SKY77324 Datasheet, PDF (1/24 Pages) Skyworks Solutions Inc. – iPAC PAM for Quad-Band GSM / GPRS

DATA SHEET
SKY77324: iPAC™ PAM for Quad-Band GSM / GPRS
Applications
• Quad-band cellular handsets
encompassing
- Class 4 GSM850/900
- Class 1 DCS1800 PCS1900
- Class 12 GPRS multi-slot operation
Features
• Low input power range 0 to 6 dBm
• High efficiency
- GSM850 49%
- GSM900 53%
- DCS 53%
- PCS 53%
• Internal ICC sense resistor for PAC
• Closed loop iPAC or open loop
operation with external PAC circuit
• Input/Output matching 50 Ω internal
(with DC blocking)
• 22-pin package
- Small outline 6 mm x 8 mm
- Low profile 1.2 mm maximum
• Low APC current 20 µA
• Gold plated, lead-free contacts
The SKY77324 Power Amplifier Module (PAM) is designed in a low profile (1.2 mm), compact
form factor for quad-band cellular handsets comprising GSM850/900, DCS1800, and
PCS1900 operation. The PAM also supports Class 12 General Packet Radio Service (GPRS)
multi-slot operation.
The module consists of separate GSM850/900 PA and DCS1800/PCS1900 PA blocks,
impedance-matching circuitry for 50 Ω input and output impedances, and a Power Amplifier
Control (PAC) block with an internal current-sense resistor. The custom CMOS integrated
circuit provides the internal PAC function and interface circuitry. Fabricated onto a single
Gallium Arsenide (GaAs) die, one Heterojunction Bipolar Transistor (HBT) PA block supports
the GSM850/900 bands and the other supports the DCS1800 and PCS1900 bands. Both PA
blocks share common power supply pins to distribute current. The GaAs die, the Silicon (Si)
die, and the passive components are mounted on a multi-layer laminate substrate. The
assembly is encapsulated with plastic overmold.
RF input and output ports of the SKY77324 are internally matched to a 50 Ω load to reduce
the number of external components for a quad-band design. Extremely low leakage current
(2.5 µA, typical) of the dual PA module maximizes handset standby time. The SKY77324 also
contains band-select switching circuitry to select GSM (logic 0) or DCS/PCS (logic 1) as
determined from the Band Select (BS) signal. In Figure 1, below, the BS pin selects the PA
output (DCS/PCS OUT or GSM850/900 OUT) and the Analog Power Control (VAPC) controls
the level of output power.
VBATT and VSENSE pins connect to an internal current-sense resistor and interface to an
integrated power amplifier control (iPAC™) function, which is insensitive to variations in
temperature, power supply, and process. The PAC ENABLE input allows initial turn-on of PAC
circuitry to minimize battery drain.
Figure 1. Functional Block Diagram
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [e-mail] • www.skyworksinc.com
103123C • Skyworks Proprietary and Confidential information. • Products and product information are subject to change without notice. • January 7, 2004
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