Thanks
@bary_t for this find.
It's quite unusual to see "_proto" revisions in production these days.
I didn't mention "mini_pez" in my post because I thought it was only an internal prototype.
Besides the Mini, there are multiple "pez" boards: rev4_pez_proto1, rev5_pez_proto1, rev5_pez_prod1, and rev5_pez_prod2.
What is "pez"?
It's a codename of the newest Starlink FEM chip, which will replace "panda".
The most distinctive feature of the new chip: active snow melt via FEM control bits. The new FEM supports two configuration parameters: snow_cb_idle and snow_cb_rx, which control PA biasing.
- In idle mode (snow melting): biases the FEM's PA stage for maximum heat dissipation rather than RF performance, turning the array elements into distributed heaters
- In receive mode: normal RX biasing with a residual snow-prevention bias offset
According to the board configuration, 120 out of 571 elements are designated as snow-melt-capable FEMs.
The snow_melt.trigs.low_snr.enabled = true, thres = 5.0 dB, t_cold = 35°C — snow melt activates when SNR drops below 5 dB, and PCB temperature is below 35°C.
It seems that the panel can zone heating to melt snow/evaporate water only where it's really necessary. This makes the system more energy efficient.
Previous versions of Starlink terminals for snow-melting were implemented using heater traces integrated into the PCB (rev1, rev2, HP versions) or by regulating overall power delivery to the entire panel (rev3, rev4, non-pez mini).
Interestingly, the new chip has the lowest EIRP of all: 29.48 dBm average (panda: 32.38 dBm average).
Also, it supports only 4 antenna elements (single port). Older FEMs support two ports with 8 antenna elements in total.