APA102
APA102 — The High-Speed Alternative
The APA102 is a 2-wire SPI addressable LED that offers significant advantages over NRZ-based chips like WS2812B — at a slightly higher cost.
Specifications
| Parameter | Value |
|---|---|
| Voltage | 5V DC |
| Current | ~60mA per LED (full white) |
| Protocol | 2-wire SPI (clock + data) |
| Refresh rate | ~2-20 kHz (depends on clock speed) |
| Color depth | 24-bit + 5-bit global brightness |
| Data rate | Up to 20 MHz |
| Max chain | Limited by clock timing, ~2000+ feasible |
Key Advantages Over WS2812B
- 2-wire SPI — No strict timing requirements
- Global brightness — 5-bit (32 levels) independent of color data
- High refresh — 2kHz+ means no flicker on camera
- No timing issues — Works on any platform with SPI
- Daisy-chainable — Clock sync means longer chains
Best Uses
- Film/TV lighting (flicker-free)
- Video-synced installations
- Long chains with high frame rates
- Projects on non-Arduino platforms (Raspberry Pi, etc.)
- When budget allows slightly more expensive strips
Comparison with SK9822
The SK9822 is an APA102 clone with slightly different timing. Most implementations treat them identically.
| Feature | APA102 | SK9822 |
|---|---|---|
| Start frame | 32-bit zero | 32-bit zero |
| End frame | 32-bit one | 32-bit one |
| Global brightness | 5-bit | 5-bit |
| Timing | Standard | Slightly different |
| Price | ~$0.10-0.20/LED | ~$0.08-0.15/LED |