Overview
The PCA9517ATP,147, manufactured by NXP USA Inc., is a CMOS integrated circuit designed as a level translating I²C-bus repeater. This device facilitates voltage level translation between low voltage (as low as 0.9 V) and higher voltage (2.7 V to 5.5 V) I²C-bus or SMBus applications. It retains all the operating modes and features of the I²C-bus system during level shifts, making it an essential component for extending and isolating I²C-bus segments.
Key Specifications
| Parameter | Conditions | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| VCC(B) supply voltage (port B) | 2.7 | 5.5 | V | ||
| VCC(A) supply voltage (port A) | 0.9 | 5.5 | V | ||
| ICC(VCC(A)) supply current on pin VCC(A) | 1 | mA | |||
| ICCH HIGH-level supply current both channels HIGH; VCC = 5.5 V; SDAn = SCLn = VCC | 1.5 | 5 | mA | ||
| Electrostatic discharge (HBM) | > 5.5 | kV |
Key Features
- Bidirectional buffering for both data (SDA) and clock (SCL) lines, enabling two buses of 400 pF each.
- Voltage level translation from 0.9 V to 5.5 V and from 2.7 V to 5.5 V.
- Footprint and functional replacement for PCA9515/15A.
- I²C-bus and SMBus compatible.
- Active HIGH repeater enable input.
- Open-drain input/outputs.
- Lock-up free operation.
- Supports arbitration and clock stretching across the repeater.
- Overvoltage tolerant inputs and I/Os up to 5.5 V even when the device is unpowered.
Applications
The PCA9517ATP,147 is suitable for various applications requiring I²C-bus or SMBus level translation and bus extension. These include:
- Embedded systems where different voltage levels are used.
- Industrial control systems requiring bus isolation and extension.
- Consumer electronics with mixed voltage domains.
- Automotive systems needing robust and reliable I²C-bus communication.
Q & A
- What is the primary function of the PCA9517ATP,147?
The PCA9517ATP,147 is a level translating I²C-bus repeater that provides voltage level translation between low voltage (down to 0.9 V) and higher voltage (2.7 V to 5.5 V) I²C-bus or SMBus applications.
- What are the supply voltage ranges for port A and port B?
Port A can operate from 0.9 V to 5.5 V, while port B operates from 2.7 V to 5.5 V.
- Can multiple PCA9517As be connected in series?
Yes, multiple PCA9517As can be connected in series from port A to port B without any build-up in offset voltage, only considering time of flight delays.
- What is the significance of the EN pin?
The EN pin is used to turn the drivers on and off under system control. It should only be changed when the bus is idle.
- Are the inputs and I/Os overvoltage tolerant?
Yes, all inputs and I/Os are overvoltage tolerant up to 5.5 V even when the device is unpowered.
- What is the maximum capacitance supported on each side of the device?
The device supports up to 400 pF on either side of the repeater.
- Is the PCA9517A compatible with SMBus?
Yes, the PCA9517A is compatible with both I²C-bus and SMBus).
- What is the electrostatic discharge (HBM) rating of the PCA9517A?
The PCA9517A has an electrostatic discharge (HBM) rating of more than 5.5 kV).
- Can the PCA9517A be used in a star topology configuration?
Yes, port A of two or more PCA9517As can be connected together to allow a star topology with port A on the common bus).
- Why should the PCA9517A be preferred over the PCA9517?
The PCA9517A is an improved version of the PCA9517 with enhanced hot swap and ESD capabilities, and it should be used for all new designs and system updates).
