Hot-selling and scarce PCA9545APWR Low Voltage 4-channel I2C and SMbus Switch 20TSSOP spot stock

Product Descriptions

The PCA9545A is a quad bidirectional  translatingswitch controlled via the I²C bus .  The SCL/SDAupstream pair fans out to four downstream pairs, orchannels .   Any  individual    SCn/SDn channel    orcombination of channels can be selected, determinedby the contents of the programmable control register .Four interrupt inputs (INT3–INT0), one for each of thedownstream pairs, are provided . One interrupt (INT)output acts as an AND of the four interrupt inputs .

An active-low reset   (RESET)   input   allows thePCA9545A to recover from a situation in which one ofthe downstream I²C buses is stuck in a low state .Pulling RESET low resets the I²C state machine andcauses all the channels to be deselected, as does theinternal power-on reset function .

The pass gates of the switches are constructed suchthat  the VCC terminal   can be used to limit  themaximum high voltage, which will  be passed by thePCA9545A .  This allows the use of  different  busvoltages on each pair, so that 1. 8-V, 2. 5-V, or 3. 3-Vparts can communicate with 5-V parts, without anyadditional   protection .  External   pull-up resistors pullthe bus up to the desired voltage level  for eachchannel . All I/O terminals are 5.5 V tolerant .

Product Features

•   1-of-4 Bidirectional Translating Switches

•   I2C Bus and SMBus Compatible

•   Four Active-Low Interrupt Inputs

•   Active-Low Interrupt Output

•   Active-Low Reset Input

•   Two Address Terminals, Allowing up to Four Devices on the I2C Bus

•   Channel Selection via I2C Bus, in Any Combination

•   Power-Up With All Switch Channels Deselected

•   Low RON Switches

•   Allows Voltage-Level Translation Between 1. 8-V, 2. 5-V, 3. 3-V, and 5-V Buses

•   No Glitch on Power-Up

•   Supports Hot Insertion

•   Low Standby Current

•   Operating Power-Supply Voltage Range of 2.3 V to 5.5 V

•   5.5 V Tolerant Inputs

•   0 to 400-kHz Clock Frequency

•   Latch-Up Performance Exceeds 100 mA per JESD 78

•   ESD Protection Exceeds JESD 22

– 2000-V Human-Body Model (A114-A)

– 1000-V Charged-Device Model (C101)

Product Applications

•   Servers

•   Routers (Telecom Switching Equipment)

•   Factory Automation

•   Products With I2C Slave Address Conflicts (e . g .Multiple, Identical Temp Sensors)

Product Specifications

Product Photos

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