Analog Devices ADP1109AAR-3.3, Step-Up DC-DC Converter, Fixed 3.3V Output, 1.2A Switch, 120kHz, 8-SOIC, Surface Mount, 0°C to 70°C.
| Parameter | Value |
|---|---|
| Output type | Fixed |
| Mounting type | Surface Mount |
| Voltage - input | 9V |
| Voltage - output (Min (Fixed)) | 3.3V |
| Current - output | 1.2A (Switch) |
| Frequency | 120kHz |
| Number of outputs | 1 |
| Operating temperature | 0°C ~ 70°C |
| Package | Bulk |
| Function | Step-Up |
| Topology | Boost |
| Case | 8-SOIC (0.154\", 3.90mm Width) |
| Output configuration | Positive |
| Synchronous rectifier | No |
The ADP1109AAR-3.3 is a fixed 3.3 V output step-up (boost) switching regulator from Analog Devices, built around a 1.2 A internal switch. It takes an input from 2 V up to 9 V.
The 1.2 A switch current is the hard ceiling. The 2 V minimum input means it can run from two alkaline cells in series. The 9 V input maximum keeps it off higher-voltage rails.
The LT1305CS8#PBF is a close functional peer — also a boost converter in an SOIC-8, with a 1.8 V minimum input and a 2.5 A switch, but at a 155 kHz switching frequency. The ADP1111 series (ADP1111ANZ-5, ADP1111ARZ) can step up or step down, but the switch current is only 0.4 A, so it won't match the 1.2 A rating of this part.
No — this is a fixed 3.3 V output version. The feedback network is internal and not adjustable. To get a 5 V output you would need the adjustable version of the ADP1109 or a different part.