What Is the 78L05? 100mA 5V Regulator (TO-92): Pinout and Uses
October 20, 2026 4 min read
Quick answer
The 78L05 is a small linear regulator giving a fixed +5 V, 100 mA (the TO-92, low-current version of the 7805). It supplies clean 5 V to low-power sensor/logic blocks. ⚠️ Its TO-92 pinout DIFFERS from the 7805: flat face front, left to right OUTPUT / GND / INPUT.
The 78L05 is a small linear voltage regulator giving a fixed +5 V, 100 mA. It is the TO-92, low-current version of the 7805; it saves space and cost in low-power circuits. For the concept, see what is a voltage regulator.
What is the 78L05 used for?
Supplying clean 5 V to low-current (≤100 mA) sensor/logic blocks. Where the 1 A of the 7805 is not needed, its small TO-92 body is ideal.
78L05 pinout (TO-92) — DIFFERENT from the 7805!
⚠️ The TO-92 78Lxx order differs from the TO-220 78xx. Flat face front, left to right:
| Lead | Function |
|---|---|
| 1 | OUTPUT (+5 V) |
| 2 | GND |
| 3 | INPUT (Vin) |
Specifications
| Parameter | Value |
|---|---|
| Output | +5 V (fixed) |
| Current | ~100 mA |
| Input | ~7 V … 30 V |
| Body | TO-92 (also SOT-89 SMD) |
Equivalents
- 7805: the 1 A TO-220 version.
- 78L33 / 78L12: 3.3 V / 12 V in the same family.
- AMS1117: a low-dropout (LDO) alternative.
Find it in our catalog
Use the 78L05 search.
Frequently Asked Questions
What is the 78L05?+
The 78L05 is a small linear regulator giving a fixed +5 V and 100 mA. It is the TO-92, low-current version of the 7805 and is used in low-power circuits.
Is the 78L05 pinout the same as the 7805?+
No! TO-92 78L05: flat face front, left to right OUTPUT / GND / INPUT. The TO-220 7805 is INPUT/GND/OUTPUT. The order is different.
How many mA can the 78L05 drive?+
About 100 mA. For higher current use the 1 A 7805 (TO-220).
What is a 78L05 equivalent?+
The 1 A version is the 7805; in the same family the 78L33/78L12; for low dropout the AMS1117.