REF1933AIDDCR from Texas Instruments, in a SOT-23-5. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin	Name	Type	Function
1	VBIAS	output	Bias voltage output equal to VREF/2 (1.65 V for REF1933). Used to bias bipolar signals into the midpoint of a single-supply ADC input range. Sources and sinks up to ±20 mA.
2	GND	power_in	Device ground return. All voltages are referenced to this pin.
3	EN	input	Enable input. Device is enabled when EN ≥ VIN − 0.7 V and placed in shutdown when EN ≤ 0.7 V. Shutdown current is typically 3.3 µA.
4	VIN	power_in	Input supply voltage. Recommended operating range VREF + 0.02 V to 5.5 V; absolute maximum 6 V. Dropout is 10 mV typical at IL = 0 mA.
5	VREF	output	Reference voltage output (3.3 V for REF1933). ±0.1% initial accuracy, 25 ppm/°C max temperature coefficient. Sources and sinks up to ±20 mA; stable with 0-10 µF output capacitor.

Key specifications

Parameter	Value
Manufacturer	Texas Instruments
Package	SOT-23-5
Category	PMIC
Pins	5

Ordering variants

Same part, different packaging or reel option.

REF1933AIDDCR
REF1933AIDDCT

CAD (KiCad official)

Symbol: REF1933AIDDCR
Footprint: Package_TO_SOT_SMD:SOT-23-5
3D model: SOT-23-5 (KiCad packages3D, STEP)

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

Datasheet: Texas Instruments datasheet (32 pp, sha256 193572512ed1817b, retrieved 2026-08-17, tier: lcsc)
Datasheet language: Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF