SKY74068-21数据手册Skyworks中文资料规格书

描述 Description

The SKY74068-21 transmitter is a highly integrated device fordual-band Code Division Multiple Access (CDMA) femtocells. TheSKY74068-21 supports femtocells in the cellular CDMA andPersonal Communications System (PCS) modes.

The device requires a minimum number of external componentsto complete a CDMA radio subsystem. Included on-chip are thebaseband filter, direct upconversion In-Phase and Quadrature (I/Q)mixers, variable gain power amplifier (PA) drivers, a fullyintegrated Voltage Controlled Oscillator (VCO) with Local Oscillator(LO) generation blocks, and a dual-mode fractional-N/integer-NPhase Locked Loop (PLL).

External components needed for operation include bias resistors,bypass capacitors, and passives to comprise the PLL loop filter.

The signal enters the chip as an analog baseband I/Q signal. It isfiltered by the baseband filter and upconverted to the desired RFtransmit frequency. The signal is amplified by one of twoupconverters, depending on whether the chip is operating incellular or PCS mode. The resulting signal is fed through theappropriate PA driver stage to provide variable output power andto drive the external PA. The signal is then filtered by an externalSurface Acoustic Wave (SAW) filter and sent to the PA to obtainthe final rated power.

特性 Features

• Low power consumption in all operating modes
• Direct upconversion architecture
• Device controlled using a three-wire read/write serial bus interface with independent supply voltage
• Baseband RC filter to reject receive band noise
• Fully integrated VCO with auto-tuning
• Dual-mode fractional-N/integer-N PLL
• Variable gain PA drivers
• Differential cellular driver output matched to 200 
• Single-ended PCS driver output matched to 50 
• Transmit power control with >75 dB dynamic range
• Low current consumption at low transmit power minimizes current consumption and noise
• Hardware TX_ENABLE for gated mode operation
• RFLGA™ (32-pin, 5 x 5 x 1 mm) package with downset paddle (MSL3, 260 °C per JEDEC J-STD-020)

应用 Application

• Small Cells