Analog Devices Inc./Maxim Integrated DS1233-5+

Overview

DS1233-5+ from Analog Devices is a 5V microprocessor supervisory circuit in TO-92 package that monitors V_CC for out-of-tolerance conditions (4.50–4.75 V trip point), asserts reset for 350 ms after power recovery or pushbutton release, and integrates internal 5 kΩ pull-up and precision temperature-compensated voltage reference. It serves as a system-level power-fail detector and manual reset controller in embedded microcontroller applications.

For engineers reviewing the DS1233-5+ datasheet, DS1233-5+ pinout, DS1233-5+ application, or DS1233-5+ equivalent, key selection criteria include V_CC trip accuracy (±5%), guaranteed 350 ms reset pulse width, pushbutton debounce capability, operating temperature range (–40°C to +85°C), and TO-92 package compatibility with legacy through-hole designs.

Technical Context

The DS1233-5+ implements dual-function supervision: first, a comparator-based 5V power monitor using a temperature-compensated reference to detect V_CC falling below 4.50 V (min) or rising above 4.75 V (max); second, an edge-triggered pushbutton interface that debounces switch closure and generates a precisely timed 350 ms active-low reset pulse upon release.

Its internal architecture includes a 350 ms delay timer, open-drain RST output with integrated 5 kΩ pull-up, and voltage-sensing circuitry tolerant to V_CC slew rates as slow as 300 μs across the 4.00–4.75 V window. No external RC timing components are required.

Key Specifications

Pinout & Package

DS1233-5+ is supplied in a 3-pin TO-92 package (lead-free, RoHS-compliant). Pin 1 is Ground, Pin 2 is open-drain RESET output, and Pin 3 is V_CC input. The device has no fourth pin - SOT-223 variants (e.g., DS1233Z-5+) include an additional ground pin, but DS1233-5+ uses only three terminals.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX809S+T and TPS3808G01DBVR, the DS1233-5+ uniquely combines fixed ±5% 5V supervision, guaranteed 350 ms reset hold, and hardware pushbutton debounce in a 3-pin TO-92 package - eliminating both external timing components and firmware-level switch handling.

Availability

DS1233-5+ is available at Aetrix Electronics and suitable for industrial control systems, legacy instrumentation, point-of-sale terminals, and energy metering applications requiring stable component supply and long-term manufacturability.

Supply support for DS1233-5+ 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

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.

The DS1233-5+ belongs to the EconoReset family of supervisory circuits designed specifically for cost-sensitive, space-constrained microcontroller systems needing reliable power-on and manual reset functionality without external components.

FAQ

What is the exact V_CC trip point range for DS1233-5+?

The DS1233-5+ has a guaranteed V_CC trip point range of 4.50 V to 4.75 V, corresponding to ±5% tolerance around the nominal 4.625 V threshold. This specification is tested and ensured across the full –40°C to +85°C operating temperature range and is derived from the device's internal temperature-compensated voltage reference. The DS1233-5+ does not support adjustable thresholds - this fixed range is intrinsic to the part number.

Does DS1233-5+ require an external capacitor for pushbutton operation?

Yes, DS1233-5+ requires a capacitor between 100 pF and 0.01 μF connected from the RST pin to ground for proper pushbutton debounce operation. This capacitor works with the device's internal timing circuit to filter switch bounce. For applications demanding higher reset current drive, a minimum 500 pF capacitor plus an external 1 kΩ pull-up resistor is recommended. The DS1233-5+ will not generate a valid reset pulse without this capacitor.

Can DS1233-5+ be used with 3.3V microcontrollers?

No, DS1233-5+ is specified exclusively for 5V systems: its V_CC trip point is fixed at 4.50–4.75 V, and its absolute maximum V_CC rating is 5.5 V. It is not compatible with 3.3V supply rails. For 3.3V supervision, Analog Devices offers the DS1233A-5+ variant, which has a 2.80–2.97 V trip range. Using DS1233-5+ on a 3.3V rail would result in continuous reset assertion.

What is the function of Pin 2 on DS1233-5+?

Pin 2 of DS1233-5+ is the open-drain RESET output. It actively pulls low during reset conditions - including power-up, power-down, and pushbutton release - and floats high otherwise. Because it is open-drain, DS1233-5+ relies on either its internal 5 kΩ pull-up resistor or an external pull-up to establish a defined high state. This pin connects directly to the reset input of the target microcontroller or digital logic.

Is DS1233-5+ RoHS-compliant and lead-free?

Yes, DS1233-5+ is RoHS-compliant and lead-free, as indicated by the "+" suffix in the part number per Analog Devices' packaging nomenclature. The TO-92 package meets JEDEC standards for lead-free soldering (260°C for 10 seconds), and the device is rated for storage temperatures from –55°C to +125°C. Full compliance documentation, including material declarations, is available from Analog Devices' official product page for DS1233-5+.