1 Introduction

Optical modules are normally supplied from 3.3 V. However, the voltage deviation of initial power supply could be quite high, up to +/-10%. Additional details can be found in Buck-Boost Converters Solving Power Challenges in Optical Modules. Figure 1-1 shows the block diagram of optical module. The trans-impedance amplifier (TIA) on the receive side requires much higher voltage accuracy to guarantee its functionality and performance. To achieve this, a voltage stabilizer after initial 3.3 V power supply is necessary.

Figure 1-1 Block Diagram of Optical Module

Considering that optical modules are hot-plugged and small-sized, voltage stabilizer in optical module has several requirements:

1. A load capacity
2. Smaller than 2mm×2mm size
3. 90% efficiency. at least
4. Maximum 10mV output voltage ripple