描述 Description

The PCA9561 is a 20-pin CMOS device consisting of four 6-bit non-volatile EEPROMregisters, six hardware pin inputs and a 6-bit multiplexed output. It is used for DIPswitch-free or jumper-less system configuration and supports Mobile and Desktop VIDConfiguration, where five preset values (four sets of internal non-volatile registers andone set of external hardware pins) set processor voltage for operation in variousperformance or battery conservation sleep modes. The PCA9561 is also useful in serverand telecommunications/networking applications when used to replace DIP switches orjumpers, since the settings can be easily changed via I2C-bus/SMBus without having topower down the equipment to open the cabinet. The non-volatile memory retains the mostcurrent setting selected before the power is turned off.
The PCA9561 typically resides between the CPU and Voltage Regulator Module (VRM)when used for CPU VID (Voltage IDentification code) configuration. It is used to bypassthe CPU-defined VID values and provide a different set of VID values to the VRM, if anincrease in the CPU voltage is desired. An increase in CPU voltage combined with anincrease in CPU frequency leads to a performance boost of up to 7.5 %. Lower CPUvoltage reduces power consumption. The main advantage of the PCA9561 over olderdevices, such as the PCA9559 or PCA9560, is that it contains four internal non-volatileEEPROM registers instead of just one or two, allowing five independent settings whichallows a more accurate CPU voltage tuning depending on specific applications.
The PCA9561 has two address pins, allowing up to four devices to be placed on the sameI2C-bus or SMBus.

特性 Features

Selection of non-volatile register_n as source to MUX_OUT pins via I2C-bus
I2C-bus can override MUX_SELECT pin in selecting output source
6-bit 5-to-1 multiplexer DIP switch
Four internal non-volatile registers
Internal non-volatile registers programmable and readable via I2C-bus
Six open-drain multiplexed outputs
400 kHz maximum clock frequency
Operating supply voltage 3.0 V to 3.6 V
5 V and 2.5 V tolerant inputs/outputs
Useful for Speed Step configuration of laptop computer
Two address pins, allowing up to four devices on the I2C-bus
MUX_IN values readable via I2C-bus
ESD protection exceeds 200 V HBM per JESD22-A114 and 1000 V CDM perJESD22-C101
Latch-up testing is done to JESDEC Standard JESD78 which exceeds 100 mA