深圳市谷科智电子有限公司

描述

The PCA9544A is a quad bidirectional translating switch controlled via the I2C bus. The SCL/SDA upstream pair fans out to four downstream pairs, or channels. One SCL/SDA pair can be selected at a time, and this is determined by the contents of the programmable control register. Four interrupt inputs (INT3–INT0), one for each of the downstream pairs, are provided. One interrupt output (INT) acts as an AND of the four interrupt inputs.

A power-on reset function puts the registers in their default state and initializes the I2C state machine, with no channel selected.

The pass gates of the switches are constructed such that the VCC pin can be used to limit the maximum high voltage, which will be passed by the PCA9544A. This allows the use of different bus voltages on each pair, so that 1.8-V, 2.5-V, or 3.3-V parts can communicate with 5-V parts, without any additional protection. External pull-up resistors pull the bus up to the desired voltage level for each channel. All I/O pins are 5-V tolerant.For all available packages, see the orderable addendum at the end of the data sheet.特性1-of-4 Bidirectional Translating SwitchesI2C Bus and SMBus CompatibleFour Active-Low Interrupt InputsActive-Low Interrupt OutputThree Address Pins, Allowing up to Eight Devices on the I2C BusChannel Selection Via I2C BusPower Up With All Switch Channels DeselectedLow RON SwitchesAllows Voltage-Level Translation Between 1.8-V, 2.5-V, 3.3-V, and 5-V BusesNo Glitch on Power UpSupports Hot InsertionLow Standby CurrentOperating Power-Supply Voltage Range of 2.3 V to 5.5 V5.5-V Tolerant Inputs0 to 400-kHz Clock FrequencyLatch-Up Performance Exceeds 100 mA Per JESD 78ESD Protection Exceeds JESD 222000-V Human-Body Model (A114-A)200-V Machine Model (A115-A)1000-V Charged-Device Model (C101