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Manufacturer Part #


PCA9509 Series Level translating I2C-bus/SMBus repeater - TSSOP - 8

ECAD Model:
Mfr. Name: NXP
Standard Pkg:
Product Variant Information section
Date Code: 2108
Product Specification Section
Technical Attributes
Attributes Table
Interface Circuit Type: I2C/SMBus
No of Channels: 2
Clock Frequency-Max: 400kHz
Supply Voltage-Nom: 3V to 5.5V
Supply Current: 0.25mA to 5mA
Package Style:  TSSOP-8
Mounting Method: Surface Mount
Features & Applications
The PCA9509 is a level translating I2C-bus/SMBus repeater that enables processor low voltage 2-wire serial bus to interface with standard I2C-bus or SMBus I/O. While retaining all the operating modes and features of the I2C-bus system during the level shifts, it also permits extension of the I2C-bus by providing bidirectional buffering for both the data (SDA) and the clock (SCL) lines, thus enabling the I2C-bus or SMBus maximum capacitance of 400 pF on the higher voltage side. Port A allows a voltage range from 1.0 V (as low as 0.95 V in special cases) to VCC(B) - 1.0 V and requires no external pull-up resistors due to the internal current source. Port B allows a voltage range from 3.0 V to 5.5 V and is overvoltage tolerant. Both port A and port B SDA and SCL pins are high-impedance when the PCA9509 is unpowered.


  • Bidirectional buffer isolates capacitance and allows 400 pF on port B of the device
  • Voltage level translation from port A (1 V [0.95 V in special cases] to VCC(B) - 1.0 V) to port B (3.0 V to 5.5 V)
  • Requires no external pull-up resistors on lower voltage port A
  • Active HIGH repeater enable input
  • Open-drain inputs/outputs
  • Lock-up free operation
  • Supports arbitration and clock stretching across the repeater
  • Accommodates Standard-mode and Fast-mode I2C-bus devices and multiple masters
  • Powered-off high-impedance I2C-bus pins



Pricing Section
Global Stock:
Factory Stock:Factory Stock:
Factory Lead Time:
52 Weeks
Minimum Order:
Multiple Of:
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Web Price
Product Variant Information section