Multiple Channel 1°C Temperature Sensors with Beta Compensation
Datasheet
6.9
Anti-parallel Diode Connections
The EMC1414 supports reading two external diodes on the same set of pins (DP2, DN2). These
diodes are connected as shown in Figure 6.1. Due to the anti-parallel connection of these diodes, both
diodes will be reverse biased by a VBE voltage (approximately 0.7V). Because of this reverse bias,
only discrete thermal diodes (such as a 2N3904) are recommended to be placed on these pins.
6.10
External Diode Connections
The EMC1413 / EMC1414 can be configured to measure a CPU substrate transistor, a discrete
2N3904 thermal diode, or an AMD processor diode on the External Diode 1 channel only. For the
EMC1414 the External Diode 2 and External Diode 3 channels are configured to measure a pair of
discrete anti-parallel diodes (shared on pins DP2 and DN2). The supported configurations for the
external diode channels are shown in Figure 6.5.
to
DP1
to
DP1
to DP2 / DN3
to DN2 / DP3
to
DN1
to
DN1
Local
Ground
Typical remote
Anti-parallel connected
discrete NPN transistors
e.g. 2N3904
Typical remote
discrete NPN transistor
e.g. 2N3904
substrate transistor
e.g. CPU substrate
PNP
Figure 6.5 Diode Configurations
SMSC EMC1413 / EMC1414
Revision 1.41 (02-23-12)
DATA2S5HEET
SMSC [ SMSC CORPORATION ]
