commit | a1c73a2019bcf9f50142c21f5fdf3a3b53a2b689 | [log] [tgz] |
---|---|---|
author | yrrapt <yrrapt@gmail.com> | Fri Dec 18 22:57:00 2020 +0100 |
committer | yrrapt <yrrapt@gmail.com> | Fri Dec 18 22:57:00 2020 +0100 |
tree | be431a2a430f6cc067fc5e044eb0b52d61f26913 | |
parent | 24010f28a1d75992585bbf1ee97d8f1a099d3b96 [diff] | |
parent | df247719963785ae90c3dc60ae70378cd858fa1b [diff] |
Merge branch 'master' of https://github.com/yrrapt/caravel_amsat_txrx_ic
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.
VCO Layout
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.
Bandgap Layout
A bandgap reference with separate PTAT and CTAT currents. Provides less than +/-0.2% variation from -40 to 125 degrees celcius (tt simulation). 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