Overview
The TCA9517DGKRQ1, produced by Texas Instruments, is a level-shifting I2C bus repeater designed to extend I2C and SMBus systems without degrading performance. This device is particularly useful in mixed-mode applications where voltage-level translation is necessary between low voltages (down to 0.9 V) and higher voltages (2.7 V to 5.5 V). The TCA9517-Q1 buffers both the serial data (SDA) and the serial clock (SCL) signals, enabling the connection of two buses with up to 400-pF bus capacitance each.
Key Specifications
| Parameter | Value |
|---|---|
| Package | VSSOP (8-pin) |
| Body Size | 3.00 mm × 3.00 mm |
| Operating Supply Voltage Range (A-side) | 0.9 V to 5.25 V |
| Operating Supply Voltage Range (B-side) | 2.7 V to 5.5 V |
| Bus Capacitance | Up to 400 pF per bus |
| Maximum Operating Frequency | Up to 400 kHz |
| Input/Output Voltage Tolerance | Up to 5.5 V (unpowered) |
| Temperature Grade | Automotive |
Key Features
- Bidirectional level-shifting capabilities for I2C and SMBus systems.
- Supports standard and fast mode I2C operations.
- Active-high repeater-enable input (EN) with internal pull-up to VCCB.
- Clock stretching support with careful pull-up resistor selection.
- Overvoltage tolerant inputs and I/Os up to 5.5 V, even when unpowered.
- Ability to connect multiple devices in series (A-side to B-side) without offset voltage buildup.
Applications
The TCA9517DGKRQ1 is suitable for various applications requiring I2C or SMBus bus extension and level shifting, such as:
- Mixed-mode systems where different voltage levels are used.
- Automotive systems due to its automotive temperature grade.
- Industrial control systems where bus extension is necessary.
- Consumer electronics requiring reliable I2C/SMBus communication.
Q & A
- What is the primary function of the TCA9517DGKRQ1?
The primary function is to act as a level-shifting I2C bus repeater, enabling the connection of two I2C buses with different voltage levels. - What are the operating voltage ranges for the A-side and B-side drivers?
The A-side drivers operate from 0.9 V to 5.25 V, and the B-side drivers operate from 2.7 V to 5.5 V. - Can multiple TCA9517-Q1 devices be connected in series?
Yes, multiple devices can be connected in series from A-side to B-side without offset voltage buildup. - What is the maximum bus capacitance supported by the TCA9517-Q1?
The device supports up to 400 pF bus capacitance per bus. - Does the TCA9517-Q1 support clock stretching?
Yes, it supports clock stretching, but careful selection of pull-up resistors is necessary to minimize overshoot voltage. - What is the purpose of the active-high enable (EN) input?
The active-high enable input allows the user to select when the repeater is active and can be used to isolate a badly behaved slave on power-up reset. - Is the TCA9517-Q1 overvoltage tolerant?
Yes, all inputs and I/Os are overvoltage tolerant up to 5.5 V, even when the device is unpowered. - What are the typical applications for the TCA9517-Q1?
It is used in mixed-mode systems, automotive systems, industrial control systems, and consumer electronics requiring reliable I2C/SMBus communication. - What is the maximum operating frequency of the TCA9517-Q1?
The device supports up to 400 kHz operating frequency. - Can the B-side of two TCA9517-Q1 devices be connected directly?
No, the B-side of two devices cannot be connected directly due to the buffered low voltage feature.
