1 Features

• I²C to Parallel-Port Expander
• Open-Drain Interrupt Output
• Low Standby-Current Consumption of 10 μA Maximum
• Compatible With Most Microcontrollers
• 400-kHz Fast I²C Bus
• Address by Three Hardware Address Pins for Use of up to Eight Devices
• Latched Outputs With High-Current Drive 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
  • 200-V Machine Model
  • 1000-V Charged-Device Model

2 Applications

• Telecom Shelters: Filter Units
• Servers
• Routers (Telecom Switching Equipment)
• Personal Computers
• Personal Electronics
• Industrial Automation
• Products with GPIO-Limited Processors

3 Description

This 16-bit I/O expander for the two-line bidirectional bus (I²C) is designed for 4.5-V to 5.5-V V_CC operation.

The PCF8575C provides general-purpose remote I/O expansion for most microcontroller families via the I²C interface serial clock (SCL) and serial data (SDA).

The device features a 16-bit quasi-bidirectional input/output (I/O) port (P07–P00, P17–P10), including latched outputs with high-current drive capability for directly driving LEDs. Each quasi-bidirectional I/O can be used as an input or output without the use of a data-direction control signal. At power on, the I/Os are in 3-state mode. The strong pullup to V_CC allows fast-rising edges into heavily loaded outputs. This device turns on when an output is written high and is switched off by the negative edge of SCL. The I/Os should be high before being used as inputs. After power on, as all the I/Os are set to 3-state, all of them can be used as inputs. Any change in setting of the I/Os as either inputs or outputs can be done with the write mode. If a high is applied externally to an I/O that has been written earlier to low, a large current (I_OL) flows to GND.

1. For all available packages, see the orderable addendum at the end of the data sheet.