Analog Devices Inc./Maxim Integrated DS1233AZ-15/T&R

Overview

DS1233AZ-15/T&R from Maxim Integrated is a 3.3V microprocessor supervisory circuit with 15% VCC trip point (2.64–2.80V), pushbutton reset debouncing, and guaranteed 350ms reset pulse width. It provides power-on reset, power-fail detection, and external manual reset control in SOT-223 package. Used in embedded controllers requiring reliable power sequencing and brownout protection.

For engineers reviewing the DS1233AZ-15/T&R datasheet, DS1233AZ-15/T&R pinout, DS1233AZ-15/T&R application, or DS1233AZ-15/T&R equivalent, key selection criteria include VCC trip accuracy (±8% over temp), internal 5kΩ pull-up, pushbutton debounce timing (250–450ms), and guaranteed 350ms reset hold time after power recovery or button release.

Technical Context

The DS1233AZ-15/T&R implements dual-function supervision: precision voltage monitoring via temperature-compensated bandgap reference and comparator, plus edge-triggered pushbutton reset with hardware debounce. Its reset output is actively driven low during fault conditions and remains asserted for ≥250ms after VCC returns to tolerance.

It operates across -40°C to +85°C with supply voltage range 1.2V to 5.5V, draws only 50μA typical quiescent current, and features internal 5kΩ pull-up on RST-enabling direct connection to microcontroller reset inputs without external components.

Key Specifications

Pinout & Package

SOT-223 package with 4-pin configuration: 3 active terminals (VCC, GND, RESET) plus dedicated GND pin for thermal and noise performance. Pin 4 is ground-only and must be connected to PCB ground plane.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX809SEUR+T and TPS3808G15DBVR, the DS1233AZ-15/T&R uniquely integrates pushbutton debounce and fixed 350ms reset hold in a single SOT-223 device-reducing layout area and eliminating firmware reset handling while maintaining industrial temperature operation.

Availability

DS1233AZ-15/T&R is available at Aetrix Electronics and suitable for industrial automation, medical diagnostics, smart metering, and automotive telematics requiring stable component supply and long-term lifecycle support.

Supply support for DS1233AZ-15/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) designs precision analog and mixed-signal ICs for industrial, communications, and computing applications.

The DS1233A family delivers cost-optimized microprocessor supervision with integrated voltage monitoring and pushbutton control-targeting resource-constrained embedded systems needing high reliability without software overhead.

FAQ

What is the exact VCC trip voltage range for DS1233AZ-15/T&R?

The DS1233AZ-15/T&R has a guaranteed VCC trip point range of 2.64V to 2.80V at 25°C, corresponding to 15% undervoltage tolerance relative to a nominal 3.3V supply. This specification holds across the full operating temperature range (-40°C to +85°C), with typical value 2.72V. The DS1233AZ-15/T&R uses a precision temperature-compensated voltage reference to maintain this accuracy without external calibration.

Does DS1233AZ-15/T&R require an external capacitor for pushbutton operation?

Yes, DS1233AZ-15/T&R requires a capacitor between 100pF and 0.01μF connected from the RESET pin to ground for proper pushbutton debounce operation. This capacitor stabilizes the RST line during switch transitions and enables the internal timer to detect valid release events. For applications needing higher reset current drive, a minimum 500pF capacitor with a parallel 1kΩ external pull-up resistor is recommended. The DS1233AZ-15/T&R does not function correctly with pushbuttons without this capacitor.

What is the reset pulse width behavior of DS1233AZ-15/T&R during power recovery?

Upon VCC returning to within tolerance (≥2.80V), the DS1233AZ-15/T&R holds the RESET output active low for a guaranteed minimum of 250ms, with typical duration 350ms and maximum 450ms. This timing ensures microprocessor and peripheral circuits stabilize before release. The DS1233AZ-15/T&R implements this using an internal monostable circuit independent of VCC slew rate, providing consistent reset hold time even during fast-rising supply conditions.

Can DS1233AZ-15/T&R be used with 5V microcontrollers?

No, DS1233AZ-15/T&R is specifically designed for 3.3V systems and has a VCC trip point optimized for 15% undervoltage at 3.3V (2.64–2.80V). While its absolute maximum VCC rating is 5.5V and it can tolerate 5V supply, the trip threshold remains fixed at ~2.72V-making it unsuitable for detecting 5V supply faults. For 5V applications, DS1233-15 or DS1233D-15 variants with 4.0–4.24V trip points should be selected instead of DS1233AZ-15/T&R.

What is the purpose of Pin 4 in the SOT-223 package of DS1233AZ-15/T&R?

Pin 4 in the DS1233AZ-15/T&R SOT-223 package is a dedicated ground terminal, separate from Pin 1 ground. It serves thermal and noise-performance functions: improving heat dissipation through enhanced PCB copper connection and reducing ground loop impedance for the internal voltage reference and comparator. This dual-ground design enhances measurement accuracy and stability under dynamic load conditions. Pin 4 must be connected to the system ground plane-leaving it unconnected degrades DS1233AZ-15/T&R reset threshold consistency.