4.11 Registers 44-4Dh: Voltage Limit Registers

Register

Address

Read/

Write

Register

Name

Bit 7

(MSB)

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

(LSB)

Default

Value

44h

R/W

2.5V Low Limit

7

6543210

00h

45h

R/W

2.5V High Limit

7

6543210

FFh

46h

R/W

V

7

6543210

00h

47h

R/W

V

7

6543210

FFh

48h

R/W

3.3V Low Limit

7

6543210

00h

49h

R/W

3.3V High Limit

7

6543210

FFh

4Ah

R/W

5V Low Limit

7

6543210

00h

4Bh

R/W

5V High Limit

7

6543210

FFh

4Ch

R/W

12V Low Limit

7

6543210

00h

4Dh

R/W

12V High Limit

7

6543210

FFh

If a voltage input either exceeds the value set in the voltage high limit register or falls below the value set in the voltage low limit

register, the corresponding bit will be set automatically by the LM85 in the interrupt status registers (41-42h). Voltages are

shown in Table 2.

Setting the Ready/Lock/Start/Override register Lock bit has no effect on these registers.

TABLE 2. Voltage Limits vs Register Setting

Input

Nominal

Voltage

Register Setting at

Nominal Voltage

Maximum

Voltage

Register Reading at

Maximum Voltage

Minimum

Voltage

Register Reading at

Minimum Voltage

2.5V

2.5V

C0h

3.32V

FFh

0V

00h

V

CCP

2.25V

C0h

3.00V

FFh

0V

00h

3.3V

3.3V

C0h

4.38V

FFh

3.0V

AFh

5V

5.0V

C0h

6.64V

FFh

0V

00h

12V

12.0V

C0h

16.00V

FFh

0V

00h

4.12 Registers 4E-53h: Temperature Limit Registers

Register

Address

Read/

Write

Register

Name

Bit 7

(MSB)

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

(LSB)

Default

Value

4Eh

R/W

Processor (Zone1)

Low Temp

7

6543210

81h

4Fh

R/W

Processor (Zone1)

High Temp

7

6543210

7Fh

50h

R/W

Processor (Zone2)

Low Temp

7

6543210

81h

51h

R/W

Processor (Zone2)

High Temp

7

6543210

7Fh

52h

R/W

Processor (Zone3)

Low Temp

7

6543210

81h

53h

R/W

Processor (Zone3)

High Temp

7

6543210

7Fh

If an external temperature input or the internal temperature sensor either exceeds the value set in the corresponding high limit

register or falls below the value set in the corresponding low limit register, the corresponding bit will be set automatically by the

LM85 in the Interrupt Status Register 1 (41h). For example, if the temperature read from the Remote1− and Remote1+ inputs

exceeds the Processor (Zone1) High Temp register limit setting, Interrupt Status Register 1 ZN1 bit will be set. The temperature

limits in these registers are represented as 8 bit, 2’s complement, signed numbers in Celsius, as shown below in Table 3.

Setting the Ready/Lock/Start/Override register Lock bit has no effect on these registers.

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