Patent ID: 8493145

Claim:
An apparatus, comprising: a quantizer adapted to quantize a signal into one of first, second and third levels in a non-uniform manner, wherein the signal is quantized into the first level in response to a value of the signal being in a first range, wherein the signal is quantized into the second level in response the value of the signal being in a second range, wherein the signal is quantized into the third level in response the value of the signal being in a third range, and wherein the size of the third range is different than at least one of the sizes of the first and second ranges; and a switching power amplifier, comprising: a switching network; and a controller adapted to: set the switching network in a first configuration to produce a forward current through a load in response to the quantized signal being in the first level; set the switching network in a second configuration to produce a reverse current through the load in response to the quantized signal being in the second level; and alternately set the switching network between third and fourth configurations, both of which produce no current through the load in response to the quantized signal being in the third level.