ADT7483A

Rev. 1 | Page 12 of 24 | www.onsemi.com

Configuration 1 Register

Table 8. Configuration 1 Register (Read Address = 0x03, Write Address = 0x09)

Bit

Mnemonic

Function

7

Mask

Setting this bit to 1 masks all ALERTs on the ALERT pin. Default = 0 = ALERT enabled. This applies only if Pin 13

is configured as ALERT, otherwise it has no effect.

6

Mon/STBY

Setting this bit to 1 places the ADT7483A in standby mode, that is, suspends all temperature measurements

(ADC). The SMBus remains active and values can be written to, and read from, the registers. THERM and ALERT

are also active in standby mode. Changes made to the limit registers in standby mode that affect the THERM or

ALERT outputs will cause these signals to be updated. Default = 0 = temperature monitoring enabled.

5

AL/TH

This bit selects the function of Pin 13. Default = 0 = ALERT. Setting this bit to 1 configures Pin 13 as the

THERM2 pin.

4

Reserved

Reserved for future use.

3

Remote 1/Remote 2

Setting this bit to 1 enables the user to read the Remote 2 values from the Remote 1 registers.

Default = 0 = Remote 1 temperature values and limits are read from these registers. This bit is not lockable.

2

Temp Range

Setting this bit to 1 enables the extended temperature measurement range (−50°C to +150°C).

Default = 0 = 0°C to +127°C.

1

Mask R1

Setting this bit to 1 masks ALERTs due to the Remote 1 temperature exceeding a programmed limit.

Default = 0.

0

Mask R2

Setting this bit to 1 masks ALERTs due to the Remote 2 temperature exceeding a programmed limit.

Default = 0.

Configuration 2 Register

Table 9. Configuration 2 Register (Address = 0x24)

Bit

Mnemonic

Function

7

Lock Bit

Setting this bit to 1 locks all lockable registers to their current values. This prevents settings being

tampered with until the device is powered down. Default = 0.

<6:0>

Reserved

Reserved for future use.

Conversion Rate/Channel Selector Register

The conversion rate/channel selector register is at Address 0x04

for reads, and Address 0x0A for writes. The four LSBs of this

register are used to program the conversion times from 15.5 ms

(Code 0x0A) to 16 seconds (Code 0x00). To program the

ADT7483A to perform continuous measurements, set the

conversion rate register to 0x0B. For example, a conversion rate

of 8 conversions/second means that beginning at 125 ms

intervals, the device performs a conversion on the local and the

remote temperature channels.

This register can be written to and read back over the SMBus.

The default value of this register is 0x07, giving a rate of

8 conversions/second.

Bit 7 in this register can be used to disable averaging of the

temperature measurements. The ADT7483A can be configured

to take temperature measurements of either a single temperature

channel or all temperature channels. Bit 5 and Bit 4 can be used

to specify which temperature channel or channels are

measured.