Hitting speeds 100 times faster than conventional devices, the third-generation Q845 ET single-chip envelope tracker from Quantace Inc. enables power-amplifier efficiency to reach theoretical limits and boost peak transmit power. Thanks to qBoost technology, it exhibits a response time equal to a 400-MHz switcher. The Q845 employs MIPI Alliance ET control and envelope interfaces, enabling seamless deployment in 4G/LTE baseband and transceiver chipsets. It also uses a combination of switching and linear supplies to deliver a controlled voltage to the amp. Evaluation kits are available now with sampling in the first quarter of 2012.