# REF19x Series: Precision Micropower Voltage References

## Features

* **Initial Accuracy:** ±2 mV maximum
* **Temperature Coefficient:** 5 ppm/°C maximum
* **Low Supply Current:** 45 μA maximum (Sleep mode: 15 μA)
* **Low Dropout Voltage:** Supplies as low as 100 mV above the output voltage
* **Load Regulation:** 4 ppm/mA
* **Line Regulation:** 4 ppm/V
* **High Output Current:** 30 mA
* **Short-circuit Protection**
* **Extended Industrial Temperature Range:** -40°C to +85°C (typical performance to +125°C)

## General Description

* Uses patented temperature drift curvature correction and laser trimming for accuracy.
* Micropower, low dropout voltage devices.
* Sleep mode reduces supply current when enabled.
* Available in 8-lead SOIC_N, PDIP, and TSSOP packages (electrical grade limitations for PDIP & TSSOP).
* Also available in die form.

## Pin Configuration

* **Test Pins (TP1 & TP5):** Reserved for in-package Zener zap; leave unconnected.
Resistance varies widely.
* **NC:** No Connect
* **OUTPUT:** Output Voltage pin
* **SLEEP:** Enables low-power sleep mode (TTL/CMOS level)
* **GND:** Ground

## Part Numbers & Nominal Output Voltage

* REF191: 2.048 V
* REF192: 2.50 V
* REF193: 3.0 V (not explicitly listed but implied as standard)
* REF194: 3.3 V (not explicitly listed but implied as standard)
* REF195: 5.0 V (not explicitly listed but implied as standard)

## Electrical Characteristics (REF191 Example)

* **Initial Accuracy:** 2.046-2.050 V (E Grade), varying slightly for other grades.
* **Line Regulation:** 2-4 ppm/V (E Grade), higher for other grades
* **Load Regulation:** 4-10 ppm/mA (E Grade), higher for other grades
* **Dropout Voltage:** Varies based on VS and ILOAD (example: 0.95V at VS=3.15V, ILOAD=2mA)
* **Sleep Pin Logic:** Specific input voltage and current levels defined for enabling sleep mode.
* **Supply Current:** 45 μA (no load), 15 μA (sleep mode)

## Applications

* Voltage Reference Connections
* Current-Boosted References
* Negative Precision Reference
* Stacking Reference ICs
* Precision Current Source
* Membrane Switch-Controlled Power Supply
* Low Power Strain Gauge Circuit