NCT6104D

NCT6106D/ NCT6104D/ NCT6102D Application Note 2.8 Feature Brief NCT6106D/ NCT6104D/ NCT6102D: LPC I/F + UART + Parallel Port + KBC + ACPI + Hardware Monitor + GPIOs + PECI + DSW logic + AMDTSI + ERP Subject This application note is applicable to all version chips except for the explicitly specified ones. Description 1. Layout for Temperature Detection Pin Since the NCT6106D/NCT6104D/NCT6102D supports remote diode temperature sensing through Current Mode, the layout is one of the important factors. The following items should be handled with care. Please pay attention to the following steps. 1) Place the NCT6106D/NCT6104D/NCT6102D closely to the thermal diode of the processor. The traces of D+ and D- should be as short and parallel as possible. 2) Put the recommended 2200pF capacitor between NCT6106D/NCT6104D/NCT6102D’s CPUTIN (pin103) and AGND (pin105) as close as possible. 3) Pin105 of the NCT6106D/NCT6104D/NCT6102D is also an analog GND for ADC of H/W Monitor block; therefore, please separate it from normal power GND. The circuit is shown in the following figure. SIO W83627UHG Thermal Diode D+ C= 2200pF D- CPUTIN (SYSTIN) AGND AGND 2. Battery power consumption To save the battery power at pin74, please connect CASEOPEN# (pin76) to VBAT (pin74) with a 2M ohm pulled-up resistor if CASEOPEN function is not in use. Page 1 of 8 11/10/2014 3. EOS damages resulted from pin72 (PSON#) To avoid EOS damages to pin72 (PSON#), following protection circuit is recommended. Add R (serial resister) and D1 (EOS protection diode) to avoid this issue on pin72 (PSON#). 4. Deal with unused input pins Keep a fixed level on unused input pins to minimize the power consumption. 5. Unused PECI pin SIO PECI pin could be floated if it is unused. 6. A 4.7uF bypass capacitor is added with VREF (pin102) Since all of the monitored inputs are converted to digital values by a built-in, eight-bit analog-todigital converter (ADC) of the NCT6106D/NCT6104D/NCT6102D and the VREF value is used as a reference voltage for this ADC. For better accuracy of the monitored inputs, adding a 4.7uF capacitor to AGND (pin 105) is needed. 7. 14.7456MHZ_CLKIN (pin108) SIO UART have four source clocks can be selected. In UART clock 14.769 MHz, SIO NCT6106D/NCT6104D/NCT6102D has two clock sources, one is internal clock (24MHz / 1.625), another one is external clock from pin108 14.7456MHZ_CLKIN. In order to get better UART frequency accuracy, it’s recommended to use external clock input (14.7456MHZ_CLKIN pin108). Please note pin108 default function is GP67, BIOS can switch this pin to 14.7456MHZ_CLKIN function later. Page 2 of 8 11/10/2014 8. Watch Dog Timer Application Please be noted that the Watch Dog Timer function is enabled by default in NCT6106D/NCT6104D/NCT6102D. This is located at Logical Device 8, CR [30h], bit [0]. The unit of Watch Dog Timer counter can be selected at Logical Device 8, CR [F0h], bit [3]. The time-out value is set at Logical Device 8, CR [F1h], and the default is 4 sec. Writing a zero to this register disables the Watch Dog Timer function. Writing any non-zero value to this register causes the counter to load this value into the Watch Dog Timer counter and start counting down. It is reset by either LRESET# signal (default) or PWROK signal. 9. DC Fan Output Application Please be noted that the maximum voltage of DC output mode of all fan control pins (SYSFANOUT, CPUFANOUT, and AUXFANOUT) is 2.048V in NCT6106D / NCT6104D / NCT6102D. 10. Intel DSW function Application To use NCT6106D/NCT6104D/NCT6102D DSW pins, the following hardware and software application note should be followed. Table 1 defines and explains the power well name for Intel DSW application. It also describes their existence (V or X) of each system states. POWER SOURCE DESCRIPTION V5A 5V always power from ATX Power Supply V5A will output a 3.3V always power via LDO or PWM Power IC. The power will be provide to NCT610XD VSB power pin and PCH VCCDSW3_3 power pin. 5V Suspend power, it will be cut in DSW state. 3.3V Suspend Power, it will be cut in DSW state. The Power will provide to PCH VCCSUS3_3 power pin. NCT610XD PCHVSB pin will detect the 3VSB power via 1kohm resistor. 5V Dual power, like USB power source. V3A 5VSB 3VSB 5VDUAL DSW (DEEP S5/S4) V S5/S4 S3 V V V V V X V V X V V X Option V Table 1. Page 3 of 8 11/10/2014 Table 2 shows NCT6106D/NCT6104D/NCT6102D DSW pins’ name and characteristics, and recommended pull-up power well. 81 83 85 67 75 NCT610XD PIN NAME SLP_SUS# SUSACK# SUSWARN# PSOUT# RSMRST# 84 5VDUAL SYSTEM 5VDUAL 69 PCHVSB SYSTEM 3VSB PIN 80 SLP_SUS_FET 82 SUSWARN_5VDUAL CONNECT TO INTEL PCH SLP_SUS# SUSACK# SUSWARN# PWRBTN# RSMRST# POWER DETECT POWER CONTROL PULL-UP POWER SOURCE 3VSB V3A 3VSB 5VDUAL power must be scaled down to 3V for detection. Note 1 3VSB (1Kohm) Control 5VSB/3VSB power switch 0: Turn ON VSB 1: Turn OFF VSB Control 5VDUAL power switch 0: Turn ON 5VDUAL 1: Turn OFF 5VDUAL 5VSB 5VSB Note 1. 5VDUAL power should be scaled to 3V by divided resistors as the following diagram. 5VDUAL_sense is connected to NCT6106D / NCT6104D / NCT6102D 5VDUAL pin (pin84). 5VDUAL R214 30k 5VDUAL sense R215 51k Logical Device 16 CR30h bit3 and bit 6 must be set to 1 by BIOS. Page 4 of 8 11/10/2014 11. KBRST# and GA20M function Application KBRST# and GA20M pins will be high level after 3VSB supplied by NCT6106D/NCT6104D /NCT6102D push-pull output logic. Please implement an isolation with 3VCC to avoid the leakage before system on. 12. Watch Dog Timer Accuracy When the Watch Dog Timer setting is less than 15 sec, it is suggested that BIOS compensate 1~2 sec for more accuracy. For example, if the target Watch Dog Timer is 10 sec, BIOS needs to set it as 8 sec to compensate for the accuracy. 13. UART RS485 Auto Flow Control [For rev. B] NCT6102D / NCT6104D / NCT6106D supports RS485 auto flow control function for all UART. When enabling the RS485 auto control function, it will automatically drive RTS# pin to logic high or low for flow control. To make this RS485 auto flow control function work, please be noted that the parity and stop-bit setting has to be one of the following three settings: (1) 8 data bits + 1 parity bit + 1 stop bit (2) 8 data bits + 1 parity bit + 2 stop bits (3) 8 data bits + 2 stop bits [For rev. C] To make this RS485 auto flow control function work, please set either 8 data bits + 1 stop bit Or one of the following three settings: Page 5 of 8 11/10/2014 (1) 8 data bits + 1 parity bit + 1 stop bit (2) 8 data bits + 1 parity bit + 2 stop bits (3) 8 data bits + 2 stop bits 14. Status of UARTs output pins while UARTs are inactive UART output pins are SOUT, RTS#, and DTR#. When UART ports are inactive, the status of the UART output pins are tri-state by default. To keep the status of the UART output pins logic high, please reserve the pull-up resisters for the UART output pins. For those UART output pins that are related to strapping functions, it needs BIOS to change the strapping value to high by CR 26h and CR 2Fh in Chip (Global) Control Register if these pins are strapped low. However, for pin #51 or RTSA# (2E_4E_SEL), if it is strapped low for SIO address selection, then please keep UART A active so that the RTSA# output will be high. Pin Number 51 52 54 111 112 Pin Names RTSA# DTRA# SOUTA RTSC# DTRC# Strapping Function 2E_4E_SEL 24M_48M_SEL GPIO_PORT80_SEL SOUTC_P80_SEL SOUTE_P80_SEL Page 6 of 8 11/10/2014 NCT6106D / NCT6104D / NCT6102D Application Note DATE DOCUMENT REVISION REMARK 11/09/2011 APN 1.0 First release. 05/28/2012 APN 2.0 Add Watch Dog Timer application and fan DC mode application 10/05/2012 APN 2.1 Add DSW function application 10/26/2012 APN 2.2 Added KBRST# function application. 03/28/2013 APN 2.3 Add Watch Dog Timer accuracy 05/10/2013 APN 2.4 Update item 9, item 11 and add item 13 05/20/2013 APN 2.5 Remove unnecessary note in item 9 -- DC Fan Output Application 09/10/2013 APN 2.6 Add NCT6104D and NCT6102D in the APN Page 7 of 8 11/10/2014 DATE DOCUMENT REVISION REMARK 10/17/2014 APN 2.7 Status of UARTs output pins while UARTs are inactive 11/10/2014 APN 2.8 Update item #13, UART Auto Flow Control application for both rev. B and rev. C Page 8 of 8 11/10/2014