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.

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 · outputVoltage · 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.

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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	output	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	output	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

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