Analog Devices Inc./Maxim Integrated DS1815-5+

Overview

DS1815-5+ from Maxim Integrated (now Analog Devices) is a precision 5% tolerance voltage supervisor IC that monitors VCC and asserts an active-low reset signal during power failure or brownout. It delivers 150ms reset pulse width, push-pull output, and operates from 0V to 5.5V supply across –40°C to +85°C - used in microprocessor reset management for embedded controllers and industrial PLCs.

For engineers reviewing the DS1815-5+ datasheet, DS1815-5+ pinout, DS1815-5+ application, or DS1815-5+ equivalent, key selection factors include its guaranteed 2.98V–3.15V trip threshold, 150ms minimum reset timeout, push-pull drive capability up to 10mA sink, ultra-low 28µA typical operating current, and TO-92/SOT-23 package compatibility.

Technical Context

The DS1815-5+ integrates a temperature-compensated bandgap reference and comparator to detect VCC deviations beyond ±5% of nominal 3.3V. Its internal timing circuit ensures RST remains asserted for ≥100ms and ≤250ms after VCC returns to tolerance, with typical 150ms duration.

It features a CMOS push-pull output stage capable of sourcing 350µA at 2.4V and sinking 10mA at 0.4V, eliminating external pull-up resistors. The device asserts reset down to 0V VCC, enabling valid reset signaling even during full power collapse.

Key Specifications

Pinout & Package

DS1815-5+ is available in both TO-92 and SOT-23 packages. Both variants share identical 3-pin configuration and functional pin mapping.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage supervisor applications.

Compared with TPS3808G50DBVR and MAX6326UT46D3+, the DS1815-5+ uniquely supports 3.3V rail supervision with 5% accuracy, 0V-valid reset signaling, and ultra-low 28µA quiescent current - making it optimal for low-power 3.3V embedded systems where brownout margin and energy efficiency are critical.

Availability

DS1815-5+ is available at Aetrix Electronics and suitable for industrial PLCs, embedded microcontroller reset circuits, point-of-sale terminals, and smart meter power-fail detection requiring stable component supply and long-term lifecycle support.

Supply support for DS1815-5+ 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 (via acquisition of Maxim Integrated) designs high-performance analog, mixed-signal, and power management ICs for precision sensing, power integrity, and system reliability.

The DS1815-5+ belongs to Maxim's EconoReset™ family of voltage supervisors, engineered specifically for cost-sensitive, space-constrained embedded systems requiring accurate, low-power, and fail-safe power monitoring.

FAQ

What is the exact VCC trip voltage range for DS1815-5+?

The DS1815-5+ has a guaranteed VCC trip point of 2.98V to 3.15V at +25°C, corresponding to ±5% tolerance around a nominal 3.3V supply. This range is temperature-compensated and specified over the full –40°C to +85°C operating range per the datasheet's DC electrical characteristics table. The DS1815-5+ uses an internal precision bandgap reference to maintain this accuracy without external calibration.

Does DS1815-5+ require an external pull-up resistor on the RST pin?

No, DS1815-5+ does not require an external pull-up resistor because it features a push-pull output stage. The RST pin actively drives high or low depending on VCC status, eliminating reliance on passive components. This simplifies design, reduces BOM count, and improves noise immunity compared to open-drain supervisors - a key advantage confirmed in the DS1815-5+ block diagram and pin description.

How long is the reset pulse asserted after VCC returns to tolerance?

The DS1815-5+ holds the RST pin active low for a minimum of 100ms and a maximum of 250ms after VCC rises above the trip threshold, with a typical duration of 150ms. This timing is internally generated and independent of external components, ensuring consistent processor stabilization across temperature and supply variations - as verified in the AC Electrical Characteristics table under "RESET Active Time (tRST)".

Can DS1815-5+ operate when VCC drops below 1V?

Yes, DS1815-5+ asserts a valid active-low reset signal even as VCC collapses to 0V. Its output stage remains functional down to 0V VCC, enabling fail-safe signaling during complete power loss. This behavior is explicitly documented in the "RST VALID TO 0 VOLTS VCC" application diagram and confirmed in the Absolute Maximum Ratings section, distinguishing DS1815-5+ from many competitors with higher minimum operating voltage requirements.

What packages are available for DS1815-5+?

DS1815-5+ is offered in both TO-92 through-hole and SOT-23 surface-mount packages. Both variants share identical pinout (RST-VCC-GND), electrical specifications, and thermal performance. The SOT-23 version supports automated assembly and space-constrained layouts, while the TO-92 variant facilitates prototyping and manual repair - as detailed in the Pin Assignment section and mechanical drawings referenced in the datasheet.