Driver circuit for a camera voice coil motor

摘要

A driver circuit for a camera voice coil motor (VCM) is described. A first power switch selectively conducts current from a VCM node to a power supply node, and a second power switch selectively conducts current from the VCM node to a power return node. A pulse width modulation circuit controls the first and second power switches. In another embodiment, a switch mode current control circuit sources VCM current alternately from the power supply node and the power n node, into the VCM node. Other embodiments are also described and claimed.

主权项

1. A camera module comprising:
a camera lens; a voice coil motor, VCM, coupled to move the camera lens and having first and second terminals, the second terminal coupled to a power return node without any intervening active devices; and a driver circuit having a switch mode current control circuit to source VCM coil current into the first terminal of the VCM alternately from a power supply node and the power return node.