Analog Devices Inc./Maxim Integrated DS1836AS-10+T&R

Overview

DS1836AS-10+T&R from Maxim Integrated is a 5V microprocessor supervisory circuit with power-switching, non-maskable interrupt (NMI), and precision reset generation. It monitors VCC for out-of-tolerance conditions, asserts RST for 350ms after recovery, switches VOUT between VCC and VBAT at 4.25V–4.50V (trip) / 3.90V–4.00V (return), and triggers NMI when IN falls below 1.15V–1.35V - used in PIC-based embedded systems requiring dual-supply failover and early power-fail warning.

For engineers reviewing the DS1836AS-10+T&R datasheet, DS1836AS-10+T&R pinout, DS1836AS-10+T&R application, or DS1836AS-10+T&R equivalent, key selection criteria include VCC reset threshold tolerance (±0.125V), guaranteed 350ms reset pulse width, push-pull RST output capable of valid logic down to 0V supply, NMI trip accuracy (±0.1V), and SO-8 package compatibility with industrial temperature range (-40°C to +85°C).

Technical Context

The DS1836AS-10+T&R implements a dual-threshold comparator architecture for VCC monitoring: one path controls RST assertion/deassertion with hysteresis (VCCRTP − VCCFTP ≈ 0.1V), another governs power switching between VCC and VBAT. Its internal bandgap reference enables stable 1.25V sense point for the IN pin, supporting user-defined voltage dividers for early power-loss detection upstream of main regulation.

It integrates three independent functional blocks: (1) a precision reset generator with fixed 350ms timeout, (2) an analog power switch with automatic switchover and hold-off logic, and (3) an open-drain NMI comparator with high-impedance input and external pull-up requirement - all operating from a single 1.2V–5.5V supply range without external components beyond R1/R2 for IN scaling.

Key Specifications

Pinout & Package

DS1836AS-10+T&R is supplied in an 8-pin SOIC (150-mil width) surface-mount package, RoHS-compliant and tape-and-reel packaged per +T&R suffix.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX691ACPE+ and TPS3823-50DBVR, the DS1836AS-10+T&R uniquely combines 5V reset supervision, dual-supply power switching, and NMI generation in a single SO-8 package - delivering system-level power resilience not achievable with either alternative alone.

Availability

DS1836AS-10+T&R is available at Aetrix Electronics and suitable for industrial PLC I/O modules, PIC-based data loggers, medical point-of-care devices, and smart energy meters requiring stable component supply and long-term lifecycle support.

Supply support for DS1836AS-10+T&R 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, communications, and computing applications.

The DS1836 family was designed specifically for microprocessor-based systems needing coordinated power monitoring, battery switchover, and early-failure warning - targeting PIC, 8051, and other legacy embedded controllers in harsh environments.

FAQ

What is the exact VCC reset threshold range for DS1836AS-10+T&R?

The DS1836AS-10+T&R has a specified VCC reset threshold range of 4.25V (minimum) to 4.50V (maximum) at 25°C, with guaranteed operation across -40°C to +85°C. This corresponds to the "-10" variant designation in the DS1836 family, optimized for 5V systems with tighter tolerance than the "-05" version. The DS1836AS-10+T&R uses this threshold to assert RST during brownout and maintain it for ≥350ms after VCC recovery.

Does DS1836AS-10+T&R support true 0V operation of the RST output?

Yes, the DS1836AS-10+T&R features a push-pull RST output that remains valid (driving low or high) even when VCC drops to 0V, provided VBAT is present. This is achieved through internal charge-pump-assisted output stage design, enabling safe microcontroller shutdown sequencing. Unlike open-drain alternatives, no external pull-up is required for RST, though a 100kΩ pull-down may be added to ensure defined state during total power loss.

How does the NMI function work in DS1836AS-10+T&R?

The NMI output of DS1836AS-10+T&R is an open-drain signal triggered when the voltage at the IN pin falls below 1.25V ±0.1V. This high-impedance input accepts user-defined voltage dividers to monitor upstream supplies (e.g., raw DC input), providing early warning ~10–100ms before RST assertion. A 10kΩ external pull-up resistor is required on NMI, and the DS1836AS-10+T&R guarantees ≤1μs propagation delay from IN trip to NMI activation.

Can DS1836AS-10+T&R operate from a 3.3V supply?

No, DS1836AS-10+T&R is a 5V-specific variant: its VCC reset threshold (4.25–4.50V) and power-switch thresholds (3.80–4.00V) are designed exclusively for nominal 5V systems. For 3.3V operation, Maxim specifies DS1836CS-10+T&R (with 2.80–2.97V reset threshold) or DS1836CS-20+T&R (2.67–2.80V). Using DS1836AS-10+T&R on 3.3V will prevent proper reset assertion and disable power switching functionality.

What package type and compliance status does DS1836AS-10+T&R have?

DS1836AS-10+T&R is supplied in an 8-pin SOIC (150-mil width) package with lead (Pb)-free, RoHS-compliant finish. The "+T&R" suffix confirms tape-and-reel packaging per EIA-481 standard, suitable for automated SMT assembly. Pin pitch is 1.27mm, body width is 3.9mm, and maximum height is 1.75mm - compatible with standard SO-8 footprints and reflow profiles per JEDEC J-STD-020.