integrated circuits (ICs)
ICs (chips) are complete circuits etched onto tiny pieces of silicon and packaged so we can solder or plug them in. One chip can be a gate, a counter, an amplifier, a microcontroller… or an entire radio.
pins & orientation
Packages have a pin 1 mark (a dot) and/or a notch. Numbering goes counter-clockwise around the chip starting at pin 1.
holders (sockets)
- DIP sockets let you replace chips and avoid heat while soldering. Choose the same pin count and 0.3″ / 0.6″ width as your part.
- ICSP/ISP headers bring out programming pins for microcontrollers (handy while debugging).
- For SMD, use adapter boards (SOIC/TSSOP → DIP) when prototyping.
static (ESD)
- Touch ground before handling; avoid carpet + sweaters + dry air chaos.
- Keep chips in ESD bags/foam. Don’t rub pins.
- Power off before plugging/unplugging ICs or modules.
datasheets (what to read first)
- Pinout (names, power pins, enable pins).
- Absolute maximums vs recommended operating (never mix them up).
- Supply (VCC range), logic levels, and per-pin & per-package current.
- Timing (propagation delay, max clock), and any decoupling notes.
- Look for “typical application” schematics—gold for wiring.
source vs sink
Outputs can source current (provide it) or sink current (accept it to ground). Which one is stronger depends on the family—always check the sheet.
combining outputs (safely)
- Never tie two push-pull outputs together.
- To “OR” digital lines, use open-collector/open-drain outputs with a pull-up, or use diodes.
- Tri-state bus pins (OE) can share a line if only one talks at a time.
logic ICs
Small logic chips are building blocks: gates (AND/OR/NOT), flip-flops, counters, shift registers, multiplexers. See the 4000 series (wide voltage, slower) and 74 series (faster, 3.3–5 V families like HC/HCT).
PICs (microcontrollers)
PIC is Microchip’s microcontroller line (e.g., PIC16F, PIC18F). One chip can read pins, time things, blink LEDs, and talk over UART/I²C/SPI. You’ll need:
- a programmer (or on-board bootloader),
- power (often 2–5 V), decoupling caps, and sometimes a crystal,
- the datasheet (pin functions, configuration bits) or Microchip’s MCC tool.
Arduino-style boards hide setup, but learning from raw PIC/AVR/ARM teaches great habits.