisory element for downstream 3.0V/3.3V logic. Its reset threshold (2.55V–2.70V) is fixed for 3.0V rails; using it to monitor a 5V supply would cause premature reset. For 5V supervision, a different device (e.g., MAX690 family) is required. MAX795RCSA+T's PFI input, however, can monitor 5V auxiliary rails independently via external resistor divider.