A wireless battery charging system includes a trickle power device (e.g., FET) that generates a trickle charging current for charging a battery and a trickle charging regulator that controls the trickle power device. A fast charging device generates a fast charging current for charging the battery, where the fast charging current is greater than the trickle charging current. A fast charging regulator controls the fast charging device. A digital control module generates a trickle charging codeword to control the trickle charging regulator and a fast charging codeword to control the fast charging regulator. Each charging regulator has a programmable current mirror that generates a mirrored current signal based on a codeword from the digital control module. The digital control module instructs the charging regulators to control the power devices to operate in a trickle charging mode, a fast charging mode, and transitions between those modes.