74HC245 Octal Bus Transceiver with 3-State Outputs
Octal bidirectional bus transceiver with 3-state outputs. DIR controls data direction (HIGH = A→B, LOW = B→A). ~OE (Active Low) disables all outputs to high-impedance. Widely used for 3.3V↔5V level translation.
Aliase:SN74HC245N, 74HCT245, Octal Transceiver, Level Shifter
DIP-20 Top View
20 Pins
Pinout Table20
| Pin | Signal / Name | Type | Alternative Functions |
|---|---|---|---|
| 1 | DIR | Digital | Direction Control (HIGH = A→B, LOW = B→A) |
| 2 | A0 | Digital | Bus I/O Port A, Bit 0 |
| 3 | A1 | Digital | Bus I/O Port A, Bit 1 |
| 4 | A2 | Digital | Bus I/O Port A, Bit 2 |
| 5 | A3 | Digital | Bus I/O Port A, Bit 3 |
| 6 | A4 | Digital | Bus I/O Port A, Bit 4 |
| 7 | A5 | Digital | Bus I/O Port A, Bit 5 |
| 8 | A6 | Digital | Bus I/O Port A, Bit 6 |
| 9 | A7 | Digital | Bus I/O Port A, Bit 7 |
| 10 | GND | Ground | System Ground (0V) |
| 11 | B7 | Digital | Bus I/O Port B, Bit 7 |
| 12 | B6 | Digital | Bus I/O Port B, Bit 6 |
| 13 | B5 | Digital | Bus I/O Port B, Bit 5 |
| 14 | B4 | Digital | Bus I/O Port B, Bit 4 |
| 15 | B3 | Digital | Bus I/O Port B, Bit 3 |
| 16 | B2 | Digital | Bus I/O Port B, Bit 2 |
| 17 | B1 | Digital | Bus I/O Port B, Bit 1 |
| 18 | B0 | Digital | Bus I/O Port B, Bit 0 |
| 19 | ~OE | Digital | Output Enable (Active Low — pull LOW to enable; HIGH = all outputs Hi-Z) |
| 20 | VCC | Power | Positive Power Supply (2–6V) |