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LM385M-NOPB

LM385M/NOPB Shunt Voltage Reference, Adjustable ±2%, 8-SOIC

MPNLM385M/NOPB
Active

Texas Instruments LM385M/NOPB, adjustable shunt voltage reference, ±2% tolerance, 1.24V to 5.3V output, 55 µA min cathode current, 20 mA output, 50 µVrms noise, 150ppm/°C drift, 8-SOIC, 0°C to 70°C.

$1.0500Ref. price · indicative, final on quote
Texas Instruments LM385M/NOPB datasheet (PDF)
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Jul 2026

Specifications

LM385M/NOPB specifications
ParameterValue
Output typeAdjustable
MountingSurface Mount
Reference typeShunt
Voltage - output5.3 V
Voltage - output (Min (Fixed))1.24V
Output current20 mA
Current - cathode55 µA
Operating temperature0°C~70°C(TA)
PackageTube
Tolerance±2%
Case8-SOIC (0.154\", 3.90mm Width)
Noise - 10Hz to 10kHz50µVrms
Temperature coefficient150ppm/°C

Product details

Shunt reference basics for the BOM

It operates like a low-power Zener, regulating the voltage across its terminals by shunting current through an external series resistor.

Setting the bias current matters

As a shunt reference, the LM385M/NOPB requires a minimum cathode current of 55 µA to maintain regulation. The external series resistor must be sized to deliver this current plus the load current at the minimum supply voltage. Maximum output current is 20 mA. For noise-sensitive circuits like ADC references, this should be factored into the signal chain budget.

Frequently asked questions

What is the minimum cathode current for LM385M/NOPB?

The minimum cathode current required for regulation is 55 µA. The external series resistor must be selected to ensure this current flows under all load conditions.

Can LM385M/NOPB replace TL431?

Both are shunt references, but the TL431 typically has a 2.5 V reference and higher output current. The LM385M/NOPB has a 1.24 V minimum output and 20 mA maximum output. Pinout and resistor divider values differ, so a direct replacement is not guaranteed without circuit modification.