SLVAFN4 October 2023 TCA9509 , TCA9517A
While the TCA9509 can be used to resolve invalid implementation of static voltage offsets on I2C buffers, there are several considerations that need to be made as well. The TCA9509 can only support I2C operations up to 400 kHz, meaning if the system requires a higher data rate, this device can not be used. Since the SVO feature is on the A-side of the device, system designers need to be aware that pullup resistors and series resistors on this side need to be removed to allow VILC to be satisfied. The internal structure of the device also does not have an internal pull-up on the OE pin like the TCA9617A/B, so an external pull-up can be required. Furthermore, translation applications from one voltage to another with this device requires VCCA to be at least 1 V less than VCCB. The key differences between the I2C buffers with SVO can be found in Table 3-1.
| Device | TCA9517 | TCA9517A | TCA9617A/B | TCA9509 |
|---|---|---|---|---|
| Static Voltage Offset Side | B | B | B | A |
| Supported VCC Range |
VCCA: 0.9 to 5.5 VCCB: 2.7 to 5.5 |
VCCA: 0.9 to 5.5 VCCB: 2.7 to 5.5 |
VCCA: 0.8 to VCCB VCCB: 2.2 to 5.5 |
VCCA: 0.9 to 5.5 VCCB: 2.7 to 5.5 |
| VOL | 0.45 to 0.6 V (B-side) | 0.45 to 0.6 V (B-side) | 0.48 to 0.58 V (B-side) | 0.2 V (A-side) |
| VILC | 0.4 V | 0.45 V | 0.4 V | 0.15 V |
| VIL(max) Non offset side | 0.3 × VCCA | 0.3 × VCCA | 0.3 × VCCA | 0.3 × VCCB |
| Max data rate | 400 kHz | 400 kHz | 1 MHz | 400 kHz |
| Package options | VSSOP(8), SOIC(8) | VSSOP (8) | VSSOP (8) | VSSOP (8), X2QFN(8) |
| P2P | Y | Y | Y | Y |