Please note: this product is being discontinued and is not recommended for new designs.
The Q845 ultra-fast power supply is designed for envelope tracking (ET) for 3G/4G/LTE RF PAs. It also supports average power tracking (APT).
Using patented qBoostTM technology, the Q845 simultaneously combines the high efficiency of a switching power supply with the responsiveness and low noise of a linear power supply. An innovative combining network optimizes the blend of these supply technologies and also enables the Q845 to dynamically boost its output voltage above its input voltage to track modulation peaks.
With this approach, the Q845 provides an efficient PA supply voltage with a slew rate up to 100V/s, continuously adjusting the PA supply voltage to precisely track the modulation envelope, thus maximizing PA efficiency and peak power. This performance is achieved while still meeting ACLR, EVM, and Receive Band noise specifications. Where APT is adequate in the mid-power range of the PA, the Q845 seamlessly transitions between ET and APT as needed. Figure 1 shows a functional block diagram.
| Skyworks Solutions, Inc. | |
|---|---|
| Product Category | IC Voltage Regulators |
| Product Number | Q845 |
| Product Name | Ultra-Fast Boosting Power Supply for 3G/4G/LTE PA Envelope Tracking |
| Package Type | Other; WLCSP, 24-pin |