The Skyworks SKY65116 is a fully matched, 12-pin, 8 x 8 mm2, surface mount multi-chip module (MCM), linear Power Amplifier (PA), high linearity and high efficiency surface mount module designed for use in the 390–500 MHz band.
The device is fabricated using Skyworks high reliability Gallium Arsenide (GaAs) Heterojunction Bipolar Transistor (HBT) process, which allows for single supply operation while maintaining high efficiency and good linearity. Microwave Monolithic Integrated Circuits (MMICs), comprised of GaAs and Silicon CMOS, contain 020all the active circuitry in the module. This includes the in-module bias circuitry, as well as the RF interstage matching circuit. The input and output match is realized off-chip within the module package to optimize efficiency and high power performance (P1 dB = 32.5 dBm) into a 50 W load.
Primary bias to the SKY65116 can be supplied directly from a single cell lithium-ion or other suitable battery with a nominal output of 3.6 V. No external supply side switch is needed as typical “off” leakage is a few microamperes with full primary voltage supplied from the battery.
The module can operate over the temperature range of -40 °C to +85 °C. A populated evaluation board is available upon request.
- TETRA radio
- GSM450 and GSM480
- Wireless local loop
- UHF TV broadcast
- Wideband frequency operation: 390–500 MHz
- High linearity: OIP3 43 dBm
- High efficiency: 40% PAE
- High gain: 35 dB
- P1 dB = 32.5 dBm
- Single DC supply: 3.6 V
- Internal RF match and bias circuits
- PA on/off voltage control
- Operating temperature -40 °C to +85 °C
- Available on tape and reel
- Low cost MCM 12-pin (8 x 8 mm) package
- Available lead (Pb)-free and RoHS-compliant MSL-3, 260 °C per JEDEC J-STD-020
Theory of Operation
The SKY65116 is comprised of two amplifier stages, and is internally matched for optimum linearity and efficiency. The matching circuits for the input stage, inter-stage, and output stage are contained within the device. An on-chip active bias circuit is included within the device for both input and output stages providing for excellent gain tracking over temperature and voltage variations. The module operates with all positive DC voltages while maintaining high efficiency and good linearity. The nominal operating voltage is 3.6 V for maximum power, but can be operated at slightly lower voltages for other mobile applications.
The input and output stages are independently supplied using the VCC1 and VCC2 supply lines, pins 4 and 10, respectively. The bias reference voltage is supplied using a common VREF (pin 12) line.
The module includes a silicon CMOS controller circuit to provide an amplifier On/Off operation. VCNT (pin 11) is the PA on/off control voltage to the CMOS controller for stages 1 and 2. 0 V = Off, 3.6 V = On. Nominal “On” operating range is between 2.7 to 3.6 VDC. VCNT set to 0 VDC will force the amplifier into off mode, drawing only microamperes of current.
Application Circuit Notes
Center Ground. It is extremely important that the device paddle be sufficiently grounded for both thermal and stability reasons. Multiple small vias are acceptable and will work well under the device if solder migration is an issue.
Ground (Pins 1, 3, 5, 6, 7, 9). Attach all ground pins to the RF ground plane with the largest diameter and lowest inductance via that the layout will allow. Multiple small vias are also acceptable and will work well under the device if solder migration is an issue.
RF_IN (Pin 2). Amplifier RF Input Pin. ZO = 50 W. The module includes an onboard internal DC blocking capacitor. All impedance matching is provided internal to the module.
VCC1 (Pin 4). Supply voltage for the first stage collector bias (typically 3.6 V). Bypassing of VCC1 is accomplished with C7 and C8 and should be placed in the approximate location shown on the evaluation board, but placement is not critical.
RF_OUT (Pin 8). Amplifier RF Output Pin. ZO = 50 W. The module includes an onboard internal DC blocking capacitor. All impedance matching is provided internal to the module.
VCC2 (Pin 10). Supply voltage for the output (final) stage collector bias (typically 3.6 V). Bypassing of VCC2 is accomplished with C1 and C4 and should be placed in the approximate location shown on the evaluation board, but placement is not critical.
VCNT (Pin 11).VCNT is the PA on/off control voltage to the silicon CMOS controller for stages 1 and 2. 0 V = Off, 3.6 V = On. Nominal “On” operating range is between 2.7 to 3.6 VDC. VCNT set to 0 VDC will force the amplifier into standby mode.
VREF (Pin 12). Bias reference voltage for amplifier stages 1 and 2. VREF should be operated over the same voltage range as VCC, with a nominal voltage of 3.6 V.
Package and Handling Information
Since the device package is sensitive to moisture absorption, it is baked and vacuum packed before shipping. Instructions on the shipping container label regarding exposure to moisture after the container seal is broken must be followed. Otherwise, problems related to moisture absorption may occur when the part is subjected to high temperature during solder assembly.
Please refer to Skyworks solder reflow application note, available at www.skyworksinc.com, for instructions on mounting the SKY65116 to a printed circuit board.
Production quantities of this product are shipped in a standard tape and reel format. For packaging details, refer to the Skyworks Application Note, Tape and Reel, document number 101568.
Electrostatic Discharge (ESD) Sensitivity
The SKY65116 is a static-sensitive electronic device. Do not operate or store near strong electrostatic fields. Take proper ESD precautions.
Evaluation Board Description
The Skyworks SKY65116 evaluation board is used to test the performance of the SKY65116 power amplifier module. The following design considerations are general in nature and must be followed regardless of final use or configuration.
1. Paths to ground should be made as short as possible.
2. The ground pad of the SKY65116 power amplifier module has special electrical and thermal grounding requirements. This pad is the main thermal conduit for heat dissipation. Since the circuit board acts as the heat sink, it must shunt as much heat as possible from the amplifiers. As such, design the connection to the ground pad to dissipate the maximum wattage produced to the circuit. Multiple vias to the grounding layer are required.
3. Two external output bypass capacitors (0.01 μF and 10 μF) are required on the VCC1 (pin 4) supply input. The same two capacitor values are also required on the VCC2 (pin 10) supply input and on the VREF input (pin 12). Each of these capacitors should be placed in parallel between the supply line and ground.
4. VCC1 (pin 4) and VCC2 (pin 10) may be connected together at the supply.
Evaluation Board Test Procedure
Use the following procedure to set up the SKY65116 evaluation board for testing:
1. Connect a 3.6 V supply to VCC1 and VCC2, and 3.6 V supply to VREF and VCNT. If available, enable the current limiting function of the VCC power supply to 1.5 A.
2. Connect a signal generator to the RF signal input port. Set it to the desired RF frequency at a power level of 2 dBm or less to the evaluation board but do NOT enable the RF signal.
3. Connect a spectrum analyzer to the RF signal output port.
4. Enable the power supply.
5. Enable the RF signal.