EVB-EMC2101 User Manual

3.9.3Remote Diode

The remote diode on board the EMC2101 EVB has a heater and an optional in-line series resistance adjustment. Checking the REC feature of the EMC2101 is accomplished by removing the jumper on JP7. This adds 100 ohms of series resistance to the DN line of the diode connection. To return to 0 ohm series resistance, replace the jumper on JP7.

To heat the diode, place a jumper on JP10. To return to ambient conditions, remove JP10. These remote diode options are summarized in Table 3.4 below.

Table 3.4 Remote Diode Settings

JUMPER

NAME

OPEN

SHORT

 

 

 

 

JP7

REC

Q11 - 100 ohms in

Q11 - 0 ohms in

 

 

DN line (diode remote -)

DN line (diode remote -)

 

 

 

 

JP13

REC

Q12 - 100 ohms in

Q12 - 0 ohms in

 

 

DN line (diode remote -)

DN line (diode remote -)

 

 

 

 

JP10

HEATER

Ambient temp on remote diode

1.0W resistive heater on remote diode (Q12)

 

 

(Q12)

 

 

 

 

 

This EVB also allows for an off-board diode to be tested (see Table 3.5). This is done by removing both jumpers on JP8. Then connect Pin 1 to the ‘remote+’ terminal of the remote diode and Pin 3 to the ‘remote-‘ terminal of the remote diode. Make sure a common ground exists between the remote diode (GPU, etc.) and the EMC2101 EVB. Also ensure that the remote diode is properly biased according to the diode manufacture.

Table 3.5 Remote Diode Configurations

CONFIGURATION

JUMPER

PIN 1

 

PIN 2

PIN 3

 

PIN 4

 

 

 

 

 

 

 

 

On-board diode (Q11)

JP9

short / DP

 

short / DN

 

 

 

 

 

 

 

 

Off-board diode (CPU,

JP9

remote + / DP

 

open

remote - / DN

 

open

GPU, etc.)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

On-board diode (Q12)

JP12

short / DP

 

short / DN

 

 

 

 

 

 

 

 

Off-board diode (CPU,

JP12

remote + / DP

 

open

remote - / DN

 

open

GPU, etc.)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A unique feature of the EMC2101-R device is the ability to start in one of several different configurations based on the pull up resistor on the ALERT output. The EVB allows the user to quickly evaluate each of the 4 configurations by adjusting JP11 as shown in Table 3.6. When using the auto load via EEPROM, ensure that the Autorefresh Registers is not selected until the loading is complete (less than 1 sec).

Revision 1.5 (12-13-06)

SMSC EMC2101

10