Test an AMS1117 3.3V linear regulator
The LD1117 is a low drop fixed and adjustable voltage regulator, available from a number of manufacturers including UTC and ST.
The component I have (obtained from a seller on aliexpress) is marked: AMS1117-3.3 H1518 in a SOT-223 package.
As given in the datasheet:
- dropout voltage (Vin - Vout): 1.1V typical, 1.3V max
- Vin max: 15V
- current limit: 1.1A typical, 1.5A max
- pin out (from left front): ground, Vout, Vin
Circuit recommendations:
- 22µF tantalum output capacitor
Some DMM measurements, with a 10kΩ output load:
| Vin | Iin | Vout | Iout | Pin:Pout |
|---|---|---|---|---|
| 5.09V | 2.68mA | 3.29V | 333µA | 13.64mW : 1.1mW |
The inefficiency of a linear regulator is clear to see - we're dissipating 12.74mW in the 1117, far more power than is actually delivered to the load. But they're convenient!
NB: these diagrams use the custom AMS1117 module fritzing part
