electrical safety ~1 mA: OK ~10 mA: shock, contraction ~100 mA: fibrillation body: M ohm external, k ohm internal dielectric breakdown: ~kV/mm supply capacitors inductive flyback protection diodes connector polarization, orientation protection power USB supplies switching, linear, regulated supercapacitor batteries LiPo charge controller storage wireless current measurement supply regulation sense resistor magnetic field inductance RGB LED current limiting PWM hello.RGB.45 board components traces interior C makefile video pinouts pixels lights wires LEDs diode drop, series-parallel MOSFET N, P floating gates gate resistors BJT, BiCMOS, IGBT hello.LEDs.t412 board components traces interior hello.LEDs.t412.ino video thermal runaway eye safety LED array Charlieplexing hello.array.44 board components traces interior C makefile video hello.array.44.2 board components bottom vias top interior C makefile video displays LCD HD44780 library hello.LCD.44 board components traces interior C makefile video I2C PCF8574 library hello.I2C.t1614 hello.LCD.I2C.ino video OLED SSD1306 library library scripts pinout hello.SSD1306.45 board components traces interior C makefile video TFT ILI9341 library hello.ILI9341.SW.D21E board components traces interior video hello.ILI9341.HW.D21E board components top bottom holes interior video ST7735 video E Ink modules video RS170, NTSC, PAL, SECAM, VGA 75 ohm impedance hello.video.44 board components traces interior C makefile video SPI TVout thinner client color speaker DAC, PWM hello.speaker.45 board components traces interior C makefile video wavetable audio synthesis low-pass filter class D amplifier solenoid DC motor H-bridge A4950 TB67H451FNG,EL hello.H-bridge.44 board components traces interior C makefile video Dual H-bridge DRV8847 torque, power, efficiency, gearing vibration servo motor 50 Hz ~1-2 ms PWM (dis)continuous rotation ATtiny412 hello.servo.t412 board components traces interior hello.servo.t412.ino hello.servo-registers.t412.ino video ATSAMD11C hello.servo-D11C board traces interior Gerber top copper solder mask silkscreen outline ATtiny44 hello.servo.44 board components traces interior ZLDO1117 hello.servo.44.1 board components traces interior LM2940 C (hardware PWM) makefile C (two-channel, software PWM) makefile video brushless DC motor (BLDC) efficiency, density, reliability, noise inrunner, outrunner, pancake, fan Kv (RPM/V) ~1,10,100,1000 A,$ triple half-bridge DRV11873 drive waveform open-loop, closed-loop control back EMF (BEMF) sensing electronic speed controller (ESC) hello.ESC.44 board components traces interior C makefile video firmware servo PWM initialization, calibration stepper motor types wire identification step PWM, duration microstepping step and direction DRV8428 hello.DRV8428 board components traces interior hello.DRV8428.ino video hello.DRV8428-D11C-NEMA17 board components traces holes interior Gerber top copper solder mask silkscreen outline hello.DRV8428-D11C board components traces holes interior hello.DRV8428-D11C.ino video DVR8428P DRV8436 bipolar H-bridge hello.stepper.bipolar.44 board components traces interior full makefile video unipolar NMOSFET hello.stepper.44 board components traces interior wave makefile full makefile half makefile video electro-permanent motor control Allegro TI Trinamic Pololu TinyG RAMPS Mechaduino nRF52 DDMC solid state relay AC vs DC IC hockey puck wiring voltage drop: ~V safety: switch hot side US: black (red,blue) = hot, white = neutral, green(-yellow) = ground EU: brown (black,gray) = hot, blue = neutral, green-yellow = ground switched outlet shape memory piezo polymer artificial muscle fishing line conducting thread actuator soft inflatable pneumatics hydraulics assignment individual assignment: add an output device to a microcontroller board you've designed, and program it to do something group assignment: measure the power consumption of an output device