Adafruit Precision LM4040 Voltage Reference Breakout - 2.048V and 4.096V
Breakout board with two shunt-type LM4040 voltage references: 2.048 V (suited to 3.3 V systems) and 4.096 V (suited to 5 V systems), each 0.1% accuracy with 750 Ω bias resistors. Use for calibrating ADCs, multimeters, or microcontroller analog inputs.
Pinout
- VIN1
Input supply for the LM4040 voltage-reference breakout. Adafruit says to power the board with about 5V-12V, or 3V when only the 2.048V reference is needed; the official Eagle schematic connects JP1 pin 1 to the VIN net.
Type · PowerVoltage · about 5V-12V input; 3V supports only the 2.048V reference, per Adafruit product page - GND2
Ground reference. The official Eagle schematic connects JP1 pin 2 to the GND net.
Type · GroundVoltage · 0V reference - 2.048V3
Precision 2.048V reference output for measurement/reference use, not a regulator output for powering loads. The official Eagle schematic connects JP1 pin 3 to the 2.048V net.
Type · UnknownVoltage · 2.048V reference output, 0.1% accuracy per Adafruit product page - 4.096V4
Precision 4.096V reference output for measurement/reference use, not a regulator output for powering loads. The official Eagle schematic connects JP1 pin 4 to the 4.096V net.
Type · UnknownVoltage · 4.096V reference output, 0.1% accuracy per Adafruit product page
| Pin | Position | Type | Function | Voltage |
|---|---|---|---|---|
| VIN | 1 | Power | Input supply for the LM4040 voltage-reference breakout. Adafruit says to power the board with about 5V-12V, or 3V when only the 2.048V reference is needed; the official Eagle schematic connects JP1 pin 1 to the VIN net. | about 5V-12V input; 3V supports only the 2.048V reference, per Adafruit product page |
| GND | 2 | Ground | Ground reference. The official Eagle schematic connects JP1 pin 2 to the GND net. | 0V reference |
| 2.048V | 3 | Unknown | Precision 2.048V reference output for measurement/reference use, not a regulator output for powering loads. The official Eagle schematic connects JP1 pin 3 to the 2.048V net. | 2.048V reference output, 0.1% accuracy per Adafruit product page |
| 4.096V | 4 | Unknown | Precision 4.096V reference output for measurement/reference use, not a regulator output for powering loads. The official Eagle schematic connects JP1 pin 4 to the 4.096V net. | 4.096V reference output, 0.1% accuracy per Adafruit product page |
Pin details
4 connections- VIN1
Input supply for the LM4040 voltage-reference breakout. Adafruit says to power the board with about 5V-12V, or 3V when only the 2.048V reference is needed; the official Eagle schematic connects JP1 pin 1 to the VIN net.
PowerVoltage · about 5V-12V input; 3V supports only the 2.048V reference, per Adafruit product page - GND2
Ground reference. The official Eagle schematic connects JP1 pin 2 to the GND net.
GroundVoltage · 0V reference - 2.048V3
Precision 2.048V reference output for measurement/reference use, not a regulator output for powering loads. The official Eagle schematic connects JP1 pin 3 to the 2.048V net.
UnknownVoltage · 2.048V reference output, 0.1% accuracy per Adafruit product page - 4.096V4
Precision 4.096V reference output for measurement/reference use, not a regulator output for powering loads. The official Eagle schematic connects JP1 pin 4 to the 4.096V net.
UnknownVoltage · 4.096V reference output, 0.1% accuracy per Adafruit product page
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