| commit | b1bd19506a0d71cab82951fd5de8c7d5dd1a220f | [log] [tgz] |
|---|---|---|
| author | yrrapt <yrrapt@gmail.com> | Fri Dec 18 20:32:19 2020 +0100 |
| committer | yrrapt <yrrapt@gmail.com> | Fri Dec 18 20:32:19 2020 +0100 |
| tree | d36b8674c6c78073b3b3137a315a8435d7c6e94c | |
| parent | 93eb59769060f31bdd0bd8cb5f091dbee2254423 [diff] |
updated documentation
This is the Google/EFabless/Skywater Caravel submission of the Amateur Radio Satellite Transceiver.
These blocks serve as the first pieces in a larger design of an open source amateur radio satellite transceiver - this is the first tapeout submission.
The design sources of the continued project can be found here: amsat_txrx_ic.
A S-Band phase locked loop employing a differential ring oscillator VCO with quadrature outputs. CML (Current Mode Logic) and flip-flop based pre-scaler dividers are used with a fractional-N divider which uses a 3rd order MASH structure with dithering. Finally a PFD (Phase Frequency Detector) is combined with a charge pump with off chip filtering to complete the loop.
A cell based buffer is used to drive the external 100 ohm differential output.
A bandgap reference with separate PTAT and CTAT currents. Provides less than variation from -40 to 125 degrees celcius. 6 bits of trimming on both PTAT and CTAT allows less than 1% accuracy over process variations.
To install the environment used for development of this repository, follow these instructions.
git clone https://github.com/yrrapt/sky130_setup.git cd sky130_setup ./install_pdk.sh ./install_tools.sh
cd amsat_txrx_ic-caravel/xschem xschem
cd amsat_txrx_ic-caravel/gds klayout amsat_txrx_ic-caravel.gds
cd amsat_txrx_ic-caravel/utils ./run_drc amsat_txrx_ic-caravel
cd amsat_txrx_ic-caravel/utils ./run_drc amsat_txrx_ic-caravel
