Electronic Components Datasheet Search |
|
IS31FL3731-QFLS2-TR Datasheet(PDF) 7 Page - Integrated Silicon Solution, Inc |
|
IS31FL3731-QFLS2-TR Datasheet(HTML) 7 Page - Integrated Silicon Solution, Inc |
7 / 22 page IS31FL3731 Integrated Silicon Solution, Inc. – www.issi.com 7 Rev.D, 04/22/2013 DETAILED DESCRIPTION I2C INTERFACE The IS31FL3731 uses a serial bus, which conforms to the I2C protocol, to control the chip’s functions with two wires: SCL and SDA. The IS31FL3731 has a 7-bit slave address (A7:A1), followed by the R/W bit, A0. Set A0 to “0” for a write command and set A0 to “1” for a read command. The value of bits A1 and A2 are decided by the connection of the AD pin. The complete slave address is: Table 1 Slave Address (Write only): Bit A7:A3 A2:A1 A0 Value 11101 AD 0/1 AD connected to GND, AD=00; AD connected to VCC, AD=11; AD connected to SCL, AD=01; AD connected to SDA, AD=10; The SCL line is uni-directional. The SDA line is bi- directional (open-collector) with a pull-up resistor (typically 4.7kΩ). The maximum clock frequency specified by the I2C standard is 400kHz. In this discussion, the master is the microcontroller and the slave is the IS31FL3731. The timing diagram for the I2C is shown in Figure 3. The SDA is latched in on the stable high level of the SCL. When there is no interface activity, the SDA line should be held high. The “START” signal is generated by lowering the SDA signal while the SCL signal is high. The start signal will alert all devices attached to the I2C bus to check the incoming address against their own chip address. The 8-bit chip address is sent next, most significant bit first. Each address bit must be stable while the SCL level is high. After the last bit of the chip address is sent, the master checks for the IS31FL3731’s acknowledge. The master releases the SDA line high (through a pull-up resistor). Then the master sends an SCL pulse. If the IS31FL3731 has received the address correctly, then it holds the SDA line low during the SCL pulse. If the SDA line is not low, then the master should send a “STOP” signal (discussed later) and abort the transfer. Following acknowledge of IS31FL3731, the register address byte is sent, most significant bit first. IS31FL3731 must generate another acknowledge indicating that the register address has been received. Then 8-bit of data byte are sent next, most significant bit first. Each data bit should be valid while the SCL level is stable high. After the data byte is sent, the IS31FL3731 must generate another acknowledge to indicate that the data was received. The “STOP” signal ends the transfer. To signal “STOP”, the SDA signal goes high while the SCL signal is high. ADDRESS AUTO INCREMENT To write multiple bytes of data into IS31FL3731, load the address of the data register that the first data byte is intended for. During the IS31FL3731 acknowledge of receiving the data byte, the internal address pointer will increment by one. The next data byte sent to IS31FL3731 will be placed in the new address, and so on. The auto increment of the address will continue as long as data continues to be written to IS31FL3731 (Figure 6). READING PORT REGISTERS All of registers in IS31FL3731 can be read. But Frame Registers can only be read in software shutdown mode as SDB pin is high. The Function Register can be read in software shutdown mode or operating mode. To read the device data, the bus master must first send the IS31FL3731 address with the R/W ____ bit set to “0”, followed by the Command Register address, FDh, then send command data which determines which response register is accessed. After a restart, the bus master must send the IS31FL3731 address with the R/W ____ bit set to “0” again, followed by the register address which determines which register is accessed. Then restart I2C, the bus master should send the IS31FL3731 address with the R/W ____ bit set to “1”. Data from the register defined by the command byte is then sent from the IS31FL3731 to the master (Figure 7). Figure 3 Interface timing |
Similar Part No. - IS31FL3731-QFLS2-TR |
|
Similar Description - IS31FL3731-QFLS2-TR |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.NET |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |