Functional Description (Continued)
13.3 Test Register—Address 15h
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Power on default – 7:0 = 00000000 binary
Bit
0
Name
Shutdown
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Read/Write
Description
Read/Write A one places the LM87 in a lower power "Shutdown" mode.
1
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
2
3
4
5
6
7
13.4 Channel Mode Register—Address 16h
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>
Power on default – 7:0 = 00000000 binary
Bit
0
Name
Read/Write
Description
FAN1/AIN1
Read/Write A one enables the input as AIN1, a zero enables the input as FAN1.
Read/Write A one enables the input as AIN2, a zero enables the input as FAN2.
Read/Write A one enables the 2.5V, VCCP2/D2 inputs as a second remote diode temperature input.
Read/Write A one configures the LM87 for 5.0V VCC measurement. A zero configures it for 3.3V
VCC measurement.
1
FAN2/AIN2
2
2.5V, VCCP2/D2
Int. VCC Range
3
4
5
6
7
IRQ0 EN
IRQ1 EN
IRQ2 EN
VID/IRQ
Read/Write A one enables pin 24 as an active low interrupt input. Bit 7 must also be set to
configure the VID/IRQ inputs to IRQ mode.
Read/Write A one enables pin 23 as an active low interrupt input. Bit 7 must also be set to
configure the VID/IRQ inputs to IRQ mode.
Read/Write A one enables pin 22 as an active low interrupt input. Bit 7 must also be set to
configure the VID/IRQ inputs to IRQ mode.
Read/Write A one configures the VID/IRQ inputs as Interrupt Inputs. A zero configures the VID/IRQ
inputs as VID inputs only.
25
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