INTERSIL ISL9441

ISL9440CEVAL1Z: Triple PWM Step-Down
Synchronous Buck Controller and One LDO
®
Application Note
June 30, 2009
ISL9440CEVAL1Z Evaluation Board
AN1482.0
TABLE 1. FEATURES OF ISL944xx FAMILY
The ISL9440CEVAL1Z evaluation board features the
ISL9440C. The ISL9440C is quad-output controller that
integrates three PWM synchronous buck controllers and one
low-dropout linear regulator controller. The ISL9440C offers
programmable soft-start, independent enable functions and
integrates OV/OC/OT protection. The current mode control
architecture and internal compensation network keep
peripheral component counts minimized. 600kHz switching
frequency can minimize inductor size while the strong gate
driver is able to deliver 12A to each PWM channel.
Table 1 shows the difference in terms of ISL944xx family
features.
EARLY
WARNING
SWITCHING
FREQUENCY
(kHz)
SOFT-STARTING
TIME
(ms)
ISL9440
YES
300
1.7
ISL9440A
YES
600
1.7
ISL9441
NO
300
1.7
ISL9440B
YES
300
PROGRAMMABLE
ISL9440C
YES
600
PROGRAMMABLE
PART
NUMBER
The ISL9440CEVAL1Z is easy to set up to evaluate the
performance of the ISL9440C. Please refer to the “Electrical
Specifications” for typical performance summary.
FIGURE 1. ISL9440CEVAL1Z EVALUATION BOARD
1
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 | Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright Intersil Americas Inc. 2009. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.
Application Note 1482
Electrical Specifications
Recommended operation conditions unless otherwise noted. Refer to schematic and typical
performance curves.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNITS
6.0
12
16
V
VOUT1
0.97
1.00
1.03
V
VOUT2
3.25
3.32
3.4
V
VOUT3
4.85
5.0
5.15
V
VOUT4
2.43
2.50
2.57
V
6
7
A
6
7
A
4
5
A
1.0
A
VIN
All outputs are in regulation
VIN =12V, TA = +25°C, No forced airflow, All three PWM
outputs are fully loaded
PWM1 Rated Current
PWM2 Rated Current
PWM3 Rated Current
LDO Rated Current
R7 = 0Ω, R4 is not populated
0.8
VOUT1 Peak-to-Peak Ripple
VIN = 12V, All three PWM outputs are fully loaded,
Oscilloscope is with full bandwidth
19.8
mVP-P
59.6
mVP-P
66.5
mVP-P
VOUT2 Peak-to-Peak Ripple
VOUT3 Peak-to-Peak Ripple
What’s Inside
Quick Test Guide
The Evaluation Board Kit contains the following materials:
• The ISL9440CEVAL1Z
• The ISL9440B, ISL9440C datasheet
1. Ensure that the circuit is correctly connected to the supply
and electronic loads prior to applying any power. Please
refer to Figure 2 for proper set-up.
• This EVAL KIT document
2. Connect Jumpers J3, J4 and J5 in the ENx positions.
Recommended Equipment
3. Turn on the power supply
The following materials are recommended to perform
testing:
4. Adjust input voltage VIN within the specified range and
observe output voltage. The output voltage variation
should be within 3%.
• 0V to 20V Power Supply with at least 10A Source Current
Capability
• Three Electronic Loads Capable of Sinking Current up to 7A
5. Adjust load current within the specified range and
observe output voltage. The output voltage variation
should be within 3%.
• Digital Multimeters (DMMs)
• 100MHz Quad-Trace Oscilloscope
• Signal Generator (for load transient tests)
2
6. Use oscilloscope to observe output voltage ripple and
Phase node ringing. For accurate measurement, refer to
Figure 3 for proper test set-up.
AN1482.0
June 30, 2009
Application Note 1482
V
Io1
+
_
V
LOAD
Vo2
Io2
+
A
+
_
Vo1
+ VIN -
+
_
+
_ A
LOAD
V
A
+
_
V
LOAD
Vo3
Io3
+
A
FIGURE 2. PROPER TEST SET-UP
3. R27, R22 and R25 are 10kΩ resistors for discharging the
MOSFET gates.
OUTPUT
CAP
OUTPUT
OUTPUT
CAP
CAP
OR MOSFET
OR
MOSFET
FIGURE 3. PROPER PROBE SET-UP TO MEASURE OUTPUT
RIPPLE AND PHASE NODE RINGING
Load Transient Circuit Set-up
4. R26, R23 and R24 are current sensing resistors to
monitor the load step. For accurate measurement, please
use 5% tolerance sensing resistor or better. To alleviate
thermal stress, use 0.1Ω or smaller resistance. The
resistance of the sensing resistors sets the current scale
on the oscilloscope.
5. Apply pulse square waveform across R27, R22 or R25.
The duty cycle of the pulse waveform should be small
(<5%) to limit thermal stress on current sensing resistor
and the MOSFETs (M8, M6 or M7)
1. Select a SOIC8 N-Channel MOSFET with VDSS
breakdown > 20V.
6. The amplitude of the clock sets the current step
amplitude. Adjust the clock amplitude and slew rate to set
the current step and slew rate.
2. Install the load transient circuit as indicated on the
schematic. Refer to Figure 4 for detail.
7. Monitor overshoot and undershoot at corresponding
output.
3
AN1482.0
June 30, 2009
Application Note 1482
.
OPT. LOAD TRAN.
OPT
R27
OPT
M8
R26
OPT
FIGURE 4. LOAD TRANSIENT CIRCUIT FOR PWM1
Typical Evaluation Board Performance Curves
90
VIN = 12V, Unless Otherwise Noted.
100
VIN = 9VDC
85
90
75
VIN = 12VDC
EFFICIENCY (%)
EFFICIENCY (%)
80
70
VIN = 16VDC
65
60
55
85
70
65
45
55
1
2
3
4
5
LOAD CURRENT (A)
6
7
8
FIGURE 5. PWM1 EFFICIENCY vs LOAD (VO = 1.0V)
100
VIN = 16VDC
75
60
0
VIN = 12VDC
80
50
40
VIN = 9VDC
95
50
0
1
2
3
4
5
LOAD CURRENT (A)
6
7
8
FIGURE 6. PWM2 EFFICIENCY vs LOAD (VO = 3.3V)
VIN = 9VDC
95
EFFICIENCY (%)
90
VOUT1(AC), 10mV/DIV
VIN = 12VDC
85
80
VIN = 16VDC
75
70
65
60
55
50
0
1
2
3
4
LOAD CURRENT (A)
5
FIGURE 7. PWM3 EFFICIENCY vs LOAD (VO = 5.0V)
4
6
500ns/DIV
FIGURE 8. PWM1 OUTPUT RIPPLE UNDER MAX LOAD
(VIN = 12V, IO1 = IO2 = 6A, IO3 = 4A, FULL
BANDWIDTH)
AN1482.0
June 30, 2009
Application Note 1482
Typical Evaluation Board Performance Curves
VIN = 12V, Unless Otherwise Noted. (Continued)
VOUT3(AC), 50mV/DIV
VOUT2(AC), 50mV/DIV
500ns/DIV
500ns/DIV
FIGURE 9. PWM2 OUTPUT RIPPLE UNDER MAX LOAD
(VIN = 12V, IO1 = IO2 = 6A, IO3 = 4A, FULL
BANDWIDTH)
FIGURE 10. PWM3 OUTPUT RIPPLE UNDER MAX LOAD
(VIN = 12V, IO1 = IO2 = 6A, IO3 = 4A, FULL
BANDWIDTH)
VOUT2(AC, 100mV/DIV)
VOUT1(AC), 50mV/DIV
ISTEP, 2A/DIV
ISTEP, 2A/DIV
50µs/DIV
50µs/DIV
FIGURE 11. PWM1 LOAD TRANSIENT RESPONSE
(LOAD STEP FROM 1.5A TO 4.5A)
FIGURE 12. PWM2 LOAD TRANSIENT RESPONSE
(LOAD STEP FROM 1.5A TO 4.5A)
VOUT1, 1V/DIV
VOUT3(AC), 100mV/DIV
VOUT2, 2V/DIV
VOUT4, 2V/DIV
ISTEP, 1A/DIV
VOUT3, 2V/DIV
50µs/DIV
FIGURE 13. PWM3 LOAD TRANSIENT RESPONSE
(LOAD STEP FROM 1A TO 3A)
5
1ms/DIV
FIGURE 14. SOFT START WAVEFORMS
AN1482.0
June 30, 2009
Schematic
TP1
VIN
VIN+
TP20
1
VIN
1
VIN
VIN
CIN1
VINTP21
1
GND
TP2
100u
25V
OPT. Load Tran.
CIN2
100u
25V
1
VIN-
UG1
Q1
M2
IRF7907
Q2
PH2
UG2
CIN6
10u
25V
10u
25V
CIN3
VO1
1
PH1
L1
1V @ 6A
CO14
CO13
CO12
CO11
10u
6.3V
10u
6.3V
DNP
6.3V
330u
2.0V
LG1
R15
6
M8
Sany o, 2R5TPE330M7
L2
0
0
CL1
820p
R26 DNP
CB1 0.1u
R13 0
R14 0
CL2
820p
CB2 0.1u
1
VO2
TP7
1.8u
RL2
1.2
R16
DNP
R27
DNP
R23 DNP
VO2
LG2
RL1
1.2
OPT. Load Tran.
R22
DNP
M6
TOKO, #919AS-1R8N
Q2
1.0u
1
DNP
10u
25V
TOKO, #919AS-1R0N
TP5
VO1
TP6
Q1
M1
IRF7907
CIN5
CO21
CO22
CO23
CO24
220u
6.3V
DNP
6.3V
DNP
10V
10u
6.3V
3.3V @ 5.0A+1.0A
1
TP8
GND
1
TP19
GND
Sany o, 6TPE220MI
TP3
PGOOD
R2
102K
1%
RST_N
TP4
26
27
25
PHASE2
BOOT2
28
LGATE2
UGATE2
30
29
LGATE1
UGATE1
BOOT1
ISEN3
EN/SS3
LG3
R18 0
R17 0
20
R4 DNP
0.1u
16V
PH3
TOKO, #919AS-2R8M
VO3
L3
Rsen3
18
3.32K
TP9
VO3
1
2.8u
19
RL3
1.2
17
CO31
CO32
CO33
CO34
220u
6.3V
DNP
6.3V
10u
6.3V
DNP
6.3V
5V @ 4A
1
TP10
GND
Sany o, 6TPE220MI
CL3
820p
R20 0
R3
105K
1%
R5 51
C1
0.22u
R12 0
1
Cf f 3
VO2
1u
R19 0
R8 107K 1%
ROC3
200K
FB2
1
2
EN3
Css3
ROC2 200K
M5
DNP
2
100p
FB3
C3
J4
EN3
1
VO3
CB3
R6
20K
1%
10n
Cp3
J5
EN2
Cf f 2 100p
2
TP15
R9 21.5K 1%
1
LDOFB
10n
C2
2.5V @ 1.0A
TP16
GND
Css2
1
CO41
CO42
10u
100u
4.0V
4TPE100MZB
1
2
1
TP14
EN2
3
Enabled
Disabled
3
VO4
3
Enabled
Disabled
DNP
M4
Si4423DY
TP13
EN3
3
R7 0
R24 DNP
Q2
21
1
VO2
R25
DNP
M7
10u
25V
1
RST
PHASE3
OCSET1
33
3.3n
ROC1
100K
FB1
M3
IRF7907
23
22
FB3
Cp1
8
UG3
24
16
2.2n
PAD
Cf f 1
BOOT3
OCSET3
7
1
UGATE3
ISL9440C
EN/SS1
15
6
VIN
EN/SS2
VO1
R1 25.5K 1%
FB2
5
10n
R21 0
14
EN1
LGATE3
13
3
4
PGND
VCC_5V
DNP
CIN4
Q1
ISEN2
PGOOD
OCSET2
2
3
3
TP17
GND
1
2
Css1 35V
VCC5V
SGND
1
Enabled
Disabled
J3
EN1
SVIN
CFIN1
1
12
16V
2
TP12
EN1
ISEN1
11
0.47u
1
LDOFB
CVCC1 4.7u
OPT. Load Tran.
VIN
Rsen2
3.32K
Application Note 1482
10
G4
VIN RFIN1
10
1
PHASE1
Rsen1
1.82K
TP11
Int. VCC
U1
32
16V
31
16V
RPG1
100K
9
1
PGOOD
22p
R10
10K
1%
R11
34K
1%
Cp2
DNP
Title
ISL9440CEVAL1Z EVALUATION BOARD
Size
Date:
Document Number
<Doc>
Monday , May 11, 2009
Rev
B
Sheet
1
of
1
AN1482.0
June 30, 2009
Application Note 1482
TABLE 2. BILL OF MATERIALS
ESSENTIAL COMPONENTS
ITEM
QTY
PART REFERENCE
1
3
CB1, CB2, CB3
0.1µF
CAP Ceramic X5R, 16V, SMD, 0603,
Generic
2
1
CFIN1
0.47µF
CAP Ceramic X5R, 25V, SMD, 0603,
Generic
3
2
CIN1, CIN2
100µF
Alum. Elec. CAP 25V
Panasonic
4
4
CIN3, CIN4, CIN5, CIN6
10µF
CAP Ceramic X5R, 25V, SMD, 1206,
Generic
5
3
CL1, CL2, CL3
820pF
CAP Ceramic X5R, 16V, SMD, 0603,
Generic
6
1
CO11
330µF
POSCAP, 2.0V, SMD, D2E
7
5
CO13, CO14, CO24, CO33,
CO41
10µF
CAP Ceramic X5R, 6.3V, SMD, 0805
8
2
CO21, CO31
220µF
POSCAP, 6.3V, SMD, D2E
6TPE220MI
Sanyo
9
1
CO42
100µF
POSCAP, 4.0V, SMD, B
4TPE100MZB
Sanyo
10
1
CVCC1
4.7µF
CAP Ceramic X5R, 16V, SMD, 0805,
Generic
11
1
Cff1
2.2nF
CAP Ceramic, SMD, 0603,
Generic
12
2
Cff2, Cff3
100pF
CAP Ceramic, SMD, 0603,
Generic
13
1
Cp1
3.3nF
CAP Ceramic, SMD, 0603,
Generic
14
3
Css1, Css2, Css3
10nF
CAP Ceramic, SMD, 0603,
Generic
15
1
C1
0.22µF
CAP Ceramic X5R, 16V, SMD, 0603,
Generic
16
1
C2
22pF
CAP Ceramic, SMD, 0603,
Generic
17
1
C3
1µF
CAP Ceramic, 6.3V,SMD, 0603,
Generic
18
1
L1
1.0µH
SHIELDED INDUCTOR
#919AS-1R0N
TOKO
19
1
L2
1.8µH
SHIELDED INDUCTOR
#919AS-1R8N
TOKO
20
1
L3
2.8µH
SHIELDED INDUCTOR
#919AS-2R8M
TOKO
21
3
M1, M2, M3
Dual N MOSFET, 30V , SOIC8
IRF7907
International Rectifier
22
1
M4
P MOSFET, SOIC8
Si4423DY
Vishay
23
1
RFIN1
10Ω
RESISTOR, SMD, 0805, 10%
Generic
24
3
RL1, RL2, RL3
1.2Ω
RESISTOR, SMD, 0603, 10%
Generic
25
2
RPG1, ROC1
100kΩ
RESISTOR, SMD, 0603,1%
Generic
26
2
ROC2, ROC3
200kΩ
RESISTOR, SMD, 0603,1%
Generic
27
1
RSEN1
1.82kΩ
RESISTOR, SMD, 0603,1%
Generic
28
2
RSEN2, RSEN3
3.32kΩ
RESISTOR, SMD, 0603,1%
Generic
29
1
R1
25.5kΩ
RESISTOR, SMD, 0603,1%
Generic
30
1
R2
102kΩ
RESISTOR, SMD, 0603,1%
Generic
31
1
R3
105kΩ
RESISTOR, SMD, 0603,1%
Generic
32
1
R5
51Ω
RESISTOR, SMD, 0603,1%
Generic
33
1
R6
20kΩ
RESISTOR, SMD, 0603,1%
Generic
34
1
R8
107kΩ
RESISTOR, SMD, 0603,1%
Generic
35
1
R9
21.5kΩ
RESISTOR, SMD, 0603,1%
Generic
36
1
R10
10kΩ
RESISTOR, SMD, 0603,1%
Generic
37
1
R11
34kΩ
RESISTOR, SMD, 0603,1%
Generic
38
1
U1
-
7
VALUE
DESCRIPTION
QUAD OUTPUT CONTROLLER
PART #
2R5TPE330M7
MANUFACTURER
Sanyo
Generic
ISL9440C
Intersil
AN1482.0
June 30, 2009
Application Note 1482
TABLE 2. BILL OF MATERIALS (Continued)
OPTIONAL COMPONENTS OR RESISTOR JUMPERS
ITEM
QTY
REFERENCE
VALUE
39
10
R7, R12, R13, R14, R15, R16,
R17, R18, R19, R20, R21
40
3
CO12, CO22, CO32
DNP
41
2
CO23, CO34
DNP
42
2
Cp2, Cp3
DNP
43
1
M5
DNP
P MOSFET TO-252
44
3
M6, M7, M8
DNP
N MOSFET
45
4
R4, R22, R25, R27
DNP
RESISTOR, SMD, 0603
46
3
R23, R24, R26
DNP
RESISTOR, SMD, 1206
0
DESCRIPTION
PART #
RESISTOR Jumpers, SMD, 0603, 10%
MANUFACTURER
Generic
EVALUATION BOARD HARDWARES
ITEM
QTY
REFERENCE
VALUE
DESCRIPTION
PART #
MANUFACTURER
47
3
J3, J4, J5
-
3 Head Jumper
68000-236HLF
Generic
48
11
TP1, TP2, TP3, TP4, TP6, TP17,
TP11, TP12, TP13, TP14, TP7
-
TEST POINT
5007
Keystone
49
9
TP8, TP10, TP16, TP19, TP21,
TP9, TP5, TP15, TP20
GND
TURRET
1514-2
Keystone
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
8
AN1482.0
June 30, 2009
ISL9440CEVAL1Z PCB Layout
9
Application Note 1482
FIGURE 15. TOP COMPONENTS
FIGURE 16. TOP LAYER
AN1482.0
June 30, 2009
ISL9440CEVAL1Z PCB Layout
(Continued)
10
Application Note 1482
FIGURE 17. SECOND LAYER (SOLID GROUND)
FIGURE 18. THIRD LAYER
AN1482.0
June 30, 2009
ISL9440CEVAL1Z PCB Layout
(Continued)
11
Application Note 1482
FIGURE 19. BOTTOM LAYER (MIRRORED)
FIGURE 20. BOTTOM COMPONENTS (MIRRORED)
AN1482.0
June 30, 2009