an1871

Application Note 1871
ISL6742EVAL3Z Power Converter 36V to 75V Input, 12V
Output Up to 10A
Introduction
Key Features
The ISL6742EVAL3Z is a standard quarter brick power module
from Intersil. Implemented by the high performance
double-ended PWM controller ISL6742, it is an ideal choice in
applications where performance, space and a pre-bias start-up
are important attributes. Useful features such as the
synchronous rectifier function and the precise average current
OCP contribute to the great performance of the
ISL6742EVAL3Z.
• Industry standard Quarter-brick. 57.9x36.8x15.88mm
• High efficiency, typical up to 93.4% (48V input full load)
• 1500 VDC input to output isolation
• Output overvoltage protection
• Input undervoltage protection
• Hiccup overcurrent protection (based on average current
signal)
• Remote control (On/Off Inhibit)
• Pre-Bias start-up
Equipment and Components
Required
• Input power source up to 75V supply voltage with 200W
power supply ability.
• Electronic load with 150W power sinking ability
• Voltmeters and ammeters (optional)
• At least 300µF/16V output capacitor
July 29, 2013
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1
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
Copyright Intersil Americas LLC 2013. All Rights Reserved.
1-888-INTERSIL or 1-888-468-3774 | Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries.
All other trademarks mentioned are the property of their respective owners.
Application Note 1871
VIN+
VSEN+
VOUT+
DRIVER
HIP2100
VOUTVSEN-
VIN-
DRIVER
OUTB
OUTA
VCC
VIN
ISL89164
ISOLATOR
ISL6742
CONTROLLER
ISL6719
BIAS SUPPLY
OUTAN
OUTBN
FIGURE 1. TYPICAL CIRCUIT DIAGRAM
Terminal Functions
TERMINAL
NAME
NO.
DESCRIPTION
VIN+
1
The positive input voltage node to the module, which is referenced to common ground, VIN-
ON/OFF
2
Applying a high-level signal to this input disables the module’s output and turns off the output voltage. If this pin is left
open-circuit or applying a low-level signal, the module will produce an output whenever a valid input source is applied.
VIN-
3
This is the common ground connection for the input
VO-
4
This is the common ground connection for the VOUT power connection.
VSEN-
5
For remote sense; For optimal voltage accuracy, VSEN- should be connected to the negative of the load directly. It can also be
left disconnected.
Trim
6
This pin can be used to adjust the output voltage above or below output voltage initial setting. To increase the output voltage,
the resistor should be connected between the Trim pin and VSEN- pin while connected between the Trim pin and VSEN+ pin
can decrease the output voltage.
VSEN+
7
For remote sense; For optimal voltage accuracy, VSEN+ should be connected to the positive of the load directly. It can also be
left disconnected.
VO+
8
This is the positive of the output connection for the VOUT power connection.
Getting Started
Using short twisted pair leads for any power connections and
with all loads and power supplies off, refer to Figure 2 for the
proper measurement and equipment setup. The Power Supply
(PS) should not be connected to the circuit until instructed to do
so in the following procedure.
When measuring the input or output voltage ripple, care must be
taken to avoid a long ground lead on the oscilloscope probe.
Measure the input or output voltage ripple by touching the probe
tip directly across the output ceramic capacitor, refer to Figure 3.
2
AN1871.0
July 29, 2013
Application Note 1871
IIN
+ A
IOUT
Vo+
-
+
VIN+
ON/OFF
TRIM
+
V
-
-
+
330µF
+
LOAD
V
VIN
VSEN+
VOUT
+
POWER
SUPPLY
-
+
A -
-
VSEN-
-
VINVo-
FIGURE 2. CONNECTION DIAGRAM
FIGURE 3. OUTPUT RIPPLE MEASUREMENT METHOD
1. External output capacitor with at least 300µF capacitance
should be soldered at the output between VO+ and VO- PIN. A
330µF capacitor is applied in the test.
2. Connect the power supply; electronic load; voltmeters and
ammeters like Figure 2 shows while keeping the power
supply and load power off. For accurate sense voltage, remote
sense is required, solder the wire between VSEN+/VSEN- and
the load as shown in Figure 2. Also, remote sense could be
left open since accuracy here is not important.
3. Turn on the electronic load, making the load sinking a no load.
(Note: Air cooling is preferred when the load is high or the
temperature is higher than +100°C)
Absolute Maximum Ratings
PARAMETER
Supply Voltage,
VIN+ to VINOn/Off
LOW
HIGH
GND - 0.3V
75V
-0.3V
5V
4. Turn on the power supply and set the input voltage to 48V.
Monitor input current, it should be about 60mA. If the input
current exceeds 100mA, turn off the power supply and look
for shorts.
5. Confirm VOUT equals to 12V; Slowly increase the Load on VOUT
to 10A. Verify the VOUT still is 12V.
The board is now ready for operation.
3
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July 29, 2013
Application Note 1871
Electrical Specifications
SYMBOL
TA = +25°C; VIN = 48V; VOUT = 12V; IO = 10A (unless otherwise noted).
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
IO
Output Current
VO = 12V
0
10
A
VIN
Input Range
Over IO range
36
75
V
Output Range
Over IO range, Trim pin open
12
12.032
V
ΔRegline
Line Regulation
Over VIN range
8
mV
ΔRegload
Load Regulation
Over IO range
13
mV
Efficiency
IO = 10A
VIN = 36V
93.65
%
VIN = 48V
93.44
%
VIN = 75V
91.51
%
18.6
mVP-P
13
A
+190/-186
mV
100
µs
VIN increasing
35
V
VIN decreasing
34
Input high voltage, referenced to GND
2.4
V
Input low voltage, referenced to GND
0.5
V
Switching Frequency
Over VIN and IO range
240
kHz
Overvoltage Protection
Over VIN range
14
V
Output Capacitance
Over VIN and IO range
VOUT
η
Vr
VOUT Ripple (Peak to Peak)
20MHz bandwidth, including noise
Iotrip
Overcurrent Threshold
Reset, followed by auto-recovery
ΔVtr
Transient Response
1 A/µs load step, 25 to 75% IO(MAX);
VO over/undershoot
Ttr
UVLO
VINH
VINL
FS
OVP
CO
Load Transient Recovery Time
Undervoltage Lock-out
ON/OFF Control (Pin 2)
300
1100
µF
Remote Control (On/Off)
Output Overcurrent Protection
The on/off function allows the product to be turned on or off by
an external signal. To turn off the converter, apply a high logic
signal referenced to VIN-, like 5V to the on/off pin. The output will
be shut down. While turning on the converter, a low logic signal is
referenced to VIN- (as 0V is applied on this pin or left open it also
could turn on the converter) while a valid power supply is applied
on the input pins.
If the load current is higher than the setting value, 13A, the output
OCP will be functional and get into the hiccup mode to decrease
the power sourcing from the power supply. Due to the unique
function ISL6742 has, the average output current instead of peak
current in most prior products is sensed making the current signal
more accurate.
Input Undervoltage Protection
Pre-bias start condition occurs as a result of an external voltage
being present at the output of a power module prior to its
output becoming active. A prebias can cause problems with
power modules that incorporate synchronous rectifiers. This is
because under most operating conditions, such modules can
sink as well as source output current. This function will assure
that the converter does not sink current during start-up.
Input UVP is integrated in the converter to eliminate the output
voltage re-start when shut down. The output will be shut down
when the input voltage decreases to ~34V and an increase to
~35V would turn on the module.
Output Overvoltage Protection
Output OVP function will be enabled when the output voltage is
higher than 14V, which is a very dangerous situation that could
damage the load circuits. A voltage reference is used for this
function to realize an accurate trigger point, which would avoid
damage when the output is higher than the setting value.
4
Pre-bias Start-up
Trim (Output Voltage Adjust)
The ISL6742 product has an output voltage trim pin. This pin
can be used to adjust the output above or below output voltage
initial setting. When increasing the output voltage, the voltage
at the output sense pins must be kept below the threshold of
the overvoltage protection to prevent shutting down. At an
increased output voltage, the maximum power rating of the
product remains the same, and the max output current must be
decreased correspondingly.
AN1871.0
July 29, 2013
Application Note 1871
+OUT
+OUT
+SENSE
+SENSE
RADJ
LOAD
TRIM
TRIM
LOAD
RADJ
-SENSE
-SENSE
-OUT
-OUT
INCREASE
DECREASE
FIGURE 4. TRIM OUTPUT VOLTAGE
The resistor value for an adjust output voltage is calculated by
using the following equations:
To adjust output voltage upwards:
Connect RTRIM between Pin "VSEN-" and Pin "Trim".
7.9 – 3.16 × Δ%
R TRIM = ----------------------------------------- kΩ
3.16 × Δ%
(EQ. 1)
Example: increase 5%, VOUT = 12V*(1 + 5%) = 12.6V
7.9 – 3.16 × 5%
R TRIM = ----------------------------------------- kΩ = 49kΩ
3.16 × 5%
(EQ. 2)
To adjust output voltage downwards:
Connect RTRIM between Pin "VSEN+" and Pin "Trim".
144 – 197.21 × Δ%
R TRIM = -------------------------------------------------- kΩ
15.17 × Δ%
(EQ. 3)
Example: decrease 5%, VOUT = 12V*(1 - 5%) = 11.4V
144 – 197.21 × 5%
R TRIM = -------------------------------------------------- kΩ = 176.85kΩ
15.17 × 5%
5
(EQ. 4)
AN1871.0
July 29, 2013
ISL6742EVAL3Z Schematic
R55 22k
P7
R85 22k
(2-4):(3-5):(1-6):(8-10):(9-11)
= 4:4:4:3:3
R88 22k
1
SENSE+
R75
10
R86 22k
1
R89 22k
7
4
3
10
9
8
PH
BSC070N10NS3 G
6
1
2 Q4
7
R29 39k C17
1n
D29
2
-
CR2
BAT54S
R26
6.65k
1 E6327
BAS 170W
4
R66
15k
R65
15k
INPUT UVP
D28
1
3
R67
10k
R13
100k
SSEN
BAS 170W E6327
510k
2
R64
10k
C57
3
SS
ISL28213
100n
4
C36
100n
AUTORESTART OCP
DNP:
R57 10k
6
5
100n
2
Do Not Populate
R59
27.4k
1
SENSE-
1
1
SENSE+
R4
100
R19
1k
C40
3300p
VREF
R32
2k
Q17
1
C55
R25
U2
4
100n
1.2k
2
V1 D31 2
PS2801-1
1
D18
R56
100k
BAT54
R83
2M
2
1
DNP
ENSR
100n
C41
1
P6
R21
820
C20
C19
22n
1
Q20
PNP
R77
1n
U4
AS431
R24
3.16k
1K TRIM
SENSE-
47n
Vin=36~75V; Vo=12V@10A 120W
Title
PREBIAS START UP
Intersil Confidential Information
R23
12k
C22
8200p
R20
2k
1
C26
1
BAS 170W E6327
C35
C37
1n
C39
680p
BSS123
D25
1
-
1
U6
R70
AS431 2.4k
SSEN 1
C16
22n
VERR
U38
ISL28113
+
PS2801-1
D30
BAS 170W E6327
R58
1
-
R71
11k
3
VDD
R52
1K
U40A
+
4
30k
OUTPUT OVP
2
2
C15
C28
10n
R62
R82
15k
1
D16
SOT23
Fsw=250kHz
R15
2k
2
3
IOUT
C47
2200p
4
499
R72
1.2k
2
C46
2200p
U5
ISL6742AAZA
5
R63
13k
8
2
R78
SENSE+
2
VREF
499k
R7
MAXIMUM DUTY CYCLE LIMIT
VREF
2
1
C32
4.7u 0805
ISL89164
1
6
ON/OFF
U40B
ISL28213
+
Si8420
1
5
R48
5.1k
8
7
6
5
2
R68
30k
2M
5
C23
GND1 GND2
U39
ENA ENB
/INA OUTA
GND VDD
/INB OUTB
EP
3
100k
100n
R34 C24
20k 1n
VOB
1
2
3
4
9
R47
5.1k
2
8VREF
R69 499k
R60
VREF
VIN+
C56
VIB
6
R50
1.4k
SOT23
BAT54
1
330
VDD1 R3
VREF
10
U3
VERR
1
16 SS
VREF
SS 15
2
R17 10k 3 VERR VADJ 14
VDD 13
CT 4 RTD
OUTA 12
C18 150p 5 CT
OUTB 11
6 FB
7 RAMP OUTAN 10
OUTBN 9
IOUT8 CS
IOUT
GND
Vin
2
R61
1k
R53
1k
VOA
in4148
D34
in4148
D35
7
+12V
SOT23 D17
3
2
100n
R49
1.4k
BAT54
1
330
R40
Q18
1
GND_SIGNAL
2
D14
GA
3
BSS123
R14
1.5k
R16
10k
R39
ISL6719
R74 249K
VREF
2
D13
GB
100n
R73
10k
CR1
BAT54S
470p
5
R80
22u 1210
R6
100
SS
C6
R51
1k
R8
6.49
C7 220p
6
4
100n
VIA
VDD2
D15
CS
C25
1
BAS 170W E6327
COMPA
L3
VCC3
8
U36
VDD1
1
COMPB
VSW_FB
6.49
100p100p
8
3
C29
2
VSW
R5
HIP2100
7
2
C38
C33 C34
2.2
2.2
3
4
R12
9.53k
ENABLE
VDD LO
HB VSS
HO
LI
HS
HI
R37
R36
3
3
VDD1
AUXIN
1
VREF
3
GND
8
7
6
5
1.5mm terminal
P5
SENSE- 1
1
R76 10
3
10
VPWR
ENABLE_N
2
100n
R41
12.7K
BSC070N10NS3 G
GAN
GBN
12.7K
12.7K
R31
R81
2
bas70-04-V-GS08
AUXIN
0
AUXIN
9
C5
100n
R27
100k
R11
220
2
1
C4
GND
4
4.7V
C12
100uF
P4
1
1
CR4
3
C14
1n
1.5mm terminal
C11
22u 1210
22u 1210 22u 1210 22u 1210
3
2
C21
C9 C8
R30
12.7K
D11
Size
B
Date:
ISL6742EVAL3Z Rev. B
Document Number
<Doc>
Sunday , May 13, 2012
Rev
A
Sheet
1
of
1
Application Note 1871
Vin
0.1u 100V
U35
THP
C10
R46
U1
1
2
3
4
VDD1
NPN
0.1u 100V
bas70-04-V-GS08
R45
0
Q19
G 4 R28
100k
D27 100V
R44
0
1
BSC070N10NS3 G
S
T2
1
1
0.1u 100V
C31
1
CR3
P2
D
3
Q2
1 C58 220p
V1
C30
1
1
R87 150k
8
7
6
R43
100k
P3
2
11
PA1005.050NL
8 6 4 5 7
2 Q3
100V
R9
100 0805
D32
BAS 170W E6327
5
1
C3
3.3u 1206
1
D26
C59
100p
2
Q1
3.6k
3
2
1
R42
100k
C2
3.3u 1206
VCC3
1
L2
3
2
1
+48V
8
7
2
+12V
6
5
Vin
L1
1
+12V
D
1VIN+
R33
P8
T1
S
1
BSC070N10NS3 G
G
P1
3.3uH
2
R79 22k
AN1871.0
July 29, 2013
Application Note 1871
Typical Performance Curves
12.035
0.95
0.92
OUTPUT VOLTAGE (V)
OVERALL EFFICIENCY (%)
0.98
0.89
36V INPUT
0.86
0.83
48V INPUT
0.80
0.77
75V INPUT
0.74
0.71
12.030
12.025
12.020
12.015
0.68
0.65
0
2
4
6
8
10
12.010
12
0
2
4
12.028
10
12
12.030
OUTPUT VOLTAGE (V)
12.026
12.024
12.022
12.020
12.018
12.016
12.014
0
2
4
6
8
10
12.025
12.020
12.015
12.010
12.005
12.000
12
0
2
4
6
8
10
12
OUTPUT CURRENT (A)
OUTPUT CURRENT (A)
FIGURE 7. LOAD REGULATION AT 48V INPUT
FIGURE 8. LOAD REGULATION AT 75V INPUT
12.009
12.008
OUTPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
8
FIGURE 6. LOAD REGULATION @ 36V INPUT
FIGURE 5. OVERALL EFFICIENCY vs LOAD CURRENT
12.012
6
OUTPUT CURRENT (A)
OUTPUT CURRENT (A)
12.007
12.006
12.005
12.004
12.003
12.002
12.001
12.000
11.999
30
35
40
45
50
55
60
65
70
75
80
INPUT VOLTAGE (V)
FIGURE 9. LINE REGULATION AT FULL LOAD
7
AN1871.0
July 29, 2013
Application Note 1871
Output Voltage Ripples and Noises
1.00µs
400ns
FIGURE 11. 48V INPUT, FULL LOAD, 18.6mV, CH1, OUTPUT VOLTAGE
FIGURE 10. 36V INPUT, FULL LOAD, 14.2mV, CH1, OUTPUT VOLTAGE
400ns
FIGURE 12. 75V INPUT, FULL LOAD, 40mV, CH1, OUTPUT VOLTAGE
Output Transient Responses
Step Load between 2.5A and 7.5A (25% ~ 75%) at 1A/µs.
2.00ms
FIGURE 13. 36V INPUT, CH1: OUTPUT VOLTAGE, CH4: LOAD
CURRENT
8
2.00ms
FIGURE 14. 48V INPUT, CH1: OUTPUT VOLTAGE, CH4: LOAD CURRENT
AN1871.0
July 29, 2013
Application Note 1871
Output Transient Responses
Step Load between 2.5A and 7.5A (25% ~ 75%) at 1A/µs. (Continued)
2.00ms
FIGURE 15. 75V INPUT, CH1: OUTPUT VOLTAGE, CH4: LOAD CURRENT
Start-up and Shutdown
36V Input
400ms
100ms
FIGURE 16. NO LOAD START-UP, CH1: OUTPUT VOLTAGE, CH2: INPUT
VOLTAGE, CH4: LOAD CURRENT
FIGURE 17. NO LOAD SHUTDOWN, CH1: OUTPUT VOLTAGE,
CH2: INPUT VOLTAGE, CH4: LOAD CURRENT
100ms
FIGURE 18. FULL LOAD START-UP, CH1: OUTPUT VOLTAGE,
CH2: INPUT VOLTAGE, CH4: LOAD CURRENT
9
100ms
FIGURE 19. FULL LOAD SHUTDOWN, CH1: OUTPUT VOLTAGE,
CH2: INPUT VOLTAGE, CH4: LOAD CURRENT
AN1871.0
July 29, 2013
Application Note 1871
Start-up and Shutdown (Continued)
48V Input
100ms
100ms
FIGURE 20. NO LOAD START-UP, CH1: OUTPUT VOLTAGE, CH2: INPUT
VOLTAGE, CH4: LOAD CURRENT
FIGURE 21. NO LOAD SHUTDOWN, CH1: OUTPUT VOLTAGE,
CH2: INPUT VOLTAGE, CH4: LOAD CURRENT
100ms
100ms
FIGURE 22. FULL LOAD START-UP, CH1: OUTPUT VOLTAGE,
CH2: INPUT VOLTAGE, CH4: LOAD CURRENT
FIGURE 23. FULL LOAD SHUTDOWN, CH1: OUTPUT VOLTAGE,
CH2: INPUT VOLTAGE, CH4: LOAD CURRENT
75V Input
100ms
FIGURE 24. NO LOAD START-UP, CH1: OUTPUT VOLTAGE, CH2: INPUT
VOLTAGE, CH4: LOAD CURRENT
10
100ms
FIGURE 25. NO LOAD SHUTDOWN, CH1: OUTPUT VOLTAGE,
CH2: INPUT VOLTAGE, CH4: LOAD CURRENT
AN1871.0
July 29, 2013
Application Note 1871
Start-up and Shutdown (Continued)
100ms
100ms
FIGURE 26. FULL LOAD START-UP, CH1: OUTPUT VOLTAGE,
CH2: INPUT VOLTAGE, CH4: LOAD CURRENT
FIGURE 27. FULL LOAD SHUTDOWN, CH1: OUTPUT VOLTAGE,
CH2: INPUT VOLTAGE, CH4: LOAD CURRENT
Overcurrent Protection and Short Protection
The OCP trigger point is ~13.5A at 36V input, ~13A at 48V input, ~13A at 75V input.
36V Input
40.0ms
1.00µs
FIGURE 28. OVERCURRENT PROTECTION, CH1: OUTPUT VOLTAGE,
CH2: VOLTAGE ON C3, CH3: Vds OF Q4_SR, CH4: LOAD CURRENT
FIGURE 29. ZOOM IN, CH1: OUTPUT VOLTAGE, CH2: VOLTAGE ON C3,
CH3: Vds OF Q4_SR, CH4: LOAD CURRENT
40.0ms
FIGURE 30. SHORT CIRCUIT, CH1: OUTPUT VOLTAGE, CH2: VOLTAGE
ON C3, CH3: Vds OF Q4_SR, CH4: LOAD CURRENT
11
1.00µs
FIGURE 31. ZOOM IN, CH1: OUTPUT VOLTAGE, CH2: VOLTAGE ON C3,
CH3: Vds OF Q4_SR, CH4: LOAD CURRENT
AN1871.0
July 29, 2013
Application Note 1871
Overcurrent Protection and Short Protection
The OCP trigger point is ~13.5A at 36V input, ~13A at 48V input, ~13A at 75V input. (Continued)
48V Input
40.0ms
10.0µs
FIGURE 32. OVERCURRENT PROTECTION, CH1: OUTPUT VOLTAGE,
CH2: VOLTAGE ON C3, CH3: Vds OF Q4_SR, CH4: LOAD
CURRENT
FIGURE 33. ZOOM IN, CH1: OUTPUT VOLTAGE, CH2: VOLTAGE ON C3,
CH3: Vds OF Q4_SR, CH4: LOAD CURRENT
40.0ms
1.00µs
FIGURE 34. SHORT CIRCUIT, CH1: OUTPUT VOLTAGE, CH2: VOLTAGE
ON C3, CH3: Vds OF Q4_SR, CH4: LOAD CURRENT
FIGURE 35. ZOOM IN, CH1: OUTPUT VOLTAGE, CH2: VOLTAGE ON C3,
CH3: Vds OF Q4_SR, CH4: LOAD CURRENT
75V Input
40.0ms
FIGURE 36. OVERCURRENT PROTECTION, CH1: OUTPUT VOLTAGE,
CH2: VOLTAGE ON C3, CH3: Vds OF Q4_SR, CH4: LOAD
CURRENT
12
4.00µs
FIGURE 37. ZOOM IN, CH1: OUTPUT VOLTAGE, CH2: VOLTAGE ON C3,
CH3: Vds OF Q4_SR, CH4: LOAD CURRENT
AN1871.0
July 29, 2013
Application Note 1871
Overcurrent Protection and Short Protection
The OCP trigger point is ~13.5A at 36V input, ~13A at 48V input, ~13A at 75V input. (Continued)
100ms
10.0µs
FIGURE 38. SHORT CIRCUIT, CH1: OUTPUT VOLTAGE, CH2: VOLTAGE
ON C3, CH3: Vds OF Q4_SR, CH4: LOAD CURRENT
FIGURE 39. ZOOM IN, CH1: OUTPUT VOLTAGE, CH2: VOLTAGE ON C3,
CH3: Vds OF Q4_SR, CH4: LOAD CURRENT
Input Undervoltage Protection
Trigger point is ~34V.
200ms
FIGURE 40. CH1: OUTPUT VOLTAGE, CH2: INPUT VOLTAGE, CH4: LOAD CURRENT
Prebias Start-up
Turn off and turn on quickly with no load and large output capacitance condition. The output voltage increases from a 9.3V pre-bias level.Test
with 48V input; no load condition.
200ms
FIGURE 41. CH1: OUTPUT VOLTAGE, CH2: INPUT VOLTAGE
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Application Note 1871
Maximum Duty Cycle Limit
The duty cycle of SR is limited in order to prevent the current flows back from the output at shutdown.
Shutdown at 48V input with no load and the driver signal of SR(Q4) is limited compared with the original one produced by the controller
ISL6742.
10.0µs
FIGURE 42. CH1: OUTPUT VOLTAGE, CH2: OUTBN_IC PIN 10, CH3: GATE SINGLE OF Q4, CH4: LOAD CURRENT
Adaptive Dead Time of SR
Compared with the original signal produced by ISL6742, the driver signal of SR (Q4) is adaptive with the Vds of Q4 and this function makes
better efficiency.
Q4 is turned on after it's Vds decrease to zero and the body diode is conducting.
1.00µs
FIGURE 43. CH2: OUTBN_IC PIN 10, CH3: GATE SINGLE OF Q4, CH4: Vds of Q4_SR
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Output Overvoltage Protection
Output OVP is triggered when the voltage of output is ~14V.
Test the function with open loop and increase the input voltage.
400ms
FIGURE 44. CH1: INPUT VOLTAGE, CH2: OUTPUT VOLTAGE, CH4: LOAD CURRENT
On/Off Function
Enable and disable function. Test at 48V input.
100ms
100ms
FIGURE 45. DISABLE WITHOUT LOAD, CH1: OUTPUT VOLTAGE, CH3:
ON/OFF TERMINAL, CH4: LOAD CURRENT
FIGURE 46. ENABLE WITHOUT LOAD, CH1: OUTPUT VOLTAGE,
CH3: ON/OFF TERMINAL, CH4: LOAD CURRENT
100ms
FIGURE 47. DISABLE WITH FULL LOAD, CH1: OUTPUT VOLTAGE,
CH3: ON/OFF TERMINAL, CH4: LOAD CURRENT
15
100ms
FIGURE 48. ENABLE WITH FULL LOAD, CH1: OUTPUT VOLTAGE,
CH3: ON/OFF TERMINAL, CH4: LOAD CURRENT
AN1871.0
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Application Note 1871
Bill of Materials
ITEM
QTY
REFERENCE
1
2
CR1 CR2
DIODE SCHOTTKY, 30V, 200mA, SOT-23
2
2
CR3, CR4
DIODE SCHOTTKY, DUAL, 70V/100mA SOT-23 Vishay
bas70-04-V-GS08
3
2
C2, C3
CAP, CER, 3.3µF, 50V, X7R 10% 1206
TDK
C3216X7R1H335K
4
2
C4, C6
CAP, CER, 0.1µF, 16V, 10%, X7R, 0603
MURATA
GRM188R71C104KA01D
5
10
C5, C15, C23, C26, C29, CAP, CER, 0.1µF, 16V, 10% X7R, 0402
C35, C36, C55, C56, C57
MURATA
GRM155R71C104KA88D
6
2
C7, C58
CAP, CER, 220pF, 50V, 5%, NP0, 0402
MURATA
GRM1555C1H221JA01D
7
5
C8, C9, C11, C21, C38
CAP, CER, 22µF, 16V, X7R, 1210
TDK
C3225X7R1C226K
8
3
C10, C30, C31
CAP, CER, 0.1µF, 100V, X7R, 0603
MURATA
GRM188R72A104KA35D
9
1
C12
POSCAP, 20V, 100µF, D3L
Sanyo
20TQC100MYF
10
5
C14, C17, C20, C24, C37
CAP, CER, 1000pF, 50V, 10%, X7R, 0402
MURATA
GRM155R71H102KA01D
11
2
C16, C19
CAP, CER, 0.022µF, 16V, 10%, X7R, 0402
MURATA
GRM155R71C223KA01D
12
1
C18
CAP, CER, 150pF, 50V, 5%, NP0, 0402
MURATA
GRM1555C1H151JA01D
13
1
C22
CAP, CER, 8200pF, 50V, 10%, X7R, 0402
MURATA
GRM155R71H822KA88D
14
1
C25
CAP, CER, 470pF, 50V, 5%, NP0, 0402
MURATA
GRM1555C1H471JA01D
15
1
C28
CAP, CER, 10000PF, 16V, 10%, X7R, 0402
MURATA
GRM155R71C103KA01D
16
1
C32
CAP, CER, 4.7µF, 16V, X7R, 0805
MURATA
GRM21BR71C475KA73L
17
3
C33, C34, C59
CAP, CER, 100pF, 50V, 5%, NP0, 0402
MURATA
GRM1555C1H101JZ01D
18
1
C39
CAP, CER, 680pF, 250V, 10%, X7R, 1808
MURATA
GA342QR7GD681KW01L
19
1
C40
CAP, CER, 3300pF, 50V, 10%, X7R, 0402
MURATA
GRM155R71H332KA01D
20
1
C41
CAP, CER, 0.047µF, 50V, 10%, X7R, 0402
TDK Corporation
C1005X7R1H473K
21
2
C46, C47
CAP, CER, 2200pF, 50V, 10%, X7R, 0402
MURATA
GRM155R71H222KA01D
22
1
D11
DIODE ZENER, 4.7V, 500MW, SOD-123
Diodes Inc
BZT52C4V7-13-F
23
3
D13, D14, D18
DIODE SCHOTTKY, 30V, SC-79
Infineon Technologies
BAT 54-02V E6327
24
1
D15
DIODE SCHOTTKY, 30V, 200mA, SOT-23
Fairchild Semiconductor
BAT54A
25
2
D16, D17
DIODE SCHOTTKY, 30V, 200mA, SOT-23
Fairchild Semiconductor
BAT54C
26
6
D25, D28, D29, D30, D31, DIODE SCHOTTKY, 70V, 70mA, SOD-323
D32
Infineon Technologies
BAS 170W E6327
27
2
D26, D27
DIODE SCHOTTKY, 1A, 100V, SMA
vishay
SS1H10-E3/61T
28
2
D34, D35
DIODE SWITCH, 100V, 400MW, SOD123
Diodes
1N4148W-7-F
29
1
L1
INDUCTOR SHIELD, PWR, 1µH SMD
Pulse
pg0083.102nl
30
1
L2
INDUCT PWR, 3.3µH SMD
Pulse
PG0138.332NL
31
1
L3
INDUCT FILTER, 220µH SMD
coilcraft
DO1605T-224MLC
32
6
P1, P2, P3, P5, P6, P7
1mm Power Terminal
ZRX Inc
CZ118
33
2
P4, P8
1.5mm Power Terminal
ZRX Inc
CZ117
34
4
Q1, Q2, Q3, Q4
MOSFET, N-CH, 100V, 90A, TDSON-8
Infineon Technologies
BSC070N10NS3 G
35
2
Q17, Q18
MOSFET, N-CH, 100V, 150mA, SOT-23
NXP Semiconductors
BSS123 215
36
1
Q19
TRANS, NPN, LP, 100mA, 45V, SOT23
ON Semiconductor
BC847ALT1G
37
1
Q20
TRANSISTOR, GP, PNP, AMP, SOT-23
Fairchild Semiconductor
MMBT3906
38
3
R3, R75, R76
RES, 10.0Ω, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-0710RL
16
DESCRIPTIONS
MFG
Fairchild Semiconductor
MFG PART NUMBER
BAT54S
AN1871.0
July 29, 2013
Application Note 1871
Bill of Materials (Continued)
ITEM
QTY
REFERENCE
39
2
R4, R6
RES, 100Ω, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-07100RL
40
2
R5, R8
RES, 6.49Ω, 1/16W, 1%, 0402, SMD
Vishay/Dale
CRCW04026R49FKED
41
1
R7
RES, 499Ω, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-07499RL
42
1
R9
RES, 100Ω, 1/8W, 1%, 0805, SMD
Yageo
RC0805FR-07100RL
43
1
R11
RES, 220Ω, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-07220RL
44
1
R12
RES, 9.53kΩ, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-079K53L
45
7
R13, R27, R28, R42, R43, RES, 100kΩ, 1/16W, 1%, 0402, SMD
R56, R80
Yageo
RC0402FR-07100KL
46
1
R14
RES, 1.50kΩ, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-071K5L
47
3
R15, R25, R32
RES, 2.00kΩ, 1/16W, 1%, SMD, 0402
Yageo
RT0402FRE072KL
48
6
R16, R17, R57, R64, R67, RES, 10.0kΩ, 1/16W, 1%, 0402, SMD
R73
Yageo
RC0402FR-0710KL
49
6
R19, R51, R52, R53, R61, RES, 1.00kΩ, 1/16W, 1%, 0402, SMD
R77
Yageo
RC0402FR-071KL
50
2
R20, R72
RES, 1.20kΩ, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-071K2L
51
1
R21
RES, 820Ω, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-07820RL
52
1
R23
RES, 12.0kΩ, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-0712KL
53
1
R24
RES, 3.16kΩ, 1/16W, 1%, SMD, 0402
Yageo
RT0402FRE073K16L
54
1
R26
RES, 6.65kΩ, 1/16W, 1%, SMD, 0402
Yageo
RT0402FRE076K65L
55
1
R29
RES, 39.0kΩ, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-0739KL
56
4
R30, R31, R41, R81
RES, 12.7kΩ, 1/16W, 1%, SMD, 0402
Yageo
RT0402FRE0712K7L
57
1
R33
RES, 3.60kΩ, 1/16W, 1%, SMD, 0402
Yageo
RT0402FRE073K6L
58
1
R34
RES, 20.0kΩ, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-0720KL
59
2
R36, R37
RES, 2.20Ω, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-072R2L
60
2
R39, R40
RES, 330Ω, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-07330RL
61
3
R44, R45, R46
RES, 0.0Ω, 1/16W, 0402, SMD
Yageo
RC0402JR-070RL
62
2
R47, R48
RES, 5.10kΩ, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-075K1L
63
2
R49, R50
RES, 1.40kΩ, 1/16W, 1%, SMD, 0402
Yageo
RT0402FRE071K4L
64
6
R55, R79, R85, R86, R88, RES, SMD, 1/2W, 22kΩ, J 1206
R89
WALSIN
WF12P223JTL
65
1
R58
RES, 510kΩ, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-07510KL
66
1
R59
RES, 27.4kΩ, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-0727K4L
67
2
R60, R83
RES, 2MΩ, 1/16W, 1%, 0402, SMD
Vishay/Dale
CRCW04022M00FKED
68
2
R62, R69
RES, 499kΩ, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-07499KL
69
1
R63
RES, 13.0kΩ, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-0713KL
70
3
R65, R66, R82
RES, 15.0kΩ, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-0715KL
71
2
R68, R78
RES, 30.0kΩ, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-0730KL
72
1
R70
RES, 2.40kΩ, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-072K4L
73
1
R71
RES, 11.0kΩ, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-0711KL
74
1
R74
RES, 249kΩ, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-07249KL
75
1
R87
RES, 150kΩ, 1/16W, 1%, 0402, SMD
Yageo
RC0402FR-07150KL
17
DESCRIPTIONS
MFG
MFG PART NUMBER
AN1871.0
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Application Note 1871
Bill of Materials (Continued)
ITEM
QTY
REFERENCE
DESCRIPTIONS
MFG
MFG PART NUMBER
76
1
T1
Main Transformer 4:4:4:3:3
WE-Midcom
midcom_750341282
77
1
T2
XFRMR CURR SENSE, 0.50MH, 1:50, SMD
Pulse
PA1005.050NL
78
1
U1
IC, MSFT DVR HALF-BRG, 100V, 8-SOIC
Intersil
HIP2100IB
79
2
U2, U5
OPTOISOLATOR, 1CH, TRANS OUT, 4SSOP
NEC
PS2801C-1-F3-A
80
1
U3
IC, CTRLR, PWM, DOUBLE-ENDED, SSOP16
Intersil
ISL6742AAZA
81
2
U4, U6
IC, REG ADJ ZENER SHUNT, SOT23-3
BCD
AS431ANTRE1
82
1
U35
IC, REG LINEAR ADJ 9-DFN
Intersil
ISL6719ARZ
83
1
U36
IC, ISOLATOR, 2CH, 5.5V, 8-SOIC
Analog Devices Inc
SI8420AB-D-IS
84
1
U38
IC, OPAMP, GP RRIO, 2MHz SOT23-5
Intersil
ISL28113FHZ-T7
85
1
U39
MOSFET DRIVER, 2CH, 5.0V, 6A 8SOIC
Intersil
ISL89164FBEBZ
86
1
U40
IC, OPAMP, GP, RRIO, 2MHz, DUAL 8MSOP
Intersil
ISL28213FUZ
PCB Layout
FIGURE 49. ASSEMBLY TOP
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Application Note 1871
PCB Layout (Continued)
FIGURE 50. ASSEMBLY BOTTOM MIRRORED
FIGURE 51. TOP LAYER
19
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Application Note 1871
PCB Layout (Continued)
FIGURE 52. MID 1 LAYER
FIGURE 53. MID 2 LAYER
20
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Application Note 1871
PCB Layout (Continued)
FIGURE 54. BOTTOM LAYER
Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without notice. Accordingly, the reader is
cautioned to verify that the Application Note or Technical Brief is current before proceeding.
For information regarding Intersil Corporation and its products, see www.intersil.com
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