Linear Technology LTC3725 User manual

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
1
LTC3725/LTC3706
DESCRIPTION
Demonstration circuit 888A-B is a high power iso-
lated synchronous forward converter featuring the
LTC3725 and LTC3706. When powered from a 36-
72V input, a single DC888A-B provides an isolated
5V at 40A in a quarter-brick footprint. If higher out-
put current is required, multiple DC888A boards may
be stacked together using on-board connectors for a
complete PolyPhase current sharing solution. The
converter operates at 250kHz and achieves efficiency
up to 93.5% with synchronous output rectifiers.
Secondary-side control eliminates complex optocou-
pler feedback, providing fast transient response with
a minimum amount of output capacitance. Additional
DC888A versions include DC888A-A (3.3V at 50A)
and DC888A-C (12V at 20A). The simple architecture
can be easily modified to meet different input and
output voltage requirements.
Design files for this circuit board are available.
Call the LTC factory.
,LTC and LT are registered trademarks of Linear Technology Corporation.
Table 1. Performance Summary (TA= 25°C)
PARAMETER CONDITION VALUE
Minimum Input Voltage 36V
Maximum Input Voltage 72V
Output Voltage V
OUT
V
IN
= 36V to 72V, I
OUT
= 0A to 40A 5V
Maximum Output Current 200LFM 40A
Typical Output Ripple V
OUT
V
IN
= 48V, I
OUT
= 40A, 250kHz < 60mV
P–P
Output Regulation Over All Input Voltages and Output Currents ±1% (Reference)
Peak Deviation with 20A to 40A Load Step (10A/us) ±250mV
Load Transient Response
Settling Time •50us
Nominal Switching Frequency 250kHz
Efficiency V
IN
= 36V, I
OUT
= 28A 93.5% Typical
Isolation BASIC 1500VDC
Size Component Area x Top x Bottom Component Height 2.3” x 1.45” x 0.4” x 0.075”
OPERATING PRINCIPLES – SINGLE PHASE
The LTC3706 secondary side controller is used on the
secondary and the LTC3725 smart driver with self-
starting capability is used on the primary. When an
input voltage is applied, the LTC3725 (U1 in Figure
15), which is powered through R29 and Q28, begins
a controlled soft-start of the output voltage by switch-
ing MOSFETs Q9 and Q11. As the output voltage be-
gins to rise, the LTC3706 secondary controller is
quickly powered up via D24, Q29, C67, and Q27. The
LTC3706 then assumes control of the output voltage
by sending encoded PWM gate pulses to the
LTC3725 primary driver via signal transformer, T2.
The LTC3725 then operates as a simple driver receiv-
ing both input signals and bias power through T2.
The transition from primary to secondary control oc-
curs seamlessly at a fraction of the output voltage.
From that point on, operation and design simplifies to
that of a simple buck converter. The LTC3706 regu-

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
2
lates by observing the output voltage directly result-
ing in superior output voltage regulation and transient
response.
OPERATING PRINCIPLES – POLYPHASE
The LTC3725 and LTC3706 allow the user to develop
modular power supply “building blocks” that can be
added as power/current requirements increase. Con-
necting two DC888A power supplies in a PolyPhase
configuration has several advantages. By distributing
power across multiple high power/current supplies,
heat is also distributed, reducing individual compo-
nent temperatures. Each parallel module develops
equal output currents so that electrical and thermal
stresses are shared, increasing reliability. Multi-phase
operation and Shared input and output filtering result
in fewer/smaller input/output capacitors and induc-
tors for a given voltage/current ripple or transient re-
sponse.
In PolyPhase systems, one power supply is config-
ured as a “master” and one as a “slave”. The master
communicates switching frequency via the PT+ pin to
FS/SYNC pin of the slave (Figures 19 and 20). The
relative clock phase of each stage is determined by
the slave. The master’s voltage error amplifier’s out-
put (ITH pin) controls the output current of all the
phases via the ITH pin voltage which is distributed to
each slave’s unity-gain differential amplifier.
Several of the signals that are shared between the
master and the slave are of a bidirectional nature. A
fault on either phase can be communicated to the op-
posite phase via the primary side SS/FLT pin inter-
connection or the secondary side RUN/SS intercon-
nection. Sharing Vcc on the secondary side ensures
the master, which initially develops this bias voltage,
and slave power up simultaneously. Each phase then
contributes to the shared Vcc bus. Finally, the input
voltage (Vin) and output voltage (Vout) busses are
interconnected to allow for load sharing.
OPTIONAL POLYPHASE SETUP
Only minor modifications and minimal interconnec-
tions are needed to implement PolyPhase with the
DC888. See component changes list (Figure 18) and
schematics (Figures 21 and 22) for the required elec-
trical changes to master and slave units. After the
modifications are done, the boards are then stacked
one on top of another (Figure 23). J1 and P1 headers
interconnect small signals and E1, E2, E3, and E4
stand offs provide interconnection for the power sig-
nals.
The DC888 was designed primarily to demonstrate
the chipset’s single phase operation and therefore be
further optimized for PolyPhase applications. A small
resistor can be placed between the R76/D27 junction
and C70/U2-16 junction to reduce already small PWM
jitter associated with separate master and slave
ground planes. Another optimization can result from
combining each individual phase’s input/output filter
components into one shared input/output filter.
QUICK START PROCEDURE
Demonstration Circuit 888A-B is easy to set up to
evaluate the performance of the LTC3725 and
LTC3706. Refer to Figure 1 for proper equipment
setup. Follow the procedure below:
NOTE: When measuring the input or output voltage
ripple, care must be taken to avoid a long ground lead
on the scope probe. Measure the output (or input)
voltage ripple by touching the probe tip and probe

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
3
ground directly across the +Vout and –Vout (or +Vin
and –Vin) terminals. See 0 for proper scope probe
technique.
1. The optional input LC filter stage (C2/L5) lowers ac
input rms current. A power supply’s complete in-
put filter must have output impedance that is less
than the converter input impedance to assure sta-
bility. This may require a damping impedance. (See
Linear Technology Application Note AN19 for a
discussion of input filter stability.) A source with a
50mOhm or higher ESR at the filter resonant fre-
quency is one way of providing damping for the fil-
ter elements provided on the DC888A. For bench
testing, adding an 82uF electrolytic capacitor such
as a Sanyo 100MV82AX to the input terminals will
provide suitable damping and ripple current capa-
bility. The values selected have a filter resonant
frequency that is below the converter switching
frequency, thus avoiding high circulating currents
in the filter.
2. Set an input power supply to a voltage of 36V.
Make sure that it is capable of 36V to 72V at a cur-
rent supplying capability of at least 8A per number
of phases being tested. Then, turn off the supply.
3. With power off, connect the supply to the input
terminals +Vin and –Vin.
a. Input voltages lower than 36V can keep the con-
verter from turning on due to the undervoltage
lockout feature of the LTC3725.
b. If efficiency measurements are desired, an am-
meter capable of measuring at least 8Adc per
phase can be put in series with the input supply
in order to measure the DC888A-B’s input cur-
rent.
c. A voltmeter with a capability of measuring • 72V
can be placed across the input to get an accurate
input voltage measurement.
4. Turn on the power at the input.
NOTE: Make sure that the input voltage •72V.
5. Check for the proper output voltage of 5V.
6. Turn off the power at the input.
7. Once the proper output voltages are established,
connect a variable load capable of sinking 40A per
phase at 5V to the output terminals +Vout and –
Vout. Set current to 0A.
a. If efficiency measurements are desired, an am-
meter or a resistor current shunt that is capable
of handling at least 40Adc per phase can be put
in series with the output load in order to meas-
ure the DC888A-B’s output current.
b. A voltmeter with a capability of measuring at
least 5V can be placed across the output termi-
nals in order to get an accurate output voltage
measurement.
8. Turn on the power at the input.
NOTE: If there is no output, disconnect the load to
verify that the load is not set too high.
9. Once the proper output voltage is established, ad-
just the load within the operating range and ob-
serve the output voltage regulation, ripple voltage,
efficiency and other desired parameters.

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
4
Figure 1. Proper Measurement Equipment Setup
VIN
GND
Figure 2. Measuring Input or Output Ripple

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
5
MEASURED DATA
Figures 3 through 14 are measured data for a typical DC888A-B. Figures 15 through 23 consist of schematics, bill of
materials, and a picture.
Figure 3. Efficiency
Figure 4. Output Voltage Ripple (48Vin, 40A, Single Phase)

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
6
Figure 5. Load Transient Response (48Vin, 20A to 40A to 20A at 10A/us, Single Phase)
Figure 6. Loop Response (48Vin, 4A & 40A, Single Phase)

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
7
Figure 7. Turn-on (48Vin, 40A, Single Phase)
Figure 8. Turn-on (48Vin, 80A, PolyPhase)

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
8
Figure 9. Transient Sharing of Inductor Current (48Vin, 30A to 60A, PolyPhase)
Figure 10. Transient Sharing of Inductor Current (48Vin, 60A to 30A, PolyPhase)

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
9
Figure 11. Temp Data (48Vin, 40A, 200LFM airflow – top)
Figure 12. Temp Data (48Vin, 40A, 200LFM airflow – bottom)

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
10
Figure 13. Temp Data (48Vin, 36A, 0LFM airflow – top)
Figure 14. Temp Data (48Vin, 36A, 0LFM airflow – bottom)

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
11
Figure 15. Single Phase Schematic
Vaux
Vsg
D2
CMPSH1-4
R3
100
DA2318-ALC
-VOUT
C101
470pF
-VOUT
R23
6.8 1/4W
T1
PA0954(4:4:1:1)
72
4
11
3 8
10
5 6 1
C100
150pF
-Vin
Q24
A
VCC
Vaux
R84
1k
C71
1uF
C83
10pF
C72
0.1uF
LTC3706EGN
U2
7
2
20
6
12
16
15
1
24
22 21
14
13
8
4
23
19
18
3
17
5
10 11
9
ITH
FG
SW
FB
GND
IS+
IS-
SG
VCC
PT+
PT-
SLP
FS/SYNC
RUN/SS
MODE
PGND
VIN
NDRV
PGOOD
REGSD
PHASE
VS+
VS-
VSOUT
R24
6.8 1/4W
C29
10nF
+Vin
R82
150
D
C70
3.3n
FMMT619
Q32
Q23
R66
100K
+Vout
R53
12
Vsg
R63
100K
L5
0.68uH
Q28
FDC2512
L1
100uH
L6
PA1382.650
B
-VOUT
NOTE:
C2-C5 2.2uF,100V Murata GRM32ER72A225K
L5 VISHAY IHLP2525CZERR68M01
T2 Pulse PA1954NL
D29
BAS21
Q14
C30
2.2nF
250V
IS+
C2
2.2uF
100V
A
R51
6.8
1/4W
C79
3.3n
R69
110K
C51
2.2n
100V
-VOUT
T3
CT02-100
1 2
34
R68
9.1K
SG
VCC
C55
1nF
C3-C5
3 X 2.2uF
100V
C24
1uF
T4
R46
604
C27
100pF
R18
365K
R79
68K
Q25
FMMT718
+VOUT
C78
10nF
Q30
2N7002
3
R75
510
Q27
FCX491A
SG
R78
750
Si7336ADP
C86
68pF
-VOUT
Q8
Si7450DP
Q15
Q11
Si7336ADP
R80
100K
Q29
Si2303BDS
R101
100
1
SW
VCC
R76
8.06
-VOUT
FMMT718
Q26
C66
1.5n
200V
6
IS+
R52
6.8
1/4W
B
D26
CMPSH1-4
LTC3725EMSE
U1
3
8
9
10
7
2
4 5
1
6
11
NDRV
VCC
VSLMT
IS
GATE
SSFLT
FB/IN+
FS/IN-
ULVO
PGND
GND
SW
R22
15.0K
4
C34
22n
D1
CMPSH1-4
C85
0.1uF
R81
150
-VOUT
-Vout
C69
2.2n
100V
R48
15m
1.5W
+VOUT
C77
2.2uF
+
C31, C33, C68
PSLV0J227M12
6.3V
220u
C67
10uF
25V
-VOUT
C
C84
0.1uF
Q31
MMBT2907A
Q9
D24
CMPSH1-4
D27
BAS21
Q13
R58
5.1K T2
8 1
6 3 4 5
Q12
-VOUT
R56
100
C75
100p
5Vo@40A
-VOUT
R41
4.42K
R29
100K
36V-72Vin

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
12
Figure 16. Full Single Phase Schematic
C34
*
Q15
4
5
23 678
1
9.1K
R101
100
HAT2244WP
R108
*
L1
100uH
R70
0
R79
68K
6.8
-VOUT
C71
1uF
R72
OPT
PA1494.242470pF
C66
*
200V
R51
*
1/4W
-VOUT
E7
C33
P1-1
1
0
R56
100
0.015
B
R49
0
47pF
Vaux
SG
J1-6
6
P1-7
7
PA1382.650
L6
240
J1-8
8
+
C68
*
C70
*
Q31
MMBT2907A
R41
0.010
R74
OPT
R24
*
1/4W
R107
*
R53
12
-Vout
SSP
B
P1-3
3
C75
-VOUT
36V
A
T4
MMBZ5258B
Vout/Iout
-VIN
opt.
C34
opt.
BAS21
0.015
J1-2
2
R23
*
1/4W
4.7uF
Q23,Q24
-VOUT
C67
*
25V
D30
*
NOTE:
C2-C5 2.2uF,100V Murata GRM32ER72A225K
L5 VISHAY IHLP2525CZERR68M01
T2 Pulse PA1954NL
-VOUT
D1
CMPSH1-4
T1
*
72
4
11
3 8
10
5 6 1
C83
10pF
TO CONFIGURE
11.5K
opt.
R68
*
R102
*
750
C81
opt.
R48
*
1.5W
opt.
C55
1nF
P1-11
11
FMMT718 Q26
C5
100V
2.2uF
J1-1
1
C3
2.2uF
100V
2.2K
PA0955(6:6:2:1)
R66
100K
FOR POLYPHASE VCC
Q12
4
5
23 678
1
-VIN
+
03.3V@50A
E3
Q27
FCX491A
1
2 3
C101
470pF
Si7336ADP
+VOUT
R22
15.0K
Si7450DP
J1-4
4
C29
10nF
C51
*
100V
PA1382.650
10uF
J1-3
3
C69
*
100V
E8
TO CONFIGURE
C
C30
2.2nF
250V
-
1.5nF
opt.DC888A-A
-VOUT
D31
*
220uF, 6.3V
SW
T3
CT02-100
1 2
34
Q8
Si7450DP
*
4
5
2 3 678
1
R76
*
R59
OPT
Si7450DP
D27
BAS21
22uF
PA0950(6:6:1:1)
C67
C4
100V
2.2uF
C
-VOUT
680pF
opt.
DC888A-B
-VOUT
T4 connection for A-B & A-C
2.74K
Vaux
C74
OPT
IS+
-VOUT
Q24
4
5
23 678
1
1.0K
Q8
C75
*
9.1K
VERSION TABLE
3.3nF
C72
0.1uF
36V-72Vin
SSS
1.5nF
330
VERSION
Si7336ADP
Q30
2N7002
1
2 3
R71
OPT
+
C33
*
VCC
+
C31
*
R63
100K
B
R82
150
R29
100K
Q13
*
4
5
23 678
1
opt.
10nF
Q23
4
5
23 678
1
R108
C86
68pF
R46
604
P1-10
10
SYNC
3
C66
39012V@20A
D26
CMPSH1-4
R73
OPT
C79
*
C77
2.2uF
opt.
R84
*
R78
D
FOR POLYPHASE
J1-5
5
R69
110K
+VOUT
LTC3706EGN
U2
7
2
20
6
12
16
15
1
24
22 21
14
13
8
4
23
19
18
3
17
5
10 11
9
ITH
FG
SW
FB
GND
IS+
IS-
SG
VCC
PT+
PT-
SLP
FS/SYNC
RUN/SS
MODE
PGND
VIN
NDRV
PGOOD
REGSD
PHASE
VS+
VS-
VSOUT
J1-7
7
T2
8 1
6 3 4 5
*
3.3nF
R107
R81
150
-ITH
1
3.3nF
7.50
5.0V@40A
P1-6
6
68uF, 16V
Q14
*
4
5
23 678
1
D24
CMPSH1-4
C31,C68
opt
Q29
Si2303BDS
1
32
-Vin
C70
IS+
-VOUT
P1-4
4
J1-9
9
Q28
FDC2512
3
4 1
2
5
6
R68 R102
R52
*
1/4W
E2
6
4.7nFDC888A-C
P1-9
9
4.42K
620
VCC
J1-10
10
L6
*
2
4 1 5
J1-11
11
C100
150pF
+Vin
2.2nF
A
R41
*
PA0954(4:4:1:1)
R76
VCC
D2
CMPSH1-4
4
C79
10uF
-VOUT
-VIN
A
Q11
4
5
2 3 678
1
C2
2.2uF
100V
P1-5
5
R62
OPT
C84
0.1uF
+ITH
Q12-Q15
8.06
L5
0.68uH
LTC3725EMSE
U1
3
8
9
10
7
2
4 5
1
6
11
NDRV
VCC
VSLMT
IS
GATE
SSFLT
FB/IN+
FS/IN-
ULVO
PGND
GND
5.1
C27
100pF
opt.
C85
0.1uF
T4
DA2318-ALC
6 4
3 1
+Vout
1.0nF
Q25
FMMT718
D31
Vsg
4.7nF
opt.
R80
100K
R58
5.1K
SG
VCC
C24
1uF
E4
P1-2
2
+VPKS
D30
9.53
D
D29
BAS21
3 1
R75
510
opt.
10
C82
opt.
C78
10nF
E1
R60
OPT
10uF
4.7nF
R48
R64
OPT
Q9
4
5
2 3 678
1
22uF
R67
opt.
T1
0
P1-8
8
Vsg
-VPKS
T4 connection for A-A
220uF, 4V
6.2K
SW
-VOUT
R3
100
*
R23,R24,R51,R52
R78
*
R18
365K
FMMT619
Q32
R84C51,C69
100pF

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
13
Qty Reference Part Description Manufacturer / Part #
REQUIRED CIRCUIT COMPONENTS
1
3 C3,C4,C5 CAP., X7R, 2.2uF, 100V, 20%, 1210 Murata, GRM32ER72A225K
2 C24,C71 CAP., X7R, 1.0uF, 16V 10%, 0805 TAIYO YUDEN, EMK212BJ105KG
1 C27, CAP., C0G, 100pF, 50V, 10%, 0603 AVX, 06035A101KAT2A
2 C29,C78 CAP., X7R, 10nF, 50V, 10%, 0603 AVX, 06035C103KAT2A
1 C30 CAP., X7R, 2.2nF, 250V, 10%, 1812 Murata, GA343QR7GD222KW01L
3 C31,C33,C68 NeoCap., 220uF, 6.3V, 20%, V case NEC Tokin, TEPSLV0J227M(12)12R
1 C34 CAP., X5R, 22uF, 6.3V, 20%, 1206 TDK, C3216X5R0J226M
2 C51,C69 CAP., C0G, 2.2nF, 100V, 5%, 1206 Murata, GRM3195C2A222JA01D
1 C66 CAP., C0G, 1.5nF, 200V, 10%, 1206 AVX, 12062A152KAT2A
1 C67 CAP., X7R, 10uF, 25V, 10%, 1210 Taiyo Yuden, TMK325BJ106KN
1 C70 CAP., X7R, 3.3nF, 50V, 10%, 0603 AVX, 06035C332KAT2A
1 C75 CAP., C0G, 100pF, 25V, 10%, 0603 AVX, 06033A101KAT2A
1 C79 CAP., X7R, 3.3nF, 50V, 10%, 0603 AVX, 06035C332KAT2A
1 C55 CAP., C0G, 1nF, 25V, 10%, 0603 AVX, 06033A102KAT2A
1 C77 CAP., X7R, 2.2uF, 16V, 20%, 1206 AVX, 1206YD225MAT2A
1 C72 CAP., X7R, 0.1uF, 25V, 10%, 0805 AVX, 08053C104KAT2A
1 C83 CAP., C0G, 10pF, 50V, 10%, 0603 AVX, 06035A100KAT2A
2 C84,C85 CAP., X7R, 0.1uF, 50V, 10%, 0603 TDK, C1608X7R1H104K
1 C86 CAP., C0G, 68pF, 25V, 10%, 0603 AVX, 06033A680KAT2A
1 C100 CAP., C0G, 150pF, 25V, 10%, 0603 AVX, 06033A151KAT2A
1 C101 CAP., C0G, 470pF, 25V, 10%, 0603 AVX, 06033A471KAT2A
4 D1,D2,D24,D26 Diode Schottky, CMPSH1-4, 40V, SOT23 CENTRAL SEMI., CMPSH1-4-LTC
2 D27,D29 Diode, BAS21 SOT23 Diodes Inc., BAS21
1 L1 INDUCTOR, 100uH, DO1606T Coilcraft, DO1606T-104MLC
1 L6 INDUCTOR, PLANAR, 0.65uH PULSE, PA1382.650
2 Q11,Q9,Q8 FET, N-CH., Si7450DP, Powerpak SO-8 VISHAY, Si7450DP
6 Q12,Q13,Q14,Q15,Q23,Q24 FET, N-CH., Si7336ADP, Powerpak SO-8 VISHAY, Si7336ADP-T1-e3
2 Q25,Q26 TRANSISTOR, NPN, FMMT718, SOT23 ZETEX, FMMT718
1 Q27 TRANSISTOR, NPN, FCX491A, SOT89 ZETEX, FCX491A
1 Q28 FET, N-CH, FDC2512, SUPERSOT-6 Fairchild, FDC2512_NL
1 Q29 FET, P-CH, 30-V(D-S) SOT-23 VISHAY, Si2303BDS-T1-E3
1 Q30 N-MOSFET, 2N7002 SOT23 Diodes Inc., 2N7002-7-F
1 Q31 TRANSISTOR, PNP, SOT-23 DIODES., MMBT2907A-7-F
1 Q32 TRANSISTOR, NPN, SOT-23 ZETEX, FMMT619
3 R3,R56,R101 RES., CHIP, 100, 1/16W, 5%, 0603 VISHAY, CRCW0603100RJNEA
1 R18 RES., CHIP, 365K, 1/8W, 1%, 0805 VISHAY, CRCW0805365KFKEA
1 R22 RES., CHIP, 15.0K, 1/16W, 1%, 0603 VISHAY, CRCW060315K0FKEA
4 R23,R24,R51,R52 RES., CHIP, 6.8, 1/4W, 5%, 1206 VISHAY, CRCW12066R80JNEA
1 R41 RES., CHIP, 4.42K, 1/16W, 1%, 0603 VISHAY, CRCW06034K42FKEA
1 R48 RES., CHIP, 0.015, 1.5W, 2%, 2512 IRC, LRC-LRF2512-01-R015-G
1 R68 RES., CHIP, 9.1K, 1/16W, 5%, 0603 VISHAY, CRCW06039K10JNEA
1 R76 RES., CHIP, 8.06, 1/16W, 1%, 0805 VISHAY, CRCW08058R06FNEA
1 R78 RES., CHIP, 750, 1/16W, 5%, 0603 VISHAY, CRCW0603750RJNEA

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
14
Figure 17. Bill of Materials (Single Phase)
1 R84 RES., CHIP, 1.0K, 1/16W, 5%, 0805 VISHAY, CRCW08051K00JNEA
1 R29 RES., CHIP, 100K, 1/8W, 5%, 0805 VISHAY, CRCW0805100KJNEA
1 R46 RES., CHIP, 604, 1/16W, 1%, 0603 VISHAY, CRCW0603604RFKEA
1 R53 RES., CHIP, 12, 1/16W, 5%, 0603 VISHAY, CRCW060312R0JNEA
1 R58 RES., CHIP, 5.1K, 1/16W, 5%, 0603 VISHAY, CRCW06035K10JNEA
3 R63,R66,R80 RES., CHIP, 100K, 1/16W, 5%, 0603 VISHAY, CRCW0603100KJNEA
1 R69 RES., CHIP, 110K, 1/16W, 5%, 0603 VISHAY, CRCW0603110KJNEA
1 R75 RES., CHIP, 510, 1/16W, 5%, 0603 VISHAY, CRCW0603510RJNEA
1 R79 RES., CHIP, 68K, 1/8W, 5%, 0603 VISHAY, CRCW060368K0JNEA
2 R81,R82 RES., CHIP, 150, 1/16W, 5%, 0603 VISHAY, CRCW0603150RJNEA
1 T1 TRANSFORMER, PLANAR, 4:4:1:1 PULSE, PA0954
1 T2 TRANSFORMER, PA1954NL PULSE, PA1954NL
1 T3 TRANSFORMER, CT02-100 ICE Components., CT02-100
1 T4 TRANSFORMER, 1.5 : 1 Coilcraft, DA2318-ALC
1 U1 I.C. LTC3725EMSE, MS10E LINEAR TECH., LTC3725EMSE#PBF
1 U2 I.C. LTC3706EGN, SSOP-24GN LINEAR TECH., LTC3706EGN#PBF
ADDITIONAL DEMO BOARD CIRCUIT COMPONENTS
2
1 C2 CAP., X7R, 2.2uF, 100V, 20%, 1210 Murata, GRM32ER72A225K
0 C74(opt) CAP., 0603
0 C81,C82(opt.) CAP., 0603
0 D30 (opt) Diode, SOT23
0 D31 (opt) Diode, SOT23
1 L5 INDUCTOR, 0.68uH, VISHAY, IHLP-2525CZERR68M01 e3
0 Q8(opt) FET, N-CH., SO-8
2 R49,R70 RES., CHIP, 0, 1/16W, 0603 VISHAY, CRCW06030000Z0EA
0 R59,R60.R62,R64,R67,R71
-R74(opt) RES., 0603
0 R102,R107(opt) RES., 0603
1 R108 RES., CHIP, 0, 1/16W, 0603 VISHAY, CRCW06030000Z0EA
2 E1,E2 TESTPOINT, TURRET, .094" MILL-MAX, 2501-2-00-80-00-00-07-0
2 E8,E7 TESTPOINT, TURRET, .061" MILL-MAX, 2308-2-00-80-00-00-07-0
2 E3,E4 STUD PEM, KFH-032-6
4 E3,E4(2 EACH) NUT, BRASS, #10-32 ANY
2 E3,E4 WASHER, STAR #10 BRASS NICKEL ANY
2 E3,E4 Ring, Lug Ring # 10 KEYSTONE 8205
1 J1 HEADER, SMD, single row, 2mm Comm Com, 2SMD1-140/335/180-11G2
1 P1 SOCKET, SMD, single row, 2mm COMM COM, 1309-11G2
Notes:
1. Required Circuit Components are those parts that are required to implement the circuit function
2. Additional Demo Board Circuit Components are those parts that provide added functionality for the demo
board but are or may not be required in the actual circuit.
Figure 17. Bill of Materials (Single Phase) (cont’d)

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
15
Ref
Des
Single
Phase PolyPhase
C29 10nF 4.7nF
C70 3.3nF 15nF
C78 10nF 4.7nF
R71 OPT 0Ω
R72 OPT 0Ω
MASTER
R74 OPT 0Ω
C29 10nF 4.7nF
C70 3.3nF 15nF
C78 10nF 4.7nF
C79 3.3nF open
R41 4.42kΩopen
R46 604Ωopen
R59 OPT 0Ω
R60 OPT 0Ω
R62 OPT 0Ω
R63 100kΩopen
R64 OPT 0Ω
R67 OPT 0Ω
R68 9.1kΩopen
R69 110kΩopen
R70 0Ωopen
SLAVE
R73 OPT 0Ω
Figure 18. Single Phase to PolyPhase Electrical Component Changes

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
16
Figure 19. PolyPhase Master Schematic
-ITH
Q14R76
8.06
R56
100
Vaux
R68
9.1K
C69
2.2n
100V
+ITH (to +ITH SLV)
LTC3706EGN
U2
7
2
20
6
12
16
15
1
24
22 21
14
13
8
4
23
19
18
3
17
5
10 11
9
ITH
FG
SW
FB
GND
IS+
IS-
SG
VCC
PT+
PT-
SLP
FS/SYNC
RUN/SS
MODE
PGND
VIN
NDRV
PGOOD
REGSD
PHASE
VS+
VS-
VSOUT
J1-9
9
-VIN (to SLV)
D
R66
100K
SG
SG
C27
100pF
4
C79
3.3n
Q27
FCX491A
-VOUT (to SLV)
Q11
2
C55
1nF
R75
510
J1-7
7
E2
B
T4
+VPKS
R84
1k
D24
CMPSH1-4
-VOUT
1
P1-9
9
R63
100K
D2
CMPSH1-4
D29
BAS21
3
R29
100K
C83
10pF
R79
68K
A
Q23
L5
0.68uH
Si7336ADP
+Vout (to +Vout SLV)
R82
150
R48
15m
1.5W
L6
PA1382.650
T2
8 1
6 3 4 5
R46 604
C3-C5
3 X 2.2uF
100V
-VOUT
SW
SSS
C100
150pF
R52
6.8
1/4W
Si7336ADP
VCC
1
+VPKS (to +VPKS SLV)
-VOUT
T3
CT02-100
1 2
34
J1-2
2
R22
15.0K
R78
750
LTC3725EMSE
U1
3
8
9
10
7
2
4 5
1
6
11
NDRV
VCC
VSLMT
IS
GATE
SSFLT
FB/IN+
FS/IN-
ULVO
PGND
GND
C51
2.2n
100V
IS+
J1-5
5
T1
PA0954(4:4:1:1)
72
4
11
3 8
10
5 6 1
-VPKS (to -VPKS SLV)
6
+VOUTB
R23
6.8 1/4W
R58
5.1K
C78 4.7nF
R53
12
Vaux
R101
100
5Vo
MASTER
C67
10uF
25V
E4
4
J1-6
6
-VOUT
-VOUT
+ITH
Q29
Si2303BDS
C75
100p
R81
150
Q13
3
1
-Vin (to SLV)
SSS (to SSS SLV)
C86
68pF
R24
6.8 1/4W
-Vout
-VPKS
C77
2.2uF
VCC
C72
0.1uF
E2
E3
R41
4.42K
D1
CMPSH1-4
Q28
FDC2512
P1-6
6
J1-8
8
SSP
Q30
2N7002
C84
0.1uF
Q15
P1-7
7
SW
C71
1uF
D26
CMPSH1-4
SYNC (to SYNC SLV)
P1-11
11
C85
0.1uF
3
J1-11
11
Q9
IS+
-VOUT
C66
1.5n
200V
36V-72Vin
-ITH (to -ITH SLV)
C24
1uF
R18
365K
E1
+VOUT
Vsg
R3
100
Q31
MMBT2907A
C29
4.7n
DA2318-ALC
Q8
Si7450DP
A
FMMT718
Q26
P1-5
5
VCC
4
-Vin
-VOUT
C
+Vin (to SLV)
R80
100K
D27
BAS21
L1
100uH
C34
22n
C30
2.2nF
250V
J1-10
10
+Vin
-VOUT
C2
2.2uF
100V
Q25
FMMT718
-VOUT
P1-1
1
E4
2
J1-1
1
P1-8
8
Q12
Q24
E1
FMMT619
Q32
+Vout
C70
15n
R51
6.8
1/4W
SYNC
-Vout (to -Vout SLV)
Vsg
C101
470pF
-VOUT
P1-10
10
R69 110K
SSP (to SSP SLV)
NOTE:
C2-C5 2.2uF,100V Murata GRM32ER72A225K
L5 VISHAY IHLP2525CZERR68M01
T2 Pulse PA1954NL
+
C31, C33, C68
PSLV0J227M12
6.3V
220u
P1-2
2
E3

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
17
Figure 20. PolyPhase Slave Schematic
P1-2
2
FMMT619
Q32
-VPKS
D24
CMPSH1-4
C2
2.2uF
100V
VCC
E1
R84
1k
SSP (to SSP SLV)
L5
0.68uH
Q28
FDC2512
C24
1uF
-Vout
+Vin
J1-7
7
+VPKS (to +VPKS SLV)
Q14
L6
PA1382.650
T2
8 1
6 3 4 5
R53
12
2
P1-8
8
C101
470pF
-VOUT
IS+
P1-6
6
-Vout (to -Vout SLV)
Si7336ADP
D29
BAS21
T3
CT02-100
1 2
34
R79
68K
SSP
+VPKS
Q11
T4
E4
VCC
Q9
VCC
R22
15.0K
R3
100
R66
100K
E4
J1-6
6
P1-9
9
B
A
C72
0.1uF
J1-2
2
Q8
Si7450DP
4
Q13
C84
0.1uF
E3
-VOUT
P1-1
1
4
2
R80
100K
-VOUT
E2
C86
68pF
-Vin
R58
5.1K
R23
6.8 1/4W
4
C27
100pF
+ITH (to +ITH SLV)
C83
10pF
P1-7
7
C55
1nF
T1
PA0954(4:4:1:1)
72
4
11
3 8
10
5 6 1
1
DA2318-ALC
SLAVE
SG
+Vin (to SLV)
LTC3706EGN
U2
7
2
20
6
12
16
15
1
24
22 21
14
13
8
4
23
19
18
3
17
5
10 11
9
ITH
FG
SW
FB
GND
IS+
IS-
SG
VCC
PT+
PT-
SLP
FS/SYNC
RUN/SS
MODE
PGND
VIN
NDRV
PGOOD
REGSD
PHASE
VS+
VS-
VSOUT
C69
2.2n
100V
R75
510
Si7336ADP
C77
2.2uF
Q29
Si2303BDS
C29
4.7n
R24
6.8 1/4W
-VPKS (to -VPKS SLV)
C
C30
2.2nF
250V
P1-10
10
SSS (to SSS SLV)
-VOUT
-VOUT (to SLV)
C100
150pF
R76
8.06
SYNC (to SYNC SLV)
R56
100
C71
1uF
E2
SG
Q25
FMMT718
Vaux
-VOUT
C85
0.1uF
IS+
-VOUT
+VOUT
D27
BAS21
D2
CMPSH1-4
6
SW
R18
365K
-VOUT
36V-72Vin
-ITH
R48
15m
1.5W
J1-8
8
Q27
FCX491A
1
E1
+
C31, C33, C68
PSLV0J227M12
6.3V
220u
+Vout
Q15
R51
6.8
1/4W
C67
10uF
25V
R81
150
B
J1-9
9
J1-11
11
R82
150
1
L1
100uH
Q30
2N7002
-ITH (to -ITH SLV)
VCC
P1-5
5
-Vin (to SLV)
C51
2.2n
100V
R29
100K
C34
22n
Q31
MMBT2907A
FMMT718
Q26
J1-10
10
P1-11
11
D26
CMPSH1-4
Vaux
Q23
5Vo
Vsg
SSS
NOTE:
C2-C5 2.2uF,100V Murata GRM32ER72A225K
L5 VISHAY IHLP2525CZERR68M01
T2 Pulse PA1954NL
Vsg
3
Q24
A
R101
100
R52
6.8
1/4W
J1-5
5
LTC3725EMSE
U1
3
8
9
10
7
2
4 5
1
6
11
NDRV
VCC
VSLMT
IS
GATE
SSFLT
FB/IN+
FS/IN-
ULVO
PGND
GND
SYNC
-VOUT
C75
100p
+Vout (to +Vout SLV)
+VOUT
R78
750
E3
-VOUT
J1-1
1
C70
15n
3
D1
CMPSH1-4
3
SW
VCC
C78
4.7nF
C66
1.5n
200V
Q12
-VIN (to SLV)
D
-VOUT
+ITH
C3-C5
3 X 2.2uF
100V

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
18
Figure 21. Full PolyPhase Master Schematic
Vsg
J1-11
11
Q24
4
5
23 678
1
J1-2
2
36V
3
SG
P1-4
4
J1-10
10 J1-9
9
C74
OPT
SSS (to SSS SLV)
PA1382.650
D
D31
*
C75
P1-7
7
R68
*
P1-8
8
D24
CMPSH1-4
C101
470pF
5.0V@40A
VCC
C86
68pF J1-3
3
-Vin (to SLV)
3.3V@50A 15nF
P1-6
6
Q31
MMBT2907A
R72
0ohms
C31,C68
opt.
Vsg
J1-5
5
+
C68
*
+
1
-VOUT
SYNC (to SYNC SLV)
12V@20A
SW
opt.
D1
CMPSH1-4
E7
1.0K6.8
C51
*
100V
C66
*
200V
PA0955(6:6:2:1)240
R51
*
1/4W
R22
15.0K
680pF
R41
R63
100K
R48
*
1.5W
6
L6
E3
C70
*
-ITH (to -ITH SLV)
R23,R24,R51,R52
Q23
4
5
23 678
1
T4
DA2318-ALC
6 4
3 1
R49
0
3.3nF
opt
-VOUT
R107
*
C83
10pF
R64
OPT
R46 604
*
Q11
4
5
2 3 678
1
C33 R48
PA1494.242
4
Vout/Iout
R74
0ohms
+ITH (to +ITH SLV)
opt.
LTC3725EMSE
U1
3
8
9
10
7
2
4 5
1
6
11
NDRV
VCC
VSLMT
IS
GATE
SSFLT
FB/IN+
FS/IN-
ULVO
PGND
GND
0.010
C34
SG
C78
4.7nF
+
C31
*
B
E2
T2
8 1
6 3 4 5
Q15
4
5
23 678
1
D27
BAS21
opt.
R102
Vaux
C72
0.1uF
C34
*
C69
*
100V
Si7336ADP
C67 25V
10uF
-
R84
*
R29
100K
+VPKS (to +VPKS SLV)
9.1K
D31
+Vin (to SLV)
9.53
1.0nF
R59
OPT
-VOUT
-VOUT
B
P1-5
5
C100
150pF
P1-3
3
D30
2.2K
A
Q9
4
5
2 3 678
1
C82
opt.
2.2nF
-VIN
R108
*
Q12-Q15
390
MASTER
0
R18
365K
Si7336ADP
R67
opt.
Si7450DP
-VOUT
36V-72Vin
P1-1
1
opt.
-VOUT
4.7nF
PA0954(4:4:1:1)
R76
*
R84
VERSION TABLE
VERSION
NOTE:
C2-C5 2.2uF,100V Murata GRM32ER72A225K
L5 VISHAY IHLP2525CZERR68M01
T2 Pulse PA1954NL
47pF
R78
9.1K
R82
150
D26
CMPSH1-4
R56 100
J1-6
6
C3
2.2uF
100V
opt.
VCC
Q12
4
5
23 678
1
C81
opt.
R68
opt.
10
R107
LTC3706EGN
U2
7
2
20
6
12
16
15
1
24
22 21
14
13
8
4
23
19
18
3
17
5
10 11
9
ITH
FG
SW
FB
GND
IS+
IS-
SG
VCC
PT+
PT-
SLP
FS/SYNC
RUN/SS
MODE
PGND
VIN
NDRV
PGOOD
REGSD
PHASE
VS+
VS-
VSOUT
C51,C69
+VOUT
P1-11
11
E4
R62 OPT
DC888A-C
R53
12
E8
D30
*
10nF
L6
*
2
4 1 5
C
+
C33
*
Q8
C66
4.42K
-VOUT
R66
100K
C75
*
T4 connection for A-A
opt.
SW
R23
*
1/4W
Q28
FDC2512
3
4 1
2
5
6
R73
OPT
R101
100
0
T1
*
72
4
11
3 8
10
5 6 1
T4
2.74K
C
R80
100K
470pF
22uF
-VOUT
L5
0.68uH
J1-4
4
1.5nF
DC888A-A
HAT2244WP
Vaux
R81
150
0.015
IS+
-VOUT
C85
0.1uF
C79
R69
110K
T3
CT02-100
1 2
34
Q29
Si2303BDS
1
32
8.06
620
FMMT718
Q26
C79
*
D2
CMPSH1-4
-VPKS (to -VPKS SLV)
330
VCC
J1-1
1
C2
2.2uF
100V
15nF
10uF
750
R24
*
1/4W
B
C29
4.7nF
E1
P1-2
2
BAS21
Q25
FMMT718
FMMT619
Q32
Q23,Q24
-Vout (to -Vout SLV)
DC888A-B 220uF, 6.3V
C5
100V
2.2uF
0
D
Q27
FCX491A
1
2 3
C71
1uF
R71
0ohms
C70
C77
2.2uF
C4
100V
2.2uF
11.5K
+VOUT
L1
100uH
*
MMBZ5258B
Q13
*
4
5
23 678
1
C27
100pF
P1-10
10
1.5nF
C30
2.2nF
250V
+Vout (to +Vout SLV)
5.122uF
R41
*
Q30
2N7002
1
2 3
C55
1nF J1-7
7
J1-8
8
4.7nF
P1-9
9
R108
D29
BAS21
3 1
R79
68K
4.7nF
-VOUT
6.2K
IS+
C24
1uF
R75
510
R52
*
1/4W
R58
5.1K
R60
OPT
100pF
SSP (to SSP SLV)
68uF, 16V
PA1382.650
R102
*
T4 connection for A-B & A-C
0.015
R78
*
220uF, 4V opt.
opt.
C84
0.1uF
opt.
A
R70
0
-VIN
VCC
7.50
T1
-VOUT
A
PA0950(6:6:1:1)
R76
Q8
Si7450DP
*
4
5
2 3 678
1
-VOUT (to SLV)
Si7450DP
VCC
R3
100
Q14
*
4
5
23 678
1
-VIN (to SLV)

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
19
Figure 22. Full PolyPhase Slave Schematic
L1
100uH
C74
OPT
opt.
P1-2
2
VERSION TABLE
opt.
0.015
0.010
VCC
+
C68
*
J1-9
9
C51
*
100V
C81
opt.
Q12
4
5
23 678
1
SLAVE
22uF
Q8
P1-9
9
R41
*
T3
CT02-100
1 2
34
5.0V@40A
Vaux
C27
100pF
E7
36V
DC888A-A
C51,C69
*
E8
R84
R59
0ohms
-VOUT
J1-7
7
NOTE:
C2-C5 2.2uF,100V Murata GRM32ER72A225K
L5 VISHAY IHLP2525CZERR68M01
T2 Pulse PA1954NL
PA0954(4:4:1:1)
D30
1.0K
-VIN
R64 0ohms
R71
OPT
DC888A-B
C79
*
P1-10
10
220uF, 4V
A
R82
150
D29
BAS21
3 1
R60
0ohms
6.8
T1
D
Vsg
R49
0
D2
CMPSH1-4
R79
68K
opt.220uF, 6.3V
-VOUT
J1-1
1
A
Q8
Si7450DP
*
4
5
2 3 678
1
R72
OPT
BAS21DC888A-C
-VOUT
-VOUT
R48
*
1.5W
470pF
opt.
R108
*
PA0950(6:6:1:1)
-VOUT
2.2nF
C85
0.1uF
R108
Q27
FCX491A
1
2 3
R51
*
1/4W
C101
470pF
Q9
4
5
2 3 678
1
T4
-Vout (to -Vout M STR)
C55
1nF
R69
110K
620
opt.
A
+
opt 1.0nF
Vout/Iout
P1-8
8
R23
*
1/4W
R48
Si7450DP
+Vout (to +Vout MSTR)
VCC
Q31
MMBT2907A
750
-
PA1382.650
Q12-Q15C75
R75
510
C77
2.2uF
15nF
R101
100
0
Q24
4
5
23 678
1
R53
12
MMBZ5258B
Vsg
Q29
Si2303BDS
1
32
-VPKS (to -VPKS MSTR)
T4 connection for A-B & A-C
opt.
36V-72Vin
PA1494.242
0
IS+
390
C4
100V
2.2uF
L6
B
R23,R24,R51,R52
C71
1uF
P1-6
6
D30
*
+VPKS (to +VPKS MSTR)
-VOUT
+VOUT
B
C24
1uF
Q13
*
4
5
23 678
1
L5
0.68uH
12V@20A
Q15
4
5
23 678
1
D1
CMPSH1-4
C34 C66
opt.
10nF
B
R80
100K
R3
100
FMMT718
Q26
+
C33
*
FMMT619
Q32
8.06
VCC
-VOUT
+ITH (to +ITH MSTR)
+VOUT
3
4.7nF
R102
R67
0ohms
C100
150pF
R102
*
C30
2.2nF
250V
LTC3725EMSE
U1
3
8
9
10
7
2
4 5
1
6
11
NDRV
VCC
VSLMT
IS
GATE
SSFLT
FB/IN+
FS/IN-
ULVO
PGND
GND
E1
opt.
C82
opt.
E2
VCC
J1-5
5
J1-10
10
LTC3706EGN
U2
7
2
20
6
12
16
15
1
24
22 21
14
13
8
4
23
19
18
3
17
5
10 11
9
ITH
FG
SW
FB
GND
IS+
IS-
SG
VCC
PT+ PT-
SLP
FS/SYNC
RUN/SS
MODE
PGND
VIN
NDRV
PGOOD
REGSD
PHASE
VS+
VS-
VSOUT
D26
CMPSH1-4
opt.
R62
0ohms
C83
10pF
-ITH (to -ITH MSTR)
D
T2
8 1
6 3 4 5
J1-2
2
1
J1-8
8
R78
T4
DA2318-ALC
6 4
3 1
P1-3
3
C29
4.7nF
PA1382.650
1.5nF
C66
*
200V
P1-5
5
-VOUT
R56
100
R58
5.1K
*
100pF
330
D24
CMPSH1-4
R81
150
R22
15.0K
6
Q28
FDC2512
3
4 1
2
5
6
680pF 7.50
Q23,Q24
opt.
-VOUT
J1-6
6
R52
*
1/4W
-VIN
R84
*
C2
2.2uF
100V
5.1 2.2K
VERSION
D27
BAS21
-VIN (to MSTR)
E4
Q25
FMMT718
R107
Q30
2N7002
1
2 3
4
P1-11
11
C84
0.1uF
L6
*
2
4 1 5
SYNC (to SYNC MSTR)
47pF
R76
Si7450DP
C
Q23
4
5
23 678
1
C75
*
T1
*
72
4
11
3 8
10
5 6 1
J1-3
3
E3
C34
*
3.3V@50A
SG
R73
0ohms
SSP (to SSP MSTR)
R68
*
C70
*
0
C5
100V
2.2uF
P1-4
4
C72
0.1uF
SSS (to SSS MSTR)
Si7336ADP
PA0955(6:6:2:1)
SG
SW
P1-1
1
J1-4
4
R74
OPT
Q11
4
5
2 3 678
1
C67
*
25V
P1-7
7
68uF, 16V
-VOUT
IS+
D31
*
+
C31
*
R46
604
R66
100K
240
0.015
C33
Q14
*
4
5
23 678
1
R24
*
1/4W
R63
100K
VCC
10
Vaux
R29
100K
R76
*
-VOUT (to MSTR)
22uF
R78
*
R18
365K
C3
2.2uF
100V
T4 connection for A-A
SW
-Vin (to MSTR)
9.53
C70
opt.10uF
C
C78
4.7nF
D31
HAT2244WP
Si7336ADP15nF
J1-11
11
R107
*
-VOUT
R70
0
C86
68pF
+Vin (to MSTR)
1.5nF
C69
*
100V
C31,C68

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 888A-B
36V-72VIN, ISOLATED SYNCHRONOUS FORWARD
20
Figure 23. Picture of two DC888A’s configured for PolyPhase