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RF Building Blocks: Mixers and PLLs - TikZ Figures

RF signal chain: a transmitter up-converts baseband/IF to RF before the power amplifier; a receiver amplifies, down-converts to a fixed IF/baseband and detects
Fig: RF signal chain: a transmitter up-converts baseband/IF to RF before the power amplifier; a receiver amplifies, down-converts to a fixed IF/baseband and detects
Up-conversion (IF\,\,RF) selects the sum product; down-conversion (RF\,\,IF) selects the difference product. The same mixer core serves both directions
Fig: Up-conversion (IF\,\,RF) selects the sum product; down-conversion (RF\,\,IF) selects the difference product. The same mixer core serves both directions
Mixer frequency conversion: f_RF and f_LO multiply to give f_IF=f_RF-f_LO (selected) plus the sum, while an image on the opposite side of the LO maps to the same IF
Fig: Mixer frequency conversion: f_RF and f_LO multiply to give f_IF=f_RF-f_LO (selected) plus the sum, while an image on the opposite side of the LO maps to the same IF
Mixer classification: passive diode/FET topologies (single-ended, single-balanced, double-balanced/ring) versus active transistor mixers such as the Gilbert cell
Fig: Mixer classification: passive diode/FET topologies (single-ended, single-balanced, double-balanced/ring) versus active transistor mixers such as the Gilbert cell
PLL core: the phase detector (PD) compares reference and feedback phase; the loop filter averages the error; the VCO output is fed back (optionally N) to close the loop
Fig: PLL core: the phase detector (PD) compares reference and feedback phase; the loop filter averages the error; the VCO output is fed back (optionally N) to close the loop
The capture range (acquire lock from unlocked) is nested inside the wider lock/hold range (stay locked as the input drifts)
Fig: The capture range (acquire lock from unlocked) is nested inside the wider lock/hold range (stay locked as the input drifts)
PLL applications span demodulation, synchronization, frequency synthesis and automatic frequency control
Fig: PLL applications span demodulation, synchronization, frequency synthesis and automatic frequency control
PLL as an FM demodulator: the recovered message is taken as the loop-filter control voltage that forces the VCO to follow the input
Fig: PLL as an FM demodulator: the recovered message is taken as the loop-filter control voltage that forces the VCO to follow the input
Integer-N frequency synthesizer: reference R, PFD, loop filter, VCO and N feedback give f_out=(N/R)\,f_xtal
Fig: Integer-N frequency synthesizer: reference R, PFD, loop filter, VCO and N feedback give f_out=(N/R)\,f_xtal