CUI VHK75W-Q48-S5

rev.
description
features
The VHK75W series of rugged DC-DC
converters are designed for high
reliability applications, featuring integral
heat sink, over-temperature protection,
over-current protection and input
transient voltage protection. With an
external input fuse, the converter can
protect accidental input polarity reversal.
The wide 4:1 input range (9-36V or 1875V) is very useful to stabilize an input
source like batteries in various
discharging and charging conditions.
Additionally, high efficiency, fast
response, tight regulations, remote sense
and remote On/Off control make these
converters very useful in many industrial
and communications applications.
·50-75W isolated output
·Efficiency to 84%
·RoHS Compliant
·4:1 input range
·Regulated output
·Continuous short circuit
protection
·Metal enclosure with integrated
heatsink
·Rugged design
·Over-temperature shutdown
VHK75W-Q24-S3R3
VHK75W-Q24-S5
VHK75W-Q24-S12
VHK75W-Q24-S15
VHK75W-Q24-S24
VHK75W-Q48-S3R3
VHK75W-Q48-S5
VHK75W-Q48-S12
VHK75W-Q48-S15
VHK75W-Q48-S24
notes:
1 of 9
date
date
08/2009
DESCRIPTION: chassis mount dc-dc converter
PART NUMBER: VHK75W
MODEL
page
page
input voltage
nominal
range
(V dc)
(V dc)
24
24
24
24
24
48
48
48
48
48
output
voltage
(V dc)
9.0~36.0
9.0~36.0
9.0~36.0
9.0~36.0
9.0~36.0
18.0~75.0
18.0~75.0
18.0~75.0
18.0~75.0
18.0~75.0
3.3
5
12
15
24
3.3
5
12
15
24
output
current 1
(A)
15
15
6.25
5
3.12
15
15
6.25
5
3.12
input current
no load
full load
(mA)
(mA)
50
50
50
50
50
50
50
50
50
50
2679
3906
3834
3788
3900
1322
1929
1894
1871
1857
efficiency
typ.
(%)
77
80
81.5
82.5
83
78
81
82.5
83.5
84
1. see output derating curves (page 4)
2. input currents are measured at nominal input voltage
3. efficiency is measured at nominal line, full load
INPUT
parameter
input voltage range
conditions/description
under voltage lockout
24 Vin power up
24 Vin power down
48 Vin power up
48 Vin power down
section 15 in the application notes
PI type
remote on/off control 4
input filter
notes:
min
9
18
nom
24
48
8.8
8
17
16
max
36
75
units
V dc
V dc
V dc
V dc
V dc
V dc
4. add suffix “N” to the model number for negative logic on/off control
*V-Infinity reserves the right to make changes to its products or to discontinue any product or service without notice, and to advise customers to verify the most up-todate product information before placing orders. V-Infinity assumes no liability or responsibility for customer’s applications using V-Infinity products other than repair
or replacing (at V-I’s option) V-Infinity products not meeting V-I’s published specifications. Nothing will be covered outside of standard product warranty.
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2383
www.v-infinity.com
page
2 of 9
date
08/2009
DESCRIPTION: chassis mount dc-dc converter
PART NUMBER: VHK75W
OUTPUT
parameter
voltage accuracy
transient response
external trim adj. range
ripple & noise (20MHz BW)
conditions/description
min
nom
25% step load change
3.3V, 5V
12V& 15V
24V
temperature coefficient
short circuit protection
continuous
line regulation 5
load regulation 6
over voltage protection trip range, % Vo nom.
over current protection
% nominal output current
max
±1
500
±10
40
100
60
150
100
240
units
%
μ sec
%
mV RMS
mV p-p
mV RMS
mV p-p
mV RMS
mV p-p
%/°C
±0.2
±1
140
160
%
%
%
%
max
units
KHz
°C
°C
°C
±0.03
115
110
GENERAL SPECIFICATIONS
parameter
switching frequency
operating ambient temp. 7
storage temperature
thermal shutdown case temp.
case material
conditions/description
min
derated from 50 to 85°C
-40
-55
nom
300
85
105
85
aluminum / steel
ISOLATION SPECIFICATIONS
parameter
isolation voltage
conditions/description
input/output
input/case
output/case
isolation resistance
notes:
5.
6.
7.
min
1500
1500
1500
100
nom
max
units
V dc
V dc
V dc
MΩ
measured from high line to low line at full load
measured from full load to zero load at nominal input
see output derating curves (page 4)
*V-Infinity reserves the right to make changes to its products or to discontinue any product or service without notice, and to advise customers to verify the most up-todate product information before placing orders. V-Infinity assumes no liability or responsibility for customer’s applications using V-Infinity products other than repair
or replacing (at V-I’s option) V-Infinity products not meeting V-I’s published specifications. Nothing will be covered outside of standard product warranty.
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2383
www.v-infinity.com
REV.
A
B
DESCRIPTION
NEW DRAWING
dimension updates
DATE
4/22/2008
8/27/2008
B
107.5 4.232
86.3 3.398
38.0 1.496
15.6 0.614
B
(TYP)
101.76 4.006
91.0 3.583
(2 PLCS)
6 7 8 9
9.70 0.382
(TYP)
18.75 0.738
(2 PLCS) B
70.0 2.756
RoHS
TOLERANCE:
±0.3mm UNLESS OTHERWISE
SPECIFIED
1
B
26.50 1.043
2
3
4
5
9.5 0.374
B
(TYP)
*DIN rail mounting kit available (part# VHK-DIN)
PC FILE NAME:
VHKXXW Series
COPYRIGHT 2008 BY CUI INC.
Material
Aluminum/Steel
Terminal #
Description
1
2
3
4
5
6
7
8
9
- V out
-S
Trim
+S
+ V out
Case
Remote
- V in
+ V in
20050 SW 112th Ave.
Tualatin, OR 97062
Phone: 503-612-2300
800-275-4899
Fax: 503-612-2383
Website: www.cui.com
TITLE:
REV:
VHK
PART NO.
VHKXXW Series
DRAWN BY:
ZRJ
B
UNITS:
MM [INCHES]
APPROVED BY:
SCALE:
1:2
page
4 of 9
date
08/2009
DESCRIPTION: chassis mount dc-dc converter
PART NUMBER: VHK75W
APPLICATION NOTES
1. OUTPUT DE-RATING
The operating ambient temperature range for VHK75W is -40 ~ +85°C, with the actual output power subject to the following de-rating
curves at free-air convection and at forced air conditions. To ensure long-term reliability, it is important to ensure proper cooling at
the worst operating conditions. Please note the derating curves may improve if the converter is mounted on a metal surface to allow
heat conduction.
VHK75W Power Derating Curves @ Nominal Input
120.00%
Natural
Convection
Relative Output Power - % of nominal output
100.00%
0.5 m/S
(100LFM)
1.0 m/S
(200LFM)
80.00%
1.5 m/S
(300LFM)
60.00%
2.0 m/S
(400LFM)
40.00%
2.5 m/S
(500LFM)
3.0 m/S
(600LFM)
20.00%
3.5 m/S
(700LFM)
0.00%
-40
35
40
45
50
55
60
65
70
75
80
85
Ambient Temperature - degrees C
FIGURE 1. OUTPUT DERATING
2. INPUT VOLTAGE RANGE
It is important to ensure the input voltage measured at the converter input pins is within the range for that converter. Make sure wire
losses and voltage ripples are accounted for. One possible problem is driving the converter with a linear unregulated power supply.
For example, if the average voltage measured by a DMM is 9V, with a voltage ripple of 3Vpp, the actual input can swing from 7.5V to
10.5V. This will be outside the specified input range of 9-36V and the converter may not function properly. On the other end, make
sure the actual input voltage does not exceed the highest voltage of 36V or75V.
3. LEAD WIRES
Make sure the input and output wires are of adequate AWG size to minimize voltage drop, and ensure the voltage across the input
terminals is above the converter's rated minimum voltage at all times. It is recommended to have the wire pairs twisted, respectively
for the input pair and the output pair, so as to minimize noise pickup.
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2383
www.v-infinity.com
page
5 of 9
date
08/2009
DESCRIPTION: chassis mount dc-dc converter
PART NUMBER: VHK75W
4. INPUT CURRENT
The input voltage source must be able to provide enough current to the converter, otherwise it may not start up or operate properly. A
typical symptom is not starting or unusually low output voltage. In general, it is recommended to be able to provide at least:
η *Vmin) where Pout is the maximum output power, Vmin is the minimum input voltage and η is the converter's
Ipeak = 150%*Pout/(η
efficiency. As an example, for VHK75W-Q24-S5 to operate with 9~36V input, 75W output and an efficiency of 82%, the minimum
source current is recommended to be: Ipeak = 150% * 75 / (82% * 9) = 15.24A.
5. INPUT FUSE
To limit the input current and to facilitate input reversal protection and input OVP protection, a fast-acting input fuse is recommended
for the input line. The fuse rating will depend on the input range and should allow for the maximum current at the lowest input
η *Vmin).
voltage, as shown in this equation: Ipeak = 150%*Pout/(η
In the previous example of VHK75W-Q24-S5, the peak input current at 9V was calculated to be 15.24A. A 10A or a 15A fuse may be
suitable for this application. Make sure the fuse voltage rating is higher than the maximum input voltage.
6. INPUT OVP
It is important to ensure the input voltage does not exceed the maximum rated input voltage for that model. To suppress voltage
transients of short durations, the converter includes a transient voltage suppression device (TVS) at the input. The built-in TVS has a
rated breakdown voltage of 39V for the VHK75W-Q24-XX models and 82V for the VHK75W-Q48 models. With small transients of
short-durations, the TVS will limit the input voltage without interrupting the converters operations. For large transients, the TVS may
conduct a large amount of current that may trip the input fuse. Without the input fuse, the converter may suffer permanent damages.
When the fuse is open, replace it with one of same type and ratings.
7. INPUT REVERSAL PROTECTION
If the input voltage is reversed for any reason, the built-in protection circuits in the converter will limit the reverse voltage to one diode
drop which is no more than 1V. With an external input fuse connected, the fuse will open and thus remove power from the converter.
Check the wiring and make corrections as needed. The input fuse will need to be replaced. Make sure the new fuse is of the same
type and rating. Without the input fuse, the converter may suffer permanent damages in a reversal situation.
8. REMOTE SENSE
The converter provides regulated outputs at the output terminals. When there is a large current and/or the output cable is of some
length, the voltage at the end of the output cable may be noticeably lower than at the terminals. The converter can compensate up to
0.5V of voltage drop through remote sense terminals. To ensure accurate regulation, run two separate wires (twisted) from the
desired regulation points to the remote sense terminals, as shown below. Even if the load current is low, still connect +Vo to +S and
-Vo to -S.
+Vo
+S
(+)
Load
Trim
(-)
-S
-Vo
FIGURE 2. REMOTE SENSE
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2383
www.v-infinity.com
page
6 of 9
date
08/2009
DESCRIPTION: chassis mount dc-dc converter
PART NUMBER: VHK75W
9. OUTPUT TRIMMING (OPTIONAL)
The output voltages are preset to nominal values as indicated by the models table at the factory. If desired, the output voltage may
optionally be trimmed to a different value (+/- 10%) with external resistors and/or potentiometer as shown below.
+Vo
+Vin
+S
FIGURE 3. TRIMMING WITH
10KΩ
Trimpot
Trim
EXTERNAL POTENTIOMETER
R load
-S
-Vin
-Vo
To trim the output voltage with fixed resistors, the output voltage can be calculated as follows.
Trim-Up
Trim-Down
+Vo
+Vin
+Vo
+Vin
+S
+S
R trim-down
Trim
Trim
R load
R load
R trim-up
-S
-Vin
-S
-Vin
-Vo
-Vo
FIGURE 4: TRIM-UP VOLTAGE SETUP
FIGURE 5: TRIM-DOWN VOLTAGE SETUP
The value of R trim-up is defined as:
The value of R trim-down is defined as:
Rtrim-up =
R1 - R2 x (Vo - Vo, nom)
(KΩ)
Vo - Vo, nom
Rtrim-down =
R1 - R2 x (Vo, nom - Vo)
(KΩ)
Vo, nom - Vo
Where: R trim-up is the external resistor in K Ω . V o,nom is the
Where: R trim-down is the external resistor in K Ω . V o,nom is the
nominal output voltage. V o is the desired output voltage.
nominal output voltage. V o is the desired output voltage.
R 1 and R 2 are internal to the unit and are defined in Table 1.
R 1 and R 2 are internal to the unit and are defined in Table 2.
For example, to trim-up the output voltage of 5.0V module
For example, to trim-down the output voltage of 5.0V module
(VHK75W-Q48-S5) by 8% to 5.4V, R trim-up is calculated
(VHK75W-Q48-S5) by 8% to 4.6V, R trim-down is calculated
as follows:
Vo - Vo, nom = 5.4 - 5.0 = 0.4 V
as follows:
Vo, nom - Vo = 5.0 - 4.6 = 0.4 V
R1 = 5.8 KΩ
R1 = 5.8 KΩ
R2 = 8.2 KΩ
R2 = 10.52 KΩ
Rtrim-up =
Table 1
3.3V
5V
12V
15V
24V
5.8 - 8.2 x 0.4
= 6.3 (KΩ)
0.4
Ω
3.168
5.8
19.656
25.474
42.33
Rtrim-down =
Ω
7.2
8.2
13.304
14.76
16.67
Table 2
5.8 - 10.52 x 0.4
= 3.98 (KΩ)
0.4
3.3V
5V
12V
15V
24V
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2383
Ω
6.18
5.8
86.45
150
430
Ω
15
10.52
60.1
94
120
www.v-infinity.com
page
7 of 9
date
08/2009
DESCRIPTION: chassis mount dc-dc converter
PART NUMBER: VHK75W
10. OUTPUT OCP AND SHORT-CIRCUIT PROTECTION
Output overload and short circuit conditional will cause the output voltage to decline or shutdown altogether.
If the case temperature
is not over 85°C, the output recovers automatically when the short or OCP conditions are removed. In the case of slight overloading,
the output voltage may not shut down, but the converter may build up heat over time, causing over-temperature shutdown.
11. OVER-TEMPERATURE PROTECTION
When the case temperature reaches about 85°C, the converter's built-in protection circuit will shut down the output. When the
temperature is reduced enough to a safe operating level, the converter will recover to normal operations automatically.
12. OUTPUT OVP
In case the output voltage exceeds the OVP threshold, the converter shuts down.
13. OUTPUT PARALLEL CONNECTIONS
The converter is not designed for load share on the output. One may be inclined to use this circuit to force current sharing by
trimming the output voltages for each converter. However, this circuit me not reliably or accurately divide the load current, as the
device characteristics of the converters or the diodes may not be balanced over a range of operating conditions. We generally do not
recommend this circuit to increase power output over a single converter. Instead, we recommend this setup for redundancy only,
having one converter as a backup in case of a failure. Make sure the OR-ing diodes can handle the voltage and full load current.
+Vin
-Vin
FIGURE 6. OUTPUT
+Vo
-Vo
PARALLEL CONNECTIONS
+Vin
-Vin
+Vo
-Vo
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2383
www.v-infinity.com
page
8 of 9
date
08/2009
DESCRIPTION: chassis mount dc-dc converter
PART NUMBER: VHK75W
14. OUTPUT SERIES CONNECTIONS
Two or more converters can be connected in series to obtain a higher output voltage. To prevent output reverse biasing each other in
case of a short, add a Schottky diode on each output in reverse polarity, as shown in the diagram. In the event of a short, the
converters will forward-bias the diodes and the output reversal will be limited to one diode drop (about 0.5V) only, so as not to
damage the converters. The forward current will cause each converter to go into short-circuit protection.
For proper diode selection,
make sure that: 1) the diodes voltage rating is higher than each converter output; 2) the rated diode current can carry the short-circuit
current; 3) the diodes do not overheat before the short is removed.
+Vin
-Vin
FIGURE 7. OUTPUT
+Vo
-Vo
SERIES CONNECTIONS
+Vin
-Vin
+Vo
-Vo
15. REMOTE OUTPUT ON/OFF CONTROL
The converter output can be enabled or disabled through the On/Off pin. The control logic is shown in this table. A common control
circuit is shown below. The standard version defaults to positive logic. For negative logic, indicate the selection when ordering.
REM
+Vo
REM (pin 2)
SW
SW
High signal here
disable output
-Vin
-Vin (pin 4)
-Vo
FIGURE 8. REMOTE ON/OFF CONTROL
FIGURE 9. REMOTE ON/OFF CONTROL
WITH TRANSISTOR SWITCH
Logic Table
Negative logic
SW Closed (V REM <0.8 V) Output on
SW Open (V REM >2.4 V)
Output off
Positive logic
Output off
Output on
16. ISOLATION
The input and output of the converter are electrically isolated. If needed, an output terminal can be connected to an input terminal,
resulting in the converter non-isolated.
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2383
www.v-infinity.com
page
9 of 9
date
08/2009
DESCRIPTION: chassis mount dc-dc converter
PART NUMBER: VHK75W
17. INPUT FILTERING AND EMI INTERFERENCE
The VHK75W converters have input capacitors that control input current ripple and the associated EMI interference. However, it
has not been tested to a formal standard for conducted emissions. Additional filtering may be needed to ensure compliance to an
EMI standard. Refer to FIGURE 10 for a reference circuit.
FIGURE 10. EMI FILTER FOR VHK75W
L2
C2
+Vin
+Vo
-Vin
CASE -Vo
C3
C4
VHK75W Series
C2
47µF/50V
EMI to meet class A
ESR<0.60
220µF/50V
EMI to meet class B
ESR<0.120
C3
47µF/50V
ESR<0.60
220µF/50V
ESR<0.120
C4
2200pF/2KV
L2
2.5µH
2200pF/2KV
1.5µH
note: The recommended components are a starting point but not guaranteed for meeting these EMI requirements. More or less
filtering may be required for a specific application or to meet other EMI standards, e.g.MIL-STD-461
18. OUTPUT FILTERING
The converter has built-in capacitors at the output to control ripple and noise. If desired, additional output capacitance can be
introduced at the input to the powered equipment. Recommended starting point: one 10μF tantalum and one 1μF ceramic capacitor in
parallel at the output.
19. OUTPUT NOISE MEASUREMENT SCHEMATIC
For proper output ripple and noise measurement, connect a 10μF tantalum and a 1μF ceramic capacitor across the output. Set the
scope bandwidth to 20MHz. Probe directly off of one of the capacitors, using a small ground clip to minimize measurement error.
+Vin
+Vo
Ceramic
1.0µF
+S
Trim
+
Resistor
Load
-S
-Vin
-Vo
Solid Tantalum
10µF
To Scope
FIGURE 11. OUTPUT NOISE MEASUREMENT CIRCUIT
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2383
www.v-infinity.com