STV0684 datasheet(22/49 Pages) STMICROELECTRONICS

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Functional Description

STV0684

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3.10

Other interfaces

3.10.1 SPI

The SPI interface is a generic serial interface that can be used to perform the following functions:

● Support for Multi-media and Secure Digital Cards

● Support for serial flash where code can be located

The SPI supports:

● Full duplex, three-wire synchronous transfers

● Single, master/slave operation selectable either through firmware or hardware

● Programmable clock polarity and phase

● End of transfer interrupt flag

● Write collision flag

● Busy flag indication

3.10.2 I2C

The STV0684 features a hardware I2C master interface and supports the following features:

● I2C protocol

● Standard I2C mode (100 Khz)/Fast I2C mode (400 Khz)

● Single master mode

● Transmitter/Receiver performance

● 7/10 bit addressing

● DMA mode data transfer

● Clock stretching

3.10.3 Comparator for low battery detection

The comparator circuit was designed to compare the battery voltage (after an external resistor

divider) with an external reference voltage and generate a low_batt (high when battery voltage is

lower than the present threshold) signal for the CPU core.

STV0684 Datasheet(PDF) 22 Page - STMicroelectronics