NCV8675DS50GEVB_TEST_PROCEDURE.PDF - 223.0 KB

Test Procedure for the NCP8675 Evaluation Board
7/18/2007
Required Equipment:
-Resistive Load
-2 Multimeters
-One NCV8675 Demo Board
-DC Power Supply
NCV8675 Demo Board
I
Cin
+
DC Voltmeter
Vin
Vout
NCV8675
Reset
Delay
O
DC Power Supply
Cout
Cdelay
Load
+
-
DC
Voltmeter
Vout
G
Figure 1- Dropout Voltage Test Setup
Dropout Voltage Verification Steps
1. Connect circuit as shown in Figure 1.
2. Set Vin= 13.5 V, Record Vout.
3. Reduce Vin until Vout has dropped by 100mV.
4. Subtract Vout from Vin. Resulting Voltage is Dropout Voltage.
NCV8675 Dropout Voltage vs. Load Current
0.45
0.4
0.35
Dropout Voltage (V)
O
0.3
0.25
0.2
0.15
0.1
0.05
0
0
100
200
Load Current (m A)
300
DC
Ammeter
+
DC
Ammeter
-
+
-
NCV8675 Demo Board
DC Power Supply
Vin
I
Reset
Cin
Vout
NCV8675
Delay
Cdelay
Vout
Figure 2. Quiescent Current Verification Setup
Quiescent Current Verification Steps
1. Connect circuit as shown in Figure 2.
2. Set Vin= 13.5 V.
3. Subtract Output Current from Input Current.
NCV8675 Quiescent Current vs.
Load Current
25
Quiescent Current (mA)
20
15
10
5
0
0
100
200
Load Current (m A)
300
O
Cout
Load
NCV8675 Demo Board
Vin
I
Reset
Cin
Vout
NCV8675
O
DC Power Supply
Delay
O
Cout
Cdelay
+
DC Voltmeter
Load
DC
Voltmeter
Vout
G
Figure 3. Output Voltage Verification Setup
Output Voltage Verification Steps
1. Connect circuit as shown in Figure 3.
2. Set output load to 100 Ohms, Set Vin= 0 V, Record Vout.
3. Increase Vin, measure Vout.
NCV8675 Vin Vs. Vout
6
Output Voltage (V)
5
4
3
2
1
Load = 100 Ω
0
0
+
-
10
20
30
Input Voltage (V)
40
Oscilloscope
Ch 1
Ch 2
NCV8675 Demo Board
Vin
I
Cin
NCV8675
Reset
Vout
Delay
Cdelay
Vout
G
Figure 4: Reset Delay Verification Setup
Reset Delay Verification Steps
1. Connect circuit as shown in Figure 4.
2. Set Vin= 0 V.
3. Increase Vin from 0 V to 14 V.
Reset
Delay
Time
Delay
O
DC Power Supply
Cout
Load