Overview
The PCA9515ADRGR, produced by Texas Instruments, is a dual bidirectional I2C bus and SMBus repeater. This component is designed to isolate two halves of an I2C or SMBus, allowing for the connection of more devices or the extension of bus trace lengths. It buffers both the serial data (SDA) and serial clock (SCL) signals, retaining all operating modes and features of the I2C system. This repeater is particularly useful in systems where bus capacitance needs to be managed or where longer bus lengths are required.
Key Specifications
| Parameter | Description |
|---|---|
| Package Type | SOIC (8) 4.90 mm × 3.91 mm, SON (8) 3.00 mm × 3.00 mm |
| Bus Compatibility | I2C Bus and SMBus Compatible |
| Operating Modes | Standard Mode and Fast Mode I2C, SMBus |
| Bus Capacitance | Up to 400 pF per bus |
| Supply Voltage | 2.3 V to 5.5 V |
| Propagation Delay | Typically around 160 ns for SCL and SDA signals |
| Output Configuration | Open-collector configuration |
| Power-Up Control | Internal latch to prevent output circuits from becoming active until VCC is at a valid level |
Key Features
- Buffers both SDA and SCL signals to extend bus length and increase the number of devices on the bus.
- Supports Standard Mode and Fast Mode I2C devices, as well as SMBus devices.
- Open-collector configuration for output signals.
- Internal power-up control circuit to prevent output circuits from becoming active until VCC is at a valid level.
- Requires pullup resistors on each side of the repeater to provide logic high levels.
- Avoids lockup conditions between input and output of each repeater through slightly different valid low-voltage levels.
Applications
- Extending I2C or SMBus trace lengths in complex systems.
- Increasing the number of devices on an I2C or SMBus.
- Isolating different segments of an I2C or SMBus to manage bus capacitance and improve signal integrity.
- Use in systems requiring reliable and robust I2C or SMBus communication, such as industrial control systems, automotive systems, and consumer electronics.
Q & A
- What is the primary function of the PCA9515ADRGR?
The PCA9515ADRGR is a dual bidirectional I2C bus and SMBus repeater designed to buffer SDA and SCL signals, allowing for the extension of bus lengths and the connection of more devices.
- Which I2C modes does the PCA9515ADRGR support?
The PCA9515ADRGR supports both Standard Mode and Fast Mode I2C devices, as well as SMBus devices.
- What is the maximum bus capacitance supported by the PCA9515ADRGR?
The PCA9515ADRGR can support up to 400 pF of bus capacitance per bus.
- Why are pullup resistors required for the PCA9515ADRGR?
Pullup resistors are required on each side of the repeater to provide the necessary logic high levels for the I2C or SMBus signals.
- How does the PCA9515ADRGR prevent lockup conditions?
The PCA9515ADRGR uses slightly different valid low-voltage levels to avoid lockup conditions between the input and output of each repeater.
- What is the purpose of the internal power-up control circuit in the PCA9515ADRGR?
The internal power-up control circuit sets an internal latch to prevent the output circuits from becoming active until VCC is at a valid level.
- Is the PCA9515ADRGR still in production?
No, the PCA9515ADRGR is obsolete and no longer manufactured by Texas Instruments.
- What are some common applications for the PCA9515ADRGR?
Common applications include extending I2C or SMBus trace lengths, increasing the number of devices on a bus, and isolating different segments of a bus to manage capacitance and improve signal integrity.
- How does the PCA9515ADRGR handle clock stretching?
The PCA9515ADRGR does not support clock stretching, which is a feature available in the PCA9515B model.
- What are the package options for the PCA9515ADRGR?
The PCA9515ADRGR is available in SOIC (8) and SON (8) packages.
