@@ -200,6 +200,10 @@ When all of these dried, it turned out that only the black pigment adhered to th
**Making a transistor circuit**
Transistorrrrs! We're using an N-channel Mosfet transistor here this week to open and close the power flow to a high power actuator such as a heating pad or motor. With this you can power the IC at a lower voltage and use the IC's brain to control when higher power from a separate secondary power source flows to the actuator. This way you can power devices that need a different operating voltage within one control circuit.
We have a box of transistors here but I found out it's a mix of Voltage Regulators and Mosfets, they don't exactly do the same thing so I had to look at a lot of tiny numbers to find an N-channel MOSFET. I have a IRF530 here, that can control 100V-14A and the pinouts are the same as the example. Gate, Drain, Source from left to right when viewing it from the top.
I added a 1N4007 diode (1000V-1A) for safety in case I want to use it with motors etc at a later stage. Never hurts to protect a circuit. I used this one because it's what I had in my box of stuff, but didn't have the 1N4001 (50V - 1A) Liza suggested. Emma wasn't sure why Liza would put a diode in series to one of the leads, instead of in parallel across the leads. We asked Liza and she said [...]
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*Swatch with a conductive alum crystal as capacitive touch sensor, fading an LED, Loes Bogers, 2019*
## References for further reading
Liza suggested browsing the student documentation done for Tom Igoe's Physical Computing ITP class at NYU. Indeed, really amaaaaazing work, wow! Scroll down the pages to see links to student work:
