MAX6661AEE Maxim Integrated Products, MAX6661AEE Datasheet
MAX6661AEE
Specifications of MAX6661AEE
Related parts for MAX6661AEE
MAX6661AEE Summary of contents
Page 1
... Fan Speed o Accurate Closed-Loop Fan-Speed Regulation o On-Chip Power Device Drives Fans Rated Up to 250mA o Programmable Under/Overtemperature Alarms o SPI-Compatible Serial Interface o ±1°C (+60°C to +100°C) Thermal-Sensing Accuracy PART MAX6661AEE Applications 1µF PENTIUM Features Ordering Information TEMP RANGE PIN-PACKAGE -40°C to +125°C ...
Page 2
Remote Temperature-Controlled Fan-Speed Regulator with SPI-Compatible Interface ABSOLUTE MAXIMUM RATINGS , ALERT, OVERT ...............................................-0. TACH IN, FAN .............................................-0.3V to +16V FAN DXP, CS, SDOUT, GAIN, SCL, SDIN..........-0. DXN ..........................................................................-0.3V to +1V SDOUT ...
Page 3
Remote Temperature-Controlled Fan-Speed Regulator with SPI-Compatible Interface ELECTRICAL CHARACTERISTICS (continued 5.5V 12V -40°C to +125°C, unless otherwise specified. Typical values are FAN A +25°C.) (Notes 1 and 2) PARAMETER ...
Page 4
Remote Temperature-Controlled Fan-Speed Regulator with SPI-Compatible Interface (T = +25°C, unless otherwise noted.) A TEMPERATURE ERROR vs. PC BOARD RESISTANCE PATH = DXP TO GND -10 PATH = DXP TO V (5V) CC -15 ...
Page 5
Remote Temperature-Controlled Fan-Speed Regulator with SPI-Compatible Interface PIN NAME 1 V Power Supply for Fan Drive: 4.5V to 13.5V FAN 2 V Power Supply 5.5V. Bypass with a 0.1µF capacitor to GND DXP Input: Remote-Junction Anode. ...
Page 6
Remote Temperature-Controlled Fan-Speed Regulator with SPI-Compatible Interface DXP MUX ADC DXN CONTROL LOGIC SC SDIN SPI INTERFACE DOUT CS Figure 1. MAX6661 Block Diagram 6 _______________________________________________________________________________________ FAN-SPEED REGULATOR REGISTERS T MAX T COMPARAT0R HYST REMOTE TEMPERATURE DATA T HIGH T ...
Page 7
Remote Temperature-Controlled Fan-Speed Regulator with SPI-Compatible Interface Table 1. Remote-Sensor Transistors MANUFACTURER Central Semiconductor (USA) Fairchild Semiconductor (USA) Rohm Semiconductor (Japan) Samsung (Korea) Siemens (Germany) Zetex (England) Note: Transistors must be diode connected (base shorted to collector). The transistor must ...
Page 8
Remote Temperature-Controlled Fan-Speed Regulator with SPI-Compatible Interface 5) When introducing a thermocouple by inserting differ- ent metals in the connection path, make sure that both the DXP and the DXN paths have matching thermocouples, i.e., the connection paths are sym- ...
Page 9
Remote Temperature-Controlled Fan-Speed Regulator with SPI-Compatible Interface Table 2. MAX6661 Command-Byte Bit Assignments REGISTERS COMMAND RRL 81h RRH 83h RSL 85h RCL/WCL 87h/92h RFCR/WFCR 89h/94h RTMAX/WTMAX A1h/A4h RTHYST/WTHYST A3h/A6h RTHIGH/WTHIGH 8Fh/9Ah RTLOW/WTLOW 91h/9Ch SPOR F8h OSHT 9Eh RTFAN/WTFAN A9h/B2h RFSC/WFSC ...
Page 10
Remote Temperature-Controlled Fan-Speed Regulator with SPI-Compatible Interface SC CS D15 DIN D15 IS START BIT COMMAND BYTE ALWAYS HIGH THREE-STATE DOUT Figure 3. Read Cycle SC CS D15 DIN D15 IS START BIT D15–D8 COMMAND BYTE ALWAYS HIGH THREE-STATE DOUT ...
Page 11
Remote Temperature-Controlled Fan-Speed Regulator with SPI-Compatible Interface +127°C, for T is -55°C, for T LOW MAX T is +95°C. HYST Overtemperature Output ( OVERT ) The MAX6661 has an overtemperature output (OVERT) that is set when the remote-diode temperature crosses ...
Page 12
Remote Temperature-Controlled Fan-Speed Regulator with SPI-Compatible Interface Table 4. Configuration Register Bit Assignments BIT NAME POR STATE ALERT Mask 7(MSB) 6 Run/Stop OVERT Polarity 5 4 Write Protect Thermal Closed/ 3 Open Loop OVERT Input Inhibit 2 Mask OVERT 1 ...
Page 13
Remote Temperature-Controlled Fan-Speed Regulator with SPI-Compatible Interface on the amount of time between status read operations. In these circumstances best not to rely on the sta- tus bits to indicate reversals in long-term temperature changes. Instead, use a ...
Page 14
Remote Temperature-Controlled Fan-Speed Regulator with SPI-Compatible Interface REMOTE SENSOR TEMPERATURE CONVERTER TEMP DATA UPDATE FCR 0.25s TO 16s UPDATE FAN THRESHOLD TEMPERATURE (T ) FAN FAN-SPEED TACH IN CONTROL (FSC) Figure 6. MAX6661 Thermal Loop In thermal open-loop mode, the ...
Page 15
Remote Temperature-Controlled Fan-Speed Regulator with SPI-Compatible Interface Table 7. Fan Speed Control Register (RFSC/WFSC) REGISTER/ADDRESS COMMAND 7 Label Not Used POR State 0 Table 8. Fan Gain Register (RFG/WFG) REGISTER/ADDRESS COMMAND 7 Always Label Write a 1 POR State 1 ...
Page 16
Remote Temperature-Controlled Fan-Speed Regulator with SPI-Compatible Interface using the FSC register. By selecting fan open-loop mode, the MAX6661 automatically invokes thermal open-loop mode. Fan Conversion Rate Register The FCR register (Table 6) programs the fan’s update time interval in free-running ...
Page 17
Remote Temperature-Controlled Fan-Speed Regulator with SPI-Compatible Interface REF FREQ 8415Hz FAN TACHOMETER TACH IN Figure 7. MAX6661 Fan Loop Functional Diagram Table 11. Fan Tachometer Period Limit (RFTCL/WWFTCL) REGISTER/ADDRESS COMMAND 7 Label (MSB) POR State 1 Note: The fan tachometer ...
Page 18
Remote Temperature-Controlled Fan-Speed Regulator with SPI-Compatible Interface The 83.4Hz value is out of the 33Hz to 66Hz decre- ment/increment range. Set bits in the FTD register to divide the signal down within the 33Hz to 66Hz range. Bits 1, 0 ...
Page 19
... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 19 © 2002 Maxim Integrated Products ...