LM4040 Datasheet PDF – Shunt Voltage Reference

Part Number : LM4040

Function : Precision Micropower Shunt Voltage Reference

Package : SOT-23, SC-70, TO-92

Manufacturers : Texas Instruments, Microchip Semiconductor, National Semiconductor


LM4040 Shunt Voltage Reference

Description :

The LM4040 series of shunt voltage references are versatile, easy-to-use references that cater to a vast array of applications.
The 2-pin fixed-output device requires no external capacitors for operation and is stable with all capacitive loads. Additionally, the reference offers low dynamic impedance, low noise, and low temperature coefficient to ensure a stable output voltage over a wide range of operating currents and temperatures.

The LM4040 uses fuse and Zener-zap reverse breakdown voltage trim during wafer sort to offer four output voltage tolerances, ranging from 0.1% (max) for the A grade to 1% (max) for the D grade. Thus, a great deal of flexibility is offered to designers in choosing the best cost-to-performance ratio for their applications.

Packaged in space-saving SC-70 and SOT-23-3 packages and requiring a minimum current of 45 μA (typ), the LM4040 also is ideal for portable applications. The LM4040xI is characterized for operation over an ambient temperature range of –40°C to 85°C. The LM4040xQ is characterized for operation over an ambient temperature range of –40°C to 125°C.


1. Small SOT-23 Package
2. No Output Capacitor Required
3. Tolerates Capacitive Loads
4. Fixed Reverse-Breakdown Voltages of 1.225V, 2.500V, 4.096V, and 5.000V
5. Adjustable Reverse-Breakdown Version

Pinouts :
LM4040 datasheet


1. Data-Acquisition Systems
2. Power Supplies and Power-Supply
3. Instrumentation and Test Equipmen
4. Process Controls
5. Precision Audio
6. Automotive Electronics
7. Energy Management
8. Battery-Powered Equipment


Official Homepage : http://www.ti.com/product/LM4040

LM4040 Datasheet PDF Download

LM4040 pdf

Other data sheets within the file : LM4040A10IDBZR, LM4040A10IDBZRG4, LM4040A10IDBZT, LM4040A10IDBZTG4

TL431 Datasheet – Shunt Regulator Diode – Motorola

Part Number : TL431

Function : Programmable Precision References

Package : TO 92, DIP 8 Pin, DIP 8 Pin Type

Manufactures : Motorola

Images and Pinouts :
TL431 Datasheet

Description :

The TL431, A, B integrated circuits are three–terminal programmable shunt regulator diodes. These monolithic IC voltage references operate as a low temperature coefficient zener which is programmable from V refto 36 V with two external resistors. These devices exhibit a wide operating current range of 1.0 mA to 100 mA with a typical dynamic impedance of 0.22 Ω. The characteristics of these references make them excellent replacements for zener diodes in many applications such as digital voltmeters, power supplies, and op amp circuitry. The 2.5 V reference makes it convenient to obtain a stable reference from 5.0 V logic supplies, and since the TL431, A, B operates as a shunt regulator, it can be used as either a positive or negative voltage reference.


1.  Programmable Output Voltage to 36 V
2. Voltage Reference Tolerance: ±0.4%, Typ @ 25°C (TL431B)
3. Low Dynamic Output Impedance, 0.22 ΩTypical
4. Sink Current Capability of 1.0 mA to 100 mA
5. Equivalent Full–Range Temperature Coefficient of 50 ppm/°C Typical
6. Temperature Compensated for Operation over Full Rated Operating Temperature Range
7. Low Output Noise Voltage

Block Diagram

TL431 Diagram

TL431 Datasheet