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NXP Semiconductors PCA96xx 2-wire Bus Switch & Output Port

NXP Semiconductors PCA96xx 2-wire Bus Switch & Output Port are monolithic CMOS integrated circuits for 2-wire bus interfaces, including I2C-bus, SMBus, PMBus, and other systems based on similar principles. The NXP Semiconductors PCA9646 Buffered 4-channel 2-wire Bus Switch has four outputs which may be independently enabled in any combination as determined by the contents of the programmable control register. Each I/O is impedance isolated from all others, thus allowing a total of five branches of 2-wire bus with the maximum specified load. The PCA9646 has excellent application to 2-wire bus address expansion and increasing of maximum load capacitance, such as in very large LED displays. 

The NXP Semiconductors PCA9621 8-bit 2-wire Bus Output Port has a 65mA sink capability, making it also ideal for driving LEDs. The state of the outputs is determined by a programmable 8-bit register which can be read and written via signals from the 2-wire bus. The 2-wire bus interface also has 30mA Fast-mode Plus (Fm+) capability, and consequently can be run in excess of 1MHz or up to 4000pF capacitance. As such, the PCA9621 can be connected to other 2-wire devices across long cable connections.

Features

  • Shared
    • Works with I2C-bus (Standard-mode, Fast-mode, and Fast-mode Plus (Fm+)), SMBus (standard and high power mode), and PMBus
    • Fast switching times allow operation in excess of 1MHz
    • Operating voltages from 2.7V to 5.5V
  • PCA9646 Switch Features & Benefits
    • Drop-in pin compatible with PCA9546A, etc.
    • Each I/O is impedance isolated from all others allowing maximum capacitance on all branches
    • 30mA static sink capability on all ports
    • Allows driving of large loads (e.g., 5 x 4nF)
    • Hysteresis on I/O increases noise immunity
  • PCA9621 Output Port Features & Benefits
    • 8 individually selectable open-drain output ports
    • 65mA static sink capability on all output ports
    • Ports may be paralleled for up to 500mA drive
    • Fast-mode Plus 2-wire bus capability

Applications

  • Large arrays of I2C-bus components, e.g., LED displays
  • Power management systems
  • Game consoles, computers, RAID systems
  • Simple high-power LED dimming
  • General purpose output
  • Instrumentation indicators

Datasheets

Published: 2011-12-12 | Updated: 2024-05-15