Low-Voltage Translating, 8-Bit I²C-Bus/SMBus I/O Expander

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Product Details

Block Diagram

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PCAL6408A Block Diagram

PCAL6408A Block Diagram

PCA2000/2001 Block Diagram

PCA2000/2001 Block Diagram


Key Features

  • I²C-bus to parallel port expander
  • Operating power supply voltage range of 1.65 V to 5.5 V
  • Allows bidirectional voltage-level translation and GPIO expansion between:
    • 1.8 V SCL/SDA and 1.8 V, 2.5 V, 3.3 V or 5 V Port P
    • 2.5 V SCL/SDA and 1.8 V, 2.5 V, 3.3 V or 5 V Port P
    • 3.3 V SCL/SDA and 1.8 V, 2.5 V, 3.3 V or 5 V Port P
    • 5 V SCL/SDA and 1.8 V, 2.5 V, 3.3 V or 5 V Port P
  • Low standby current consumption of 1 μA
  • Schmitt-trigger action allows slow input transition and better switching noise immunity at the SCL and SDA inputs:
    • Vhys = 0.18 V (typical) at 1.8 V
    • Vhys = 0.25 V (typical) at 2.5 V
    • Vhys = 0.33 V (typical) at 3.3 V
    • Vhys = 0.5 V (typical) at 5 V
  • 5 V tolerant I/O ports
  • Active LOW reset input (RESET)
  • Open-drain active LOW interrupt output (INT)
  • 400 kHz Fast-mode I²C-bus
  • Internal power-on reset
  • Power-up with all channels configured as inputs
  • No glitch on power-up
  • Noise filter on SCL/SDA inputs
  • Latched outputs with 25 mA drive maximum capability for directly driving LEDs
  • Latch-up performance exceeds 100 mA per JESD 78, Class II
  • ESD protection exceeds JESD 22:
    • 2000 V Human-Body Model (A114-A)
    • 1000 V Charged-Device Model (C101)
  • Packages offered: HVQFN16, TSSOP16, XQFN16, XFBGA16 (1.6 mm x 1.6 mm x 0.5 mm), X2QFN16 (1.6 mm x 1.6 mm x 0.35 mm)

Agile I/O Features

  • Software backward compatible with PCA6408A with interrupts disabled at power-up
  • Pin-to-pin drop-in replacement for PCA6408A
  • Output port configuration: bank selectable push-pull or open-drain output stages
  • Interrupt status: read-only register identifies the source of an interrupt
  • Bit-wise I/O programming features:
    • Output drive strength: four programmable drive strengths to reduce rise and fall times in low-capacitance applications
    • Input latch: Input Port register values changes are kept until the Input Port register is read
    • Pull-up/pull-down enable: floating input or pull-up/pull-down resistor enable
    • Pull-up/pull-down selection: 100 kΩ pull-up/pull-down resistor selection
    • Interrupt mask: mask prevents the generation of the interrupt when input changes state to prevent spurious interrupts

Product Longevity Program

  • This product is included in the NXP Product Longevity Program ensuring a stable supply of products for your embedded designs. The PCAL6408APW is included in the 15-year program

Part numbers include: PCAL6408ABS, PCAL6408AEX1, PCAL6408AHK, PCAL6408APW.


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