The document introduces the characteristics of the LT3905, including its working principle, application scenarios, advantages and disadvantages.
The LT3905 is a boost DC/DC converter featuring high-side APD current monitoring over five decades of dynamic range with better than 2% relative accuracy. It includes an integrated Schottky diode and a fast APD current limiter with an indicator to protect the device during overload conditions.
Key features include programmable loss-of-signal indicators, adjustable output voltage for dynamic bias control, and internal compensation coupled with soft-start. The device operates from a 2.7V to 12V input range and is available in a compact 8mm x 3mm 16-lead QFN package.
| Operating Voltage Range | 2.7V to 12V |
|---|---|
| Supply Current (Shutdown) | <1pA |
| Switching Frequency Range | 0.9 MHz to 2.2 MHz |
| Maximum Duty Cycle (fsw=0V) | 95% |
It is designed to bias avalanche photodiodes (APD) in optical receivers.
It offers better than 2% relative accuracy over the 3A to 3mA range.