 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
MAX6620ATI+ Datasheet(PDF) 8 Page - Maxim Integrated Products |
|
||||||||||||||||||||||||||||||
MAX6620ATI+ Datasheet(HTML) 8 Page - Maxim Integrated Products |
|
|
8 / 30 page  MAX6620 Quad Linear Fan-Speed Controller 8 Maxim Integrated Write Byte Format Read Byte Format Send Byte Format Receive Byte Format Slave Address: equiva- lent to chip-select line of a 3-wire interface Command Byte: selects which register you are writing to Data Byte: data goes into the register set by the command byte (to set thresholds, configuration masks, and sampling rate) Slave Address: equiva- lent to chip-select line Command Byte: selects which register you are reading from Slave Address: repeated due to change in data- flow direction Data Byte: reads from the register set by the command byte Command Byte: sends com- mand with no data, usually used for one-shot command Data Byte: reads data from the register commanded by the last read byte or write byte transmission; also used for SMBus alert response return address S = START CONDITION SHADED = SLAVE TRANSMISSION P = STOP CONDITION A = NOT ACKNOWLEDGED Figure 2. I2C Protocols S ADDRESS RD A DATA A P 7 bits 8 bits WR S A COMMAND A P 8 bits ADDRESS 7 bits P 1 A DATA 8 bits A COMMAND 8 bits A WR ADDRESS 7 bits S S ADDRESS WR A COMMAND A S ADDRESS 7 bits 8 bits 7 bits RD A DATA 8 bits A P Detailed Description The MAX6620 controls the speeds of up to four fans using four independent linear voltage outputs. The drive voltages for the fans are controlled directly over the I2C interface. Each of the outputs (DACOUT1– DACOUT4) drive the base of an external PNP or the gate of a p-channel MOSFET. Voltage feedback at the fan’s power-supply terminal is used to force the output voltage. The MAX6620 monitors fan tachometer logic outputs for precise (1%) control of fan RPM and detection of fan failure. When the MAX6620 is used with 2-wire fans, these inputs are not used, and the fans can be driven to the desired voltage without using tachometer feed- back. Three inputs set the fan drive status on application of power. The DAC_START input selects the fan-supply voltage (100%, 75%, or 0%) at startup to ensure appro- priate fan drive when power is first applied. The SPIN_START input selects whether spin-up will be applied to the fans at power-up. WD_START selects whether lack of I2C activity will force the fans to full speed. When the watchdog function is enabled, the fans will be driven to full speed if there is no I2C activity for a period of 2s, 6s, or 10s. Digital Interface The MAX6620 features an I2C-compatible, 2-wire serial interface consisting of a bidirectional serial data line (SDA) and a serial clock line (SCL). SDA and SCL facili- tate bidirectional communication between the MAX6620 and the master at rates up to 400kHz. The master (typi- cally a microcontroller) initiates data transfer on the bus and generates SCL. SDA and SCL require 4.7k Ω (typ) pullup resistors. Bit Transfer One data bit is transferred during each SCL clock cycle. Nine clock cycles are required to transfer the data into or out of the MAX6620. The data on SDA must remain stable during the high period of the SCL clock pulse, as changes in SDA while SCL is high are control signals (see the START and STOP Conditions section). Both SDA and SCL idle high. |
Similar Part No. - MAX6620ATI+ |
|
Similar Description - MAX6620ATI+ |
|
|
Link URL |
| Privacy Policy |
| ALLDATASHEET.COM |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | 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 |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
