مخطط الأطراف
مخطط أطراف موسّع المنافذ PCF8574 عبر I2C (DIP-16)
الأطراف
- 1–3 A0–A2 (address select: 0x20–0x27; PCF8574A: 0x38–0x3F)
- 4–7 P0–P3 and 9–12 P4–P7 (8 quasi-bidirectional I/O, weak internal pull-ups)
- 8 VSS (GND), 16 VDD (2.5–6V)
- 13 INT (interrupt out, active low — fires on any input change)
- 14 SCL, 15 SDA
- The chip on every I2C LCD backpack
المواصفات
| جهد التغذية | 2.5–6 V |
|---|---|
| الواجهة | I2C, 100 kHz (standard mode) |
| I2C address | PCF8574: 0x20–0x27; PCF8574A: 0x38–0x3F (set by A0–A2) |
| I/O | 8 quasi-bidirectional pins |
| Output sink current | 25 mA max per pin (100 mA total) |
| Output source current | Weak: ≈ 100 µA typ pull-up — drive LEDs by sinking |
| Standby current | ≈ 2.5 µA typ, 10 µA max |
| Interrupt | Open-drain INT, active low, on any input change |
| Operating temperature | −40–85 °C |
| الغلاف | DIP-16, SOIC-16, TSSOP-20 |
