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Application Note 1907
ISL8216MEVAL1Z Evaluation Board User’s Guide
Description
Recommended Equipment
The ISL8216M is a simple and easy to use, high voltage DC/DC
module. The ISL8216M is ideal for servers, 48V
telecom/datacom applications, 12V/42V automotive and
industrial equipment, and other distributed power
converters/point-of-load (POL) applications. Only few passive
components and a VOUT setting resistor are needed for a
complete a high voltage power design.
• 10V to 80V (or other voltage rating depending on desired
input voltage for the ISL8216M) power supply with at least
2A source current capability
The ISL8216MEVAL1Z provides an evaluation platform for the
ISL8216M. The input voltage range is from 10V to 80V, and the
output voltage is preset to five options, 5V, 12V, 20V, 24V and
30V. Any other output voltages within the range from 2.5V to
30V can be set with a single resistor.
Quick Start
• Electronic load capable of sinking current up to 4A
• Digital multimeters (DMMs)
• 100MHz quad-trace oscilloscope
1. Select the output voltage by using one of the five jumpers
JP1 to JP5, for 5V, 12V, 20V, 24V or 30V.
2. Connect the VIN (J1) and PGND (J2) terminals to a power
supply and connect the load to the VOUT (J4) and PGND (J3)
terminals.
3. Set the input power supply to desired input voltage between
10V to 80V; note that the input voltage must be higher than
the selected output voltage.
4. Enable the power supply first before turning on the load,
preset the load to 0A.
5. Toggle switch SW1 to the lower position denoted “ENABLE”.
The PGOOD INDICATOR LED should glow in green to indicate
proper operation. Use the digital multimeter to check the
output voltage.
VOUT SELECTION JUMPERS
LOAD
(0A to 4A)
+
+
V VIN
VOUT V
10V to 80V
-
-
FIGURE 1. ISL8216MEVAL1Z BOARD IMAGE
February 10, 2014
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1
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
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Application Note 1907
VIN
ENSS
EX_EN
The ISL8216MEVAL1Z evaluation board has several output voltages
preset for user’s convenience. The 5V, 12V, 20V, 24V, and 30V can
be easily selected by shorting their appropriate jumper. If any other
output voltage between 2.5V and 30V is desired, the user can use a
feedback resistor based on Equation 1.
11.3k
V OUT =  1 + ----------------------------  1.192V


R
(EQ. 1)
FB
NOTE: The output voltage accuracy is not only dependent on the module’s
internal reference voltage, but also on the feedback resistance accuracy.
For higher overall output accuracy, the customer should select a high
accuracy resistor (i.e; 0.5%).
Programming the Switching Frequency
The ISL8216M has an internally set fixed switching frequency of
300kHz. By adding a resistor between VIN and RTCT and a
capacitor between RTCT and SGND, the module’s switching
frequency can be adjusted between 200kHz to 600kHz. The
place holders for the resistor (R5) and capacitor (C5) are provided
on the ISL8216MEVAL1Z evaluation board for the user’s
convenience. Refer to the ISL8216M datasheet for optimum
switching frequency for different conditions.
The SYNC pin can provide the function to synchronize the
ISL8216M’s switching frequency to an external source. When
frequency synchronization is used, the time constant of RT/CT
must be set longer than the period of the sync signal. When the
external sync feature is not used, the customer should tie the
SYNC pin to SGND.
Optional External Enable Control Circuit
The module can be enabled by an external signal by using an
open-drain device, or by adding an external circuit. This optional
ON/OFF
VOUT
Q201
Selecting Output Voltage
R202
Circuits Description
Q202
BIAS VOLTAGE
Q203
R201
The evaluation board size is 76.2mmx76.2mm (3 inchx3 inch).
The FR4 board has four layers, with 2oz copper on the top and
the bottom layers, and 1oz copper on the two internal layers. The
board can be used as 4A reference design. Refer to the
“ISL8216MEVAL1Z Board Schematic” on page 4 and
“ISL8216MEVAL1Z Layouts” on page 5. All the components on
the board, including the solder attachment, are lead free.
external enable circuit is provided on the ISL8216MEVAL1Z
evaluation board, see Figure 2.
D201
Evaluation Board Information
TP14
FIGURE 2. OPTIONAL EXTERNAL ENABLE CIRCUIT
To utilize the circuit shown in Figure 2, the user can place
appropriate components on the place holders for R201, D201,
R202, Q201, and Q202.
A bias voltage of approximately 5.1V is generated from VIN with a
resistor (R201) in series and a zener diode (D201). R202 is a
pull-up resistor of typically 100kΩ, and Q201 and Q202 are
N-MOSFETs. The external control signal is applied to TP14
(EX_EN). When EX_EN is logic low, ENSS is pulled to ground to
disable the module. When EX_EN is logic high, ENSS is released
to allow the module’s soft-start function. The selection of R201 in
series with the zener diode D201 can be calculated as shown in
Equation 2:
V IN – V Z
R201 = ---------------------------IZ
(EQ. 2)
Where:
• VZ is the zener diode D201’s working voltage, nominal 5.1V.
• IZ is the zener diode D201’s working reverse current, typically
about 5mA.
The power dissipation rating should be taken into consideration
when selecting R201.
Other External Circuits Requirements
Depending on the applications conditions, other external circuits
may be required. Table 1 shows these requirements.
TABLE 1. EXTERNAL CIRCUITS REQUIREMENT BASED ON APPLICATION CONDITIONS
CONDITIONS
EXTERNAL CIRCUITS REQUIREMENTS
VOUT
Use PGOOD Signal
Enable Method
PGOOD Delay Circuit
1kΩ Dummy Load Resistor
VIN-BOOT Resistor
≤12V
Yes/No
Self or External Enable Control
No
No
No
>12V
Yes
Self Enable
Yes
Yes
No
>12V
No
Self Enable
No
No
Yes
>12V
Yes
External Enable Control
No
No
Yes
>12V
No
External Enable Control
No
No
Yes
2
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February 10, 2014
Application Note 1907
Optional PGOOD Delay Circuit
The ISL8216M has a PGOOD comparator which monitors the
voltage on the FB pin. The PGOOD is asserted (open drain) when
the FB pin voltage is within 14% of the reference voltage. The
PGOOD is de-asserted under disable, overcurrent protection
event, or over-temperature event.
As described in Table 1, a PGOOD delay circuit, as well as a
dummy load resistor of 1kΩ, 1W rating, are required if all of the
following conditions are met:
• VOUT is higher than 12V
• PGOOD signal is utilized
The place holders for this PGOOD delay circuit (C2, R3 and M1)
and the dummy load resistor (R20) are provided on the
ISL8216MEVAL1Z evaluation board for the user’s convenience,
as shown in Figure 3, where C2 is 1µF, R3 is typically 150kΩ, and
M1 is an N-MOSFET. In the case where input voltage VIN is not
monotonic, an optional Schottky diode is recommended in
parallel with resistor R3, to ensure that the capacitor C2 has
been fully discharged when PVCC starts to rise from 0V.
PGOOD
C2 1µF
M1
2N7002
D1
R3 150k
Output Capacitors
The 6x22µF ceramic capacitors with voltage rating of 35V have
been installed on the ISL8216MEVAL1Z evaluation board.
However, additional place holder to add more capacitors are
provided on the board for evaluating low ESR tantalum capacitor,
low ESR polymer capacitor, and low ESR aluminum electrolytic
capacitor. A minimum total output capacitance of 120µF with
low ESR is recommended.
PCOMPX Pin Configuration
• Module is self enabled/disabled
PVCC
on VOUT capacitors due to leakage from VIN, R23, internal
bootstrap diode, internal bootstrap capacitor, and inductor to
VOUT capacitor.
OPTIONAL
DIODE
Control loop is already compensated internally to provide
sufficient stability margins for applications with various types of
output capacitors. For all ceramic output capacitors, short the
PCOMPX pin to VOUT; a 0Ω resistor R1 is provided on the
evaluation board. For tantalum capacitors, polymer capacitors, or
aluminum electrolytic capacitors, change R1 to resistance of
lower than 1kΩ. The lower the total ESR, the lower the R1 value
should be.
Radiated Emission
The ISL8216M has been evaluated with respect to CISPR 22
radio disturbance limits class B. The radiated emission test was
performed with a simple input filter installed on the
ISL8216MEVAL1Z evaluation board, as shown in Figure 3.
Figure 15 and Figure 16 show the radiated emissions plots with
respect to the CISPR 22 radio disturbance limits class B at
typical operating conditions of 24VIN to 5VOUT at 4A and 24VIN to
12VOUT at 4A.
INPUT FILTER
FIGURE 3. OPTIONAL PGOOD DELAY CIRCUIT WITH DIODE
For VOUT>12V and light load condition, if the optional PGOOD
delay circuit is not used during VIN ramp up, PGOOD logic can
malfunction due to low VOUT as a result of bootstrap capacitor not
being fully charged. This issue can be solved by adding a delay of
about 250ms with this optional delay circuit.
Resistor Between VIN and BOOT
100nH
VIN
ISL8216M
VIN
10µF
2.2µF×4
VDD
FIGURE 4. OPTIONAL INPUT FILTER FOR IMPROVED EMI
PERFORMANCE
As described in Table 1, a resistor between VIN and BOOT is
recommended if ANY of the following conditions are met:
• VOUT is higher than 12V and PGOOD signal is not utilized.
• VOUT is higher than 12V, PGOOD signal is utilized, and module
is enabled/disabled by an external control signal.
The place holder for this resistor, R23, is provided on the
ISL8216MEVAL1Z evaluation board for the user’s convenience.
Refer to the ISL8216M datasheet for the selection of this
resistor. A minimum 0.25W power rating is recommended for
this resistor.
An additional N-MOSFET along with the external enable circuit is
required when R23 is populated. This N-MOSFET is used for
pulling VOUT to ground when the external control signal is logic
low. Without this N-MOSFET, a residual voltage can be generated
3
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ISL8216MEVAL1Z Board Schematic
OPTIONAL EXTERNAL ENABLE CIRCUIT
PGOOD INDICATOR
R30
R201
PVCC
TP10
IN
1
1
IN
2
A14
A12
A11
F8
A8
A7
PAD1
A5
D
B3
E
TP14
A3
C5
PGOOD
C
E
E
RTCT
SYNC
FB
OUT
OPTIONAL PGOOD
DELAY CIRCUIT
FB
C1
PGOOD
OUT
FB
R23
PVIN
IN
IN
C4
DNP
0805
ENSS
E14
ENABLE
2
OUT
ENSS
PAD2
VIN
1
0.1UF
ENSS
PGND
PCOMPX
3
1
SW1
DISABLE
1
1
PCOMPX
IN
1
JP1
JP2
JP3
JP4
JP5
PAD3
PHASE
VOUT
C18
1
PVIN
BLACK
J2
1
IN
E
E
DRAWN BY:
BLACK
J3
PGND
IN
TIM KLEMANN
DATE:
RELEASED BY:
DATE:
DATE:
NET_SHORT
ENGINEER:
07/26/2013
UPDATED BY:
TIM KLEMANN
E
ISL8216M
EVALUATION BOARD
SCHEMATIC
07/31/2013
MASK#
C
REV.
HRDWR ID
ISL8216MEVAL1Z
FILENAME:
~/ISL8216M/ISL8216MEVAL1ZD
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February 10, 2014
FIGURE 5. ISL8216MEVAL1Z BOARD SCHEMATIC
DATE:
TAO TAO
TITLE:
TESTER
E
D
PGND
TP7
DNP
POS_CAP
C112
2
1
DNP
POS_CAP
C111
2
C28
22UF
C27
22UF
C26
22UF
22UF
C25
C24
22UF
22UF
35V
DNP
C23
220UF
50V
1
C21
30V OUT
2
C16
2.2UF
100V
C15
2.2UF
100V
C14
2.2UF
100V
C13
2.2UF
100V
PAD5
PHASE
PAD4
OUT
2
DNP
2512
2
J1
J4
R20
24V OUT
590
RFB5
RED
TP15
E
2
D
GND
TP5
TP6
20V OUT
715
RFB4
OUT
RED
PGND
5V OUT
3.48K
RFB3
2
464
PVIN
D
VOUT
2
TP8
0
0603
VOUT
12V OUT
1.24K
RFB2
D
R1
ALL PARTS ARE (DNP)
RFB1
2
68UF
100V
2
DNP
R3
BOOT
C11
SGND
ISL8216MIRZ-REVC
DNP
1
OPEN
M1
2N7002-7-F
3
C2
IN
U1
PGOOD
F1
PVCC
BOOT
COMP
E1
1
RTCT
FB
D1
OCSET
SHEET
1
OF
D
1
Application Note 1907
B1
VCC
UGATE
SGND
PVCC
A1
PGND
D
PGND
E
ALL PARTS ARE (DNP)
Q1
2N7002-7-F
TP11
3
SYNC
4
C12
10UF
R6
DNP
R5
DNP
0805
OUT
OUT
OPEN
2
TP1
RTCT
DNP
Q203
3
2
2N7002-7-F
DNP
3
1
VOUT
LED1
SSL_LXA3025IGC
PVCC
2
DNP
3
Q202
2
DNP
1
A
NC
E
PVIN
IN
EX_EN
R31
3.32K
E
1
IN
2N7002-7-F
DNP
BZX84C5V1LT1
D201
1
IN
GRN
C
4
2
ENSS
3.32K
RED
3
R202
DNP
Q201
2N7002-7-F
PVIN
IN
3
IN
Application Note 1907
ISL8216MEVAL1Z Layouts
FIGURE 6. TOP SILK SCREEN
FIGURE 7. TOP LAYER COMPONENT SIDE
5
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February 10, 2014
Application Note 1907
ISL8216MEVAL1Z Layouts (Continued)
FIGURE 8. LAYER 2
FIGURE 9. LAYER 3
6
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Application Note 1907
ISL8216MEVAL1Z Layouts (Continued)
FIGURE 10. BOTTOM LAYER SOLDER SIDE
FIGURE 11. BOTTOM SILK SCREEN
7
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February 10, 2014
Bill of Materials
PART NUMBER
H1046-00104-50V10-T
H1065-00106-25V10-T
REF DES
QTY
VALUE
TOL.
VOLTAGE
POWER
PACKAGE TYPE
C4
1
0.1µF
10%
50V
805
MANUFACTURER
Various
C12
1
10µF
10%
25V
1206
Various
C13-C16
4
2.2µF
10%
100V
1210
Various
100ME68AX
C18
2
68µF
20%
100V
THOLE
Sun Electronic
Industries
EEV-FK1H221P
C21
0
DNP
H1082-00225-100V10-T
SMD
6
22µF
C111, C112
0
DNP
108-0740-001
J1-J4
4
69190-202HLF
JP1-JP5
5
THOLE
LED1
1
2N7002-7-F-T
Q1
1
H2511-00R00-1/10W-T
R1
1
0Ω
H2515-DNP
R20
0
DNP
SSL-LXA3025IGC-TR
20%
35V
1206
TDK
SMD
1%
1/10W
Aluminum Electrolytic
Capacitor
Multilayer Ceramic Capacitor
Tantalum Capacitor - Polymer
SMD
Johnson
Components
Banana Jack
BERG/FCI
Jumper
SMD
LUMEX
3mmx2.5mm Surface Mount
LED
SOT-23
Various
N-Channel 60V 115mA
MOSFET
603
Various
Thick Film Chip Resistor
2512
H2511-03321-1/10W1-T
R30, R31
2
3.32kΩ
1%
1/10W
603
Various
Thick Film Chip Resistor
H2511-01241-1/10W1-T
RFB1
1
1.24kΩ
1%
1/10W
603
Various
Thick Film Chip Resistor
H2511-03481-1/10W1-T
RFB2
1
3.48kΩ
1%
1/10W
603
Various
Thick Film Chip Resistor
H2511-07150-1/10W1-T
RFB3
1
715Ω
1%
1/10W
603
Various
Thick Film Chip Resistor
H2511-05900-1/10W1-T
RFB4
1
590Ω
1%
1/10W
603
Various
Thick Film Chip Resistor
H2511-04640-1/10W1-T
RFB5
1
464Ω
1%
1/10W
603
Various
Thick Film Chip Resistor
GT11MCBE
SW1
1
ITT CANNON
SPDT Toggle Switch ROHS
TP1, TP5-TP8, TP10, TP11,
TP14, TP15
9
Keystone
Test Point White
U1
1
Intersil
15mmx15m DC/DC Power
Module
5002
ISL8216MIRZ
THOLE
HDA
Application Note 1907
C23-C28
16TQC68MYF
Multilayer Ceramic Capacitor
Aluminum Electrolytic
Capacitors - SMD
8
C3216X5R1V226M160AC-T
DESCRIPTION
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February 10, 2014
Application Note 1907
Efficiency Performance
100
100
95
24VIN TO 5VOUT 300kHz
95
90
EFFICIENCY (%)
EFFICIENCY (%)
90
85
80
75
48VIN TO 5VOUT 300kHz
70
36VIN TO 5VOUT 300kHz
65
60
75
48VIN TO 12VOUT 400kHz
70
64VINTO 12VOUT 350kHz
65
50
60
1
2
3
4
36VIN TO 12VOUT 400kHz
80
55
0
24VIN TO 12VOUT 400kHz
85
80VIN TO 12VOUT 350kHz
0
1
LOAD CURRENT (A)
FIGURE 12. EFFICIENCY vs LOAD CURRENT (5VOUT AT 300kHz)
2
LOAD CURRENT (A)
4
3
FIGURE 13. EFFICIENCY vs LOAD CURRENT (12VOUT)
100
95
64VIN TO 24VOUT 400kHz
EFFICIENCY (%)
90
48VIN TO 24VOUT 450kHz
85
80
75
80 VIN TO 24VOUT 350kHz
70
65
60
0
1
2
LOAD CURRENT (A)
3
4
FIGURE 14. EFFICIENCY vs LOAD CURRENT (24VOUT)
9
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Application Note 1907
Radiated Emission Performance
CISPR 22 CLASS B
FIGURE 15. RADIATED EMISSION AT 24V IN 5VOUT 4A
CISPR 22 CLASS B
FIGURE 16. RADIATED EMISSION AT 24V IN 12VOUT 4A
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
10
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