Adds frontend/src/data/examples-circuits.ts with 40 new examples organized
into 6 categories, each demonstrating a specific analog/digital/electromech
concept that the SPICE engine can simulate end-to-end:
PASSIVE / ANALOG (10):
voltage-divider, rc-low-pass-filter, wheatstone-bridge,
ntc-temperature, led-current-limiting, parallel-resistors,
pot-adc-reader, photoresistor-light, multi-led-bar,
capacitor-charge-curve
TRANSISTOR / SEMICONDUCTOR (8):
npn-led-switch, pnp-high-side-switch, mosfet-pwm-led,
diode-rectifier, zener-regulator, schottky-reverse-protection,
bjt-common-emitter, darlington-high-current
OP-AMP (5):
opamp-inverting, opamp-voltage-follower, opamp-comparator,
opamp-difference, opamp-schmitt-trigger
LOGIC GATES (6):
and-gate-alarm, xor-toggle-detector, nand-sr-latch,
full-adder, binary-counter-leds, logic-probe
ELECTROMECHANICAL (4):
relay-led-switch, optocoupler-signal,
l293d-motor-control, l293d-speed-pwm
POWER / REGULATOR (3):
power-supply-7805, lm317-adjustable-psu, battery-voltage-monitor
BOARD-SPECIFIC (4):
esp32-dual-adc, mega-multi-led, nano-sensor-station,
esp32-pwm-led-rgb (uses ESP32 LEDC peripheral)
The new examples are appended to exampleProjects[] in examples.ts so the
existing gallery and category filters pick them up automatically.
test/test_circuit/test/spice_examples.test.js validates each example's
analog topology in ngspice — 45 individual assertions covering all 40
examples (plus extra cases for NTC/Zener sweeps and L293D direction).
Sandbox tally: 164 -> 209 tests, 7.9s runtime, all green.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>