RFFM4201 Datasheet, PDF (6/14 Pages) RF Micro Devices – 3.3V TO 5V, 2.4GHz TO 2.5GHz HIGH POWER FRONT END MODULE

RFFM4201
General Layout Guidelines and Considerations:
For best performance the following layout guidelines and considerations must be followed regardless of final use or configura-
tion:
1. The ground pad of the RFFM4201 has special electrical and thermal grounding requirements. This pad is the main RF
ground and main thermal conduit path for heat dissipation. The GND pad and vias pattern and size used on the RFMD eval-
uation board should be replicated. The RFMD layout files in Gerber format can be provided upon request. Ground paths
(under device) should be made as short as possible.
2. The RF lines should be well separated with solid ground in between the traces to eliminate any possible RF leakages or
cross-talking.
3. Bypass capacitors should be used on the DC supply lines. The VCC lines may be connected after the RF bypass and decou-
pling capacitors to provide better isolation between each VCC line.
RFFM4201 Tx Production and System Calibration Recommendation:
It is highly recommended to follow the DC biasing step and RF power settings in the production calibration or test.
1. Connect the RF cables of input and output then connect to the proper equipment.
2. Apply V_CC, then V_REG as per the data sheet recommendations.
3. Set RF input to the desired frequency and initial RF input power at -20dBm. This will insure the power amplifier is in a linear
state and not over driven.
4. Set FEM in Tx mode by the truth table.
5. Apply P_DOWN = high
6. Sweep RF from low to high output power and take measurements at the rated output power.
7. Ensure that the output power at turn on does not saturate the power amplifier. The recommended output power should be
about 10dB to 20dB below the rated power. Start calibrating from low to high power in reasonable steps until the rated
power is reached then take the measurements.
CAUTION: If the input signal exceeds the maximum input power specifications, the RFFM4201 could be permanently dam-
aged.
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7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical
support, contact RFMD at ([phone] or [e-mail].
DS121008