BrightNova & CircuitSage
BrightNova BrightNova
CircuitSage CircuitSage
BrightNova BrightNova
Hey CircuitSage, I've been toying with the idea of a self‑diagnosing micro‑probe for deep space missions—imagine a tiny satellite that can label its own faults and fix them in real time. Want to help me sketch out a diagnostic circuit for the power system?
CircuitSage CircuitSage
Sure, here’s a quick schematic outline. - Power input: VBUS (5 V) from solar cells - Bulk capacitor: C1 (100 µF) at VBUS-GND - Main regulator: U1 (buck, 3.3 V) – outputs VREG, returns VOUT - Current sense: R1 (0.1 Ω) on VOUT to sense IOUT → A1 (amplifier) → ADC0 - Voltage sense: R2 (10 kΩ) divider on VOUT → ADC1 - Fault thresholds: F1 (over‑current, >1 A), F2 (over‑voltage, >3.6 V), F3 (under‑voltage, <2.8 V) - Comparator: U2 (±1 V) checks ADC0 against F1, ADC1 against F2/F3 → fault flags F_F1, F_F2, F_F3 - Self‑reset logic: MCU (ATmega) reads fault flags, writes to EEPROM label L_Fault with timestamp, then toggles MOSFET FET1 to shut off VBUS for 0.5 s, then restarts U1. - Diagnostic bus: CAN‑FD interface at VREG for telemetry. Label every component, keep wiring tidy, and you’ve got a self‑diagnosing power block.
BrightNova BrightNova
Nice rundown, CircuitSage! That layout already screams reliability—just make sure the MOSFET gate drive is fast enough to snap the VBUS off before the regulator latches. We can bump the bulk cap to 200 µF for extra stability during the reset pulse. Also, let’s add a small RC snubber across the MOSFET to tame any ringing when you shut it down. Ready to sketch the PCB?
CircuitSage CircuitSage
Absolutely, let’s line everything up. I’ll draft the board with a 200 µF bulk cap next to the MOSFET, label the snubber as S1, and keep the gate driver close to the FET to keep the rise time under 50 ns. Once I send the Gerber files, we’ll see if the layout matches the diagram.
BrightNova BrightNova
That’s the spirit—tight layout and snubbers always keep the ripple in check. Just double‑check the thermal spread on the MOSFET; a small copper pour there will keep it cool during the shutdown pulses. Once you hit send, I’ll run through a quick virtual simulation before we hit the fabricator. Bring those Gerbers, and let’s get this block blasting into space!
CircuitSage CircuitSage
Will do, adding a copper pour around the MOSFET for heat spread. Gerbers coming your way in the next hour, ready for the simulation. Let me know if you spot any issues before we send them out.