NCT1008DMN3R2G datasheet(10/20 Pages) ONSEMI

Part #	NCT1008DMN3R2G

Description	짹1?C Temperature Monitor with Series Resistance Cancellation

Download	20 Pages

Scroll/Zoom	100%

Manufacturer	ONSEMI [ON Semiconductor]

Direct Link	http://www.onsemi.com

Logo

10 / 20 page

NCT1008

http://onsemi.com

10

Conversion Rate Register

The conversion rate register is Address 0x04 at read and

Address 0x0A at write. The lowest four bits of this register

are used to program the conversion rate by dividing the

internal oscillator clock by 1, 2, 4, 8, 16, 32, 64, 128, 256,

512, or 1024 to give conversion times from 15.5 ms (Code

0x0A) to 16 seconds (Code 0x00). For example, a

conversion rate of eight conversions per second means that

beginning at 125 ms intervals, the device performs a

conversion on the internal and the external temperature

channels.

The conversion rate register can be written to and read

back over the SMBus/I2C. The higher four bits of this

register are unused and must be set to 0. The default value

of this register is 0x08, giving a rate of 16 conversions per

second. Use of slower conversion times greatly reduces the

device power consumption.

Table 4. Conversion Rate Register Codes

Code

Conversion/Second

Time (Seconds)

0x00

0.0625

16

0x01

0.125

8

0x02

0.25

4

0x03

0.5

2

0x04

1

0x05

2

500 m

0x06

4

250 m

0x07

8

125 m

0x08

16

62.5 m

0x09

32

31.25 m

0x0A

64

15.5 m

0x0B to 0xFF

Reserved

Limit Registers

The NCT1008 has eight limit registers: high, low, and

THERM temperature limits for both local and remote

temperature measurements. The remote temperature high

and low limits span two registers each, to contain an upper

and lower byte for each limit. There is also a THERM

hysteresis register. All limit registers can be written to, and

read back over, the SMBus. See Table 8 for details of the

limit register addresses and their power−on default values.

When Pin 6 is configured as an ALERT output, the high

limit registers perform a > comparison, while the low limit

registers perform a

≤ comparison. For example, if the high

limit register is programmed with 80

°C, then measuring

81

°C results in an out−of−limit condition, setting a flag in

the status register. If the low limit register is programmed

with 0

°C, measuring 0°C or lower results in an out−of−limit

condition.

Exceeding either the local or remote THERM limit asserts

THERM low. When Pin 6 is configured as THERM2,

exceeding either the local or remote high limit asserts

THERM2 low. A default hysteresis value of 10

°C is

provided that applies to both THERM channels. This

hysteresis value can be reprogrammed to any value after

powerup (Register Address 0x21).

It is important to remember that the temperature limits

data format is the same as the temperature measurement data

format. Therefore, if the temperature measurement uses

default binary, then the temperature limits also use the

binary scale. If the temperature measurement scale is

switched, however, the temperature limits do not

automatically switch. The user must reprogram the limit

registers to the desired value in the correct data format. For

example, if the remote low limit is set at 10

°C with the

default binary scale, the limit register value is 0000 1010b.

If the scale is switched to offset binary, the value in the low

temperature limit register needs to be reprogrammed to

0100 1010b.

Status Register

The status register is a read−only register at Address 0x02.

It contains status information for the NCT1008.

When Bit 7 of the status register is high, it indicates that the

ADC is busy converting. The other bits in this register flag the

out−of−limit temperature measurements (Bit 6 to Bit 3, and

Bit 1 to Bit 0) and the remote sensor open circuit (Bit 2).

If Pin 6 is configured as an ALERT output, the following

applies: If the local temperature measurement exceeds its

limits, Bit 6 (high limit) or Bit 5 (low limit) of the status

register asserts to flag this condition. If the remote

temperature measurement exceeds its limits, then Bit 4 (high

limit) or Bit 3 (low limit) asserts. Bit 2 asserts to flag an open

circuit condition on the remote sensor. These five flags are

NOR’ed together, so if any of them is high, the ALERT

interrupt latch is set and the ALERT output goes low.

Reading the status register clears the five flags, Bit 6 to

Bit 2, provided the error conditions causing the flags to be

set have gone away. A flag bit can be reset only if the

corresponding value register contains an in−limit

measurement or if the sensor is good.

The ALERT interrupt latch is not reset by reading the

status register. It resets when the ALERT output has been

serviced by the master reading the device address, provided

the error condition has gone away and the status register flag

bits are reset.

When Flag 1 and/or Flag 0 are set, the THERM output

goes low to indicate that the temperature measurements are

outside the programmed limits. The THERM output does

not need to be reset, unlike the ALERT output. Once the

measurements are within the limits, the corresponding status

register bits are automatically reset and the THERM output

goes high. The user may add hysteresis by programming

Register 0x21. The THERM output is reset only when the

temperature falls to limit value minus the hysteresis value.

When Pin 6 is configured as THERM2, only the high

temperature limits are relevant. If Flag 6 and/or Flag 4 are

set, the THERM2 output goes low to indicate that the

temperature measurements are outside the programmed

limits. Flag 5 and Flag 3 have no effect on THERM2. The

behavior of THERM2 is otherwise the same as THERM.

Similar Part No. - NCT1008DMN3R2G

Manufacturer	Part #	Datasheet	Description
ON Semiconductor	NCT1008DMN3R2G	333Kb / 20P	Temperature Monitor July, 2012 ??Rev. 6

More results

Similar Description - NCT1008DMN3R2G

Manufacturer	Part #	Datasheet	Description
ON Semiconductor	ADT7461A	282Kb / 19P	짹1??Temperature Monitor with Series Resistance Cancellation December, 2009 ??Rev. 6
	ADT7461	291Kb / 20P	짹1??Temperature Monitor with Series Resistance Cancellation December, 2009 ??Rev. 6
	NCT72	328Kb / 21P	1C Temperature Monitor with Series Resistance Cancellation August, 2012 ??Rev. 4
	NVT211	287Kb / 19P	1C Temperature Monitor with Series Resistance Cancellation December, 2013 ??Rev. 0
	NVT210	331Kb / 20P	1C Temperature Monitor with Series Resistance Cancellation May, 2013 ??Rev. 7
	NCT214	253Kb / 20P	1C Temperature Monitor with Series Resistance Cancellation April, 2014 ??Rev. 4
	NCT72CMTR2G	331Kb / 20P	Temperature Monitor with Series Resistance Cancellation August, 2012 ??Rev. 4
	NCT72	255Kb / 20P	Temperature Monitor with Series Resistance Cancellation June, 2017 ??Rev. 5
	NCT214MT3R2G	322Kb / 19P	Temperature Monitor with Series Resistance Cancellation July, 2012 ??Rev. 1
	ADT7461	274Kb / 20P	Temperature Monitor with Series Resistance Cancellation March, 2014 ??Rev. 8

More results

NCT1008DMN3R2G Datasheet(PDF) 10 Page - ON Semiconductor

NCT1008DMN3R2G Datasheet(HTML) 10 Page - ON Semiconductor

Similar Part No. - NCT1008DMN3R2G

Similar Description - NCT1008DMN3R2G

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

Datasheet Download

Link URL