Quick Start Guide for Demo Board DC377B-A
The DC377B-A demo board features the LTC3716 IC, an IMVP2 compatible 2-phase power
supply for Intel P3-M processor (Tualatin). The input is 8 to 21V. The output is programmed by
the IMVP2 5-bit VIDs (jumpers on the board). The maximum output current is 25A.
Jumper Assignments
The jumpers on the demo board are listed below with their corresponding settings. The quick start
procedure below also provides specific jumper settings—be sure to follow the instructions
carefully.
Jumper Position
Function On Off
VID0 VID0=0 VID0=1
VID1 VID1=0 VID1=1
VID2 VID2=0 VID2=1
VID3 VID3=0 VID3=1
VID4 VID4=0 VID4=1
VRON high low
DSPLP# high low
DPRSLPVR high low
GMUXSEL high low
DLC ON Dynamic Load Test Circuit shut off Dynamic Load Test Circuit turned on
Jumper Position
Function
Leftmost Rightmost Left Off
VBIAS Onboard 3.3V bias
is used
External 3.3V bias is
used
Do not leave off!
FCB FCB=0 FCB=2V FCB=5V
DC377B-A Quick Start Guide Page 1 of 3
Quick Start Procedure
Refer to Figure 1 for proper measurement equipment setup and follow the procedure below:
1. Set the jumpers on the board as follows:
VRON DPSLP# DPRSLPVR GMUXSEL
OFF ON OFF ON
VID0 VID1 VID2 VID3 VID4
OFF OFF OFF ON ON
DLC ON
ON
VBIAS
E
FCB
L
2. Apply input voltage 7~24V across the VIN+ and VIN– terminals.
3. Apply +3.3V logic voltage across +3.3V and SGND terminals.
4. Apply 5V across EXTVCC and SGND terminals if needed.
5. Select VID code using the jumpers VID0–VID4.
6. Select the GMUXSEL/DPRSLPVR/DPSLP# combination using the appropriate jumpers.
7. Replace the VRON jumper
8. Apply the test load across VCC+ and VCC–. Do not exceed a 25A load.
Transient Test
This demo board has a built-in dynamic load test circuit. To test load transients, review Figure 1
and follow this procedure:
1. Shut down the converter by removing the VRON jumper.
2. Apply ±12V supply to the +12V, PGND and –12V terminals.
3. To monitor load current waveforms, connect an oscilloscope to J5 (BNC terminal).
4. Replace the VRON jumper.
5. Remove the DLC ON (Dynamic Load Circuit) jumper.
6. Tune R41, R43 and R39 to program the step amplitude, up-slope and down-slope of the load
step, respectively.
DC377B-A Quick Start Guide Page 2 of 3
DC377B-A Quick Start Guide Page 3 of 3
FRONT OF DEMO BOARDFRONT OF DEMO BOARD
VIN–
VIN+
BACK OF DEMO BOARD
VCC–
VCC+
–
+
–
+
–
+
+
–
J5
VID0
VID1
VID2
VID3
VID4
DLC ON
DPSLP#
VRON GMUXSL
DPRSLPVR
+–
+–
+–
'SCOPE FOR
MONITERING LOAD
TRANSIENT TEST
+3.3V SGND
VBIAS FCB
I E L H
EXTVCC PGOOD PGND +12V –12V
LOAD
+
–
+
–
DYNAMIC LOAD TEST CIRCUIT
R39
R41 R43
2 PHASE MOBILE CPU VRM
LTC3716
DC377B-A or B
(408) 432-1900
Figure 1. Proper Measurement Equipment Setup
