Analog Devices Inc./Maxim Integrated DS4303R-U+

Overview

The DS4303R-U+ from Maxim Integrated is a nonvolatile electronically programmable voltage reference IC with 5-pin SOT23 package, ±1mV adjustment resolution, 2.4V–3.6V single-supply operation, and EEPROM-persistent output voltage storage. It serves as a factory-calibratable precision reference in power-supply feedback loops, sensor biasing, and threshold-setting circuits where post-assembly trimming is required.

For engineers reviewing the DS4303R-U+ datasheet, DS4303R-U+ pinout, DS4303R-U+ application, or DS4303R-U+ equivalent, key selection criteria include its ±1mV quantization accuracy, 11–15ms/V self-adjust settling time, -40°C to +85°C operating range, 200µV_P-P (0.1Hz–10Hz) output noise, and ability to operate down to 300mV below VCC or above GND.

Technical Context

The DS4303R-U+ implements a closed-loop DAC-based self-adjust architecture: VIN is sampled, ADJ toggling initiates internal 12-bit DAC calibration until VOUT matches VIN within ±20mV tracking accuracy, then the result is stored in on-chip EEPROM. The device requires no external programming hardware-only stable VIN and a single low pulse on ADJ.

Its analog core includes a precision bandgap reference, rail-to-rail output stage capable of ±1mA drive, short-circuit protected VOUT, and integrated 95kΩ VIN pull-down and 18kΩ ADJ pull-up resistors. Temperature coefficient is specified as -31 to +6 ppm/°C at 3.0V output over +25°C to +85°C.

Key Specifications

Pinout & Package

DS4303R-U+ is housed in a lead-free 5-lead SOT23 package (3.0mm × 1.7mm × 1.3mm height), RoHS-compliant, with exposed pad not connected internally. Pin 1 is marked with a dot; top-view orientation places ADJ at pin 1, GND at pin 2, VIN at pin 3, VOUT at pin 4, and VCC at pin 5.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar electronically programmable voltage reference applications.

Compared with MAX6190AESA+ and LT6654BHS6-3.3#TRMPBF, the DS4303R-U+ uniquely integrates EEPROM storage, rail-to-rail programmability, and single-pin adjustment-enabling zero-footprint, hardware-only calibration without firmware or external DACs.

Availability

DS4303R-U+ is available at Aetrix Electronics and suitable for power-supply calibration, sensor biasing, threshold detection, and factory-trimmed instrumentation requiring stable component supply across automotive, industrial, and medical OEM programs.

Supply support for DS4303R-U+ 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, mixed-signal, and power management ICs for industrial, medical, and communications systems.

The DS4303R-U+ belongs to Maxim's programmable reference product line, engineered specifically to replace manual calibration methods with autonomous, in-circuit voltage trimming for high-mix manufacturing environments.

FAQ

What is the minimum stable voltage required on VIN to program the DS4303R-U+?

The DS4303R-U+ requires VIN to be stable within ±1mV during the entire self-adjust period. VIN must be between 0.3V and (VCC – 0.3V), with typical factory use at 1.200V ±0.001V for 1.2V output calibration. Instability exceeding ±1mV causes VOUTTA (±20mV tracking accuracy) to degrade, risking incomplete EEPROM write or inaccurate final value.

Can the DS4303R-U+ be reprogrammed after soldering onto a PCB?

Yes-the DS4303R-U+ supports full reprogramming post-assembly. Its SOT23-5 package exposes all pins, including ADJ and VIN, enabling bed-of-nails access. Reprogramming requires only stable VIN, a 100ns ADJ low pulse, and sufficient time for ∆V × tST settling (e.g., 12ms for 1V change). No reflow or disassembly is needed.

Does the DS4303R-U+ require external decoupling capacitors?

Yes-a 0.01µF ceramic capacitor must be placed between VCC and GND, mounted directly adjacent to pins 5 and 2. This is mandatory to suppress supply noise that could corrupt EEPROM writes or induce false ADJ triggering during power-up. Larger values (e.g., 0.1µF) may be added in parallel but do not replace the 0.01µF requirement.

What happens if ADJ is accidentally held low longer than tADJ during normal operation?

If ADJ is held low beyond the 100ns minimum (e.g., due to noise or layout coupling), the DS4303R-U+ will initiate a new self-adjust cycle once VIN stabilizes. This may overwrite the stored VOUT value. To prevent unintended programming, minimize ADJ trace length, avoid routing near noisy signals, and ensure no capacitance >10pF exists on the ADJ node per layout guidelines.

Is the DS4303R-U+ compatible with 1.8V logic systems?

No-the DS4303R-U+ requires VCC between 2.4V and 3.6V and has no 1.8V-compatible logic thresholds. Its ADJ input interprets logic low as <0.3×VCC (min -0.3V), so at VCC = 2.4V, VIL max is 0.72V-exceeding standard 1.8V logic low (<0.45V). Interfacing with 1.8V controllers requires level-shifting circuitry on the ADJ line.