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date 01/22/2020
page 1 of 7
SERIES: VX78-500-W │ DESCRIPTION: NON-ISOLATED DC SWITCHING REGULATOR
FEATURES
• low Profile
• pin-out compatible with linear regulators
• high efficiency up to 95%
• no-load input current as low as 0.2 mA
• wide temperature range: -40°C ~ +85°C
• support negative output
• output short circuit protection
MODEL input
voltage1
output
voltage
output
current
output
power
ripple
& noise2
eciency3
typ
(Vdc)
range
(Vdc) (Vdc)
max
(mA)
max
(W)
max
(mVp-p)
typ
(%)
VX7803-500-W 24 4.75~36 3.3 500 1.65 75 86
VX7805-500-W 24
12
6.5~36
7~31
5
-5
500
-300
2.5
1.5
75
75
90
80
VX7809-500-W 24 12~36 9 500 4.5 75 93
VX7812-500-W 24
12
15~36
8~24
12
-12
500
-150
6
1.8
75
75
94
84
VX7815-500-W 24
12
19~36
8~21
15
-15
500
-150
7.5
2.25
75
75
95
85
Notes: 1. For input voltages higher than 30 Vdc, a 22 µF / 50 V input capacitor is required.
2. Tested at nominal input, 10~100% load, 20 MHz bandwidth, with 10 µF electrolytic and 1 µF ceramic capacitor on the output. At loads below 10%, the max ripple and
noise of the 3.3 & 5 Vdc outputs will be 150 mVp-p, and the other outputs will be 2% Vo.
3. Measured at min Vin, full load.
4. All specications are measured at Ta=25°C, humidity < 75%, nominal input voltage, and rated output load unless otherwise specied.
PART NUMBER KEY
Base Number
VX78 XX - 500 - W
Output Voltage Output Current
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date 01/22/2020 │ page 2 of 7CUI Inc │ SERIES: VX78-500-W │ DESCRIPTION: NON-ISOLATED DC SWITCHING REGULATOR
INPUT
parameter conditions/description min typ max units
operating input voltage see Model section on page 1 for specic
input voltage ranges
lter capacitor lter
input reverse polartiy protection no
no-load input current positive outputs 0.2 1.5 mA
OUTPUT
parameter conditions/description min typ max units
maximum capacitive load2for positive output applications
for negative output applications
680
330
μF
μF
voltage accuracy
at full load, input voltage range
3.3 Vdc output model
all other models
±2
±2
±4
±3
%
%
line regulation at full load, input voltage range ±0.2 ±0.4 %
load regulation at nominal input, 10~100% load ±0.4 ±1.5 %
switching frequency at nominal input voltage, full load 550 850 kHz
transient recovery time at nominal input voltage, 25% load step change 0.2 1 ms
transient response deviation at nominal input voltage, 25% load step change 50 250 mV
temperature coecient at full load ±0.03 %/°C
Note: 2. The maximum capacitive load was tested at nominal input voltage, full load.
PROTECTIONS
parameter conditions/description min typ max units
short circuit protection continuous, auto recovery
SAFETY AND COMPLIANCE
parameter conditions/description min typ max units
safety approvals EN62368-1
conducted emissions CISPR32/EN55032, class B (see Figure 5-➁ for recommended circuit)
radiated emissions CISPR32/EN55032, class B (see Figure 5-➁ for recommended circuit)
ESD IEC/EN61000-4-2, contact ± 4kV, perf. Criteria B
radiated immunity IEC/EN61000-4-3, 10V/m, perf. Criteria A
EFT/burst IEC/EN61000-4-4, ± 1kV, perf. Criteria B (see Figure 5-① for recommended circuit)
surge IEC/EN61000-4-5, line-line ± 1kV, perf. Criteria B (see Figure 5- ① for recommended circuit)
conducted immunity IEC/EN61000-4-6, 3 Vr.m.s, perf. Criteria A
MTBF as per MIL-HDBK-217F, 25°C 2,000,000 hours
RoHS 2011/65/EU
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date 01/22/2020 │ page 3 of 7CUI Inc │ SERIES: VX78-500-W │ DESCRIPTION: NON-ISOLATED DC SWITCHING REGULATOR
ENVIRONMENTAL
parameter conditions/description min typ max units
operating temperature -40 85 °C
storage temperature -55 125 °C
storage humidity non-condensing 5 95 %
SOLDERABILITY
parameter conditions/description min typ max units
hand soldering welding time: 10s (Max.) 260 °C
MECHANICAL
parameter conditions/description min typ max units
dimensions 11.50 x 9.00 x 17.50 [0.453 x 0.354 x 0.689 inch] mm
case material black ame-retardant heat-proof plastic (UL94V-0)
weight 5 g
MECHANICAL DRAWING
units: mm [inch]
tolerance: ±0.50[±0.020]
wire type: UL1569 AWG22 (300V 105°C)
PIN CONNECTIONS
PIN +OUTPUT -OUTPUT
1 (red) Vin Vin
2 (black) GND -Vo
3 (yellow) +Vo GND
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date 01/22/2020 │ page 4 of 7CUI Inc │ SERIES: VX78-500-W │ DESCRIPTION: NON-ISOLATED DC SWITCHING REGULATOR
DERATING CURVE
Safe Operating Area
Operating Temperature (°C)
Temperature Derating Curve
-40 0407185 120
0
20
40
60
80
100
120
Output Power (%)
EFFICIENCY CURVES
VX7805-500-W Eciency Curve
Eciency vs. Input Voltage
(at full load)
VX7805-500-W Eciency Curve
Eciency vs. Output Load
(Vin = 24V)
VX7815-500-W Eciency Curve
Eciency vs. Input Voltage
(at full load)
VX7815-500-W Eciency Curve
Eciency vs. Output Load
(Vin = 24V)
Figure 1
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date 01/22/2020 │ page 5 of 7CUI Inc │ SERIES: VX78-500-W │ DESCRIPTION: NON-ISOLATED DC SWITCHING REGULATOR
Table 1
External Capacitor Table
Model Number C1, C3
(ceramic capacitor)
C2, C4
(ceramic capacitor)
VX7803-500-W 10 μF/50 V 22 μF/10 V
VX7805-500-W 10 μF/50 V 22 μF/10 V
VX7809-500-W 10 μF/50 V 22 μF/16 V
VX7812-500-W 10 μF/50 V 22 μF/25 V
VX7815-500-W 10 μF/50 V 22 μF/25 V
TYPICAL APPLICATION CIRCUIT
Positive Output Application Circuit Negative Output Application Circuit
Positive and Negative Output Paralleling Application Circuit
Figure 3
Figure 2
Positive Output Ripple Reduction Circuit Negative Output Ripple Reduction Circuit
Figure 4
+V
in
GNDGND
DC /DC
1
2
3+Vou
t
C1
+Vin
GN DGN D
DC/DC
12
3
-Vout
C1
C2
1
3
2
+V
in
GND
-Vout
C2
GND
DC/DC
1
2
3+Vout
C1
C3 C4
LDM
DC/DC
3
+V
in
GND
Vout
1
DC/DC
C1
22 F
μ
2
C2
L
2
+Vin
GND
Vout
1
DC/DC
C1
22 F
μ
3
C2
L
Note: 1.C1 and C2 (C3 and C4) are required and should be connected close to the pin terminal of the module.
2.The capacitance of C1 and C2 (C3 and C4) refer to Sheet 1, it can be increased properly if required, and tantalum or low ESR electrolytic capacitors may also suce.
3.When the products used as the circuit like gure 3, an inductor named as LDM up to 10μH is recommended in the circuit to reduce the mutual interference.
4.Cannot be used in parallel for output and hot swap.
To reduce the output ripple furtherly, it is suggested to connect a “LC” lter at the output terminal, and recommended value of L is 10µH-47µH.
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date 01/22/2020 │ page 6 of 7CUI Inc │ SERIES: VX78-500-W │ DESCRIPTION: NON-ISOLATED DC SWITCHING REGULATOR
EMC RECOMMENDED CIRCUIT
DC /DC
Vin
LD M2
ĸ
C0
LD M1
MOV
FUSE
ķ
C5
V
in
GN
D
+
+Vo
GND
LO AD
C2C1
Table 2
Recommended external circuit components
FUSE choose according to actual input current
MOV S20K30
LDM1 82 µH
C0 680 µF/50 V
C1, C2 see Table 1
C5 4.7 µF/50 V
LDM2 12 µH
Note: 1. Part ① in Fig. 5 is for EMS test, part ➁ is for EMI ltering; parts ① and ➁ can be added based on actual requirement.
Figure 5
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date 01/22/2020 │ page 7 of 7CUI Inc │ SERIES: VX78-500-W │ DESCRIPTION: NON-ISOLATED DC SWITCHING REGULATOR
CUI oers a two (2) year limited warranty. Complete warranty information is listed on our website.
CUI reserves the right to make changes to the product at any time without notice. Information provided by CUI is believed to be accurate and reliable. However, no responsibility is
assumed by CUI for its use, nor for any infringements of patents or other rights of third parties which may result from its use.
CUI products are not authorized or warranted for use as critical components in equipment that requires an extremely high level of reliability. A critical component is any component of a
life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to aect its safety or eectiveness.
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20050 SW 112th Ave.
Tualatin, OR 97062
800.275.4899
Fax 503.612.2383
cui.com
techsupport@cui.com
rev. description date
1.0 initial release 01/22/2020
The revision history provided is for informational purposes only and is believed to be accurate.
REVISION HISTORY
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