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date 11/08/2012
page 1 of 6
SERIES: V78-500 │ DESCRIPTION: NON-ISOLATED SWITCHING REGULATOR
date 11/08/2012
page 1 of 6
FEATURES
• 0.5 A current output
• extremely high efficiency up to 97%
• no heat sink required
• pin compatible to LM78XX linear regulators
• available in straight and right angle SIP packages
• low ripple and noise
• short circuit protection, thermal shutdown
• wide temperature (-40~85°C)
RoHS
PART NUMBER KEY
MODEL input
voltage
output
voltage
output
current
output
power
ripple
and noise1
effi ciency
typ
(Vdc)
range
(Vdc) (Vdc)
max
(mA)
max
(W)
max
(mVp-p)
Vin min
(%)
Vin max
(%)
V7801-500 12 4.75~26 1.5 500 0.75 35 76 66
V78X2-500 12 4.75~28 1.8 500 0.9 35 79 67
V7802-500 12 4.75~28 2.5 500 1.25 35 85 73
V7803-500 24 4.75~28 3.3 500 1.65 35 90 80
V7805-500 24 6.5~32 5.0 500 2.5 35 93 84
V78X6-500 24 8~32 6.5 500 3.25 35 94 87
V7809-500 24 11~32 9.0 500 4.5 35 95 91
V7812-500 24 15~32 12 500 6 35 95 92
V7815-500 24 18~32 15 500 7.5 35 96 93
Notes: 1. ripple and noise are measured at 20 MHz BW
V78 XX - 500
Output Voltage Output Current
Base Number
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CUI Inc │ SERIES: V78-500 │ DESCRIPTION: NON-ISOLATED SWITCHING REGULATOR date 11/08/2012 │ page 2 of 6
INPUT
parameter conditions/description min typ max units
operating input voltage
1.5 V output
1.8 V output
2.5 V output
3.3 V output
5 V output
6 V output
9 V output
12 V output
15 V output
4.75
4.75
4.75
4.75
6.5
8
11
15
18
12
12
12
24
24
24
24
24
24
26
28
28
28
32
32
32
32
32
Vdc
Vdc
Vdc
Vdc
Vdc
Vdc
Vdc
Vdc
Vdc
OUTPUT
parameter conditions/description min typ max units
line regulation Vin = min ~ max,
at full load
1.5~2.5 V models
3.3~15 V models
±0.5
±0.2
±1.0
±0.4
%
%
load regulation measured from
10% load to full load
1.5~2.5 V models
3.3~15 V models
±0.4
±0.4
±0.75
±0.6
%
%
voltage accuracy 100% load ±2 ±3 %
switching frequency 100% load, input voltage range 280 330 450 kHz
temperature coeffi cient ±0.02 %/°C
PROTECTIONS
parameter conditions/description min typ max units
short circuit protection continuous, automatic recovery
thermal shutdown internal IC junction 150 °C
SAFETY AND COMPLIANCE
parameter conditions/description min typ max units
MTBF 2,000,000 hours
RoHS compliant yes
ENVIRONMENTAL
parameter conditions/description min typ max units
operating temperature -40 85 °C
storage temperature -55 125 °C
case temperature 100 °C
storage humidity non-condensing 95 %
temperature rise at full load 25 °C
lead temperature 1.5 mm from case for 10 seconds 300 °C
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CUI Inc │ SERIES: V78-500 │ DESCRIPTION: NON-ISOLATED SWITCHING REGULATOR date 11/08/2012 │ page 3 of 6
MECHANICAL
parameter conditions/description min typ max units
dimensions 0.689 x 0.354 x 0.453 (11.50 x 9.00 x 17.50 mm) inch
case material plastic (UL94-V0)
weight 2.0 g
>@
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>@
>@
>@
>@
>@
>@
>@
>@ >@
>@
>@
Front View
Bottom View
Side View
MECHANICAL DRAWING
PIN CONNECTIONS
PIN FUNCTION
1 +Vin
2 GND
3+Vo
units: mm [inches]
tolerance: ±0.25 [±0.010]
pin section tolerance: ±0.10 mm [±0.004]
100
80
60
40
20
Ambient Temperature (°C)
Load (%)
-40 -20 0 20 40 60 71 85 100 120
DERATING CURVES
1. output power vs. ambient temperature
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CUI Inc │ SERIES: V78-500 │ DESCRIPTION: NON-ISOLATED SWITCHING REGULATOR date 11/08/2012 │ page 4 of 6
TYPICAL APPLICATION CIRCUIT
TEST CIRCUIT
+
+Vin
GND
+Vout
0V
DC Power
Source
-
Current
Meter
Voltage
Meter
Cin DC/DC
Converter
Cout
Twisted
30cm, 18AWG
A
B
C01 C02
AAA
BB
B
+
-
+
Current
Meter
Voltage
Meter
Electronic
Load
20MHz
Oscilloscope
1. Cin = 10μF / 50V for 500mA and 22μF / 50V for 1A, Cout = 100μF / 16V.
2. C01 = 10μF / 50V Electrolytic, C02 = 0.1μF / 50V Ceramic.
3. All points labeled A refer to one junction.
4. All points labeled B refer to one junction.
5. Use a short ground loop for probing. Do not use a wired ground clip.
1. C1 and C2 are required and should be fi tted close to the converter pins
2. For the capatance of C1 and C2, see the external capacitor table. Low ESR types should be chosen
3. C3: a low ESR capacitor is required to keep the noise at the converter to a minimum. Ceramic capacitors are preffered, but tantalum of
low ESR electrolytic capacitors may also suffi ce; General use 10F/50V ceramic capacitor. C4 Optional, General use 100F/25V
electrolytic capacitor.
4. No parallel connection or plug and play
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CUI Inc │ SERIES: V78-500 │ DESCRIPTION: NON-ISOLATED SWITCHING REGULATOR date 11/08/2012 │ page 5 of 6
50
55
60
65
70
75
80
85
90
95
100
10 20 30 32
Vin(V) 0
10
20
30
40
50
10 20 30 32
Vin(V)
60
65
70
75
80
85
90
95
100
100 200 300 400 500 600
0
10
20
30
40
50
100 200 300 400 500 600
20
30
40
50
60
70
80
90
100
100 200 300 400 500 600
0
10
20
30
40
50
100 200 300 400 500 600
V7803-500
V7805-500
V7806-500
V7809-500
V7812-500
V7815-500
V7803-500
V7805-500
V7806-500
V7809-500
V7812-500
V7815-500
V7803-500
V7805-500
V7806-500
V7809-500
V7812-500
V7815-500
V7803-500
V7805-500
V7806-500
V7809-500
V7812-500
V7815-500
Efficiency Output
Ripple
Efficiency (%)
Efficiency (%)
Efficiency vs. Load (Vin=Vin_min)
Output Current(mA)
Efficiency vs. Load (Vin=Vin_max)
Output Current (mA)
Efficiency (%)
Ripple vs. Vin ( Full Load)
Ripple (mVpp)
Ripple vs. Load (Vin=Vin_min)
Output Current (mA)
Ripple (mVpp)
Efficiency vs. Vin (Full Load)
Ripple vs. Load (Vin=24V)
Output Current (mA)
Ripple (mVpp)
V7803-500
V7805-500
V7806-500
V7809-500
V7812-500
V7815-500
V7803-500
V7805-500
V7806-500
V7809-500
V7812-500
V7815-500
EFFICIENCY AND RIPPLE
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CUI Inc │ SERIES: V78-500 │ DESCRIPTION: NON-ISOLATED SWITCHING REGULATOR date 11/08/2012 │ page 6 of 6
CUI offers 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
affect its safety or effectiveness.
Headquarters
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 07/13/2010
1.01 new template applied 04/18/2012
1.02 V-Infi nity branding removed 09/04/2012
1.03 updated typical application circuits 09/25/2012
1.04 updated external capacitor values 11/08/2012
The revision history provided is for informational purposes only and is believed to be accurate.
REVISION HISTORY
EXTERNAL CAPACITOR TABLE
Part C1,C3 C2,C4
Number (Ceramic Capacitor) (Ceramic Capacitor)
V7801-500 10 F/50V 22 F/6.3V
V78X2-500 10 F/50V 22 F/6.3V
V7802-500 10 F/50V 22 F/6.3V
V7803-500 10 F/50V 22 F/6.3V
V7805-500 10 F/50V 22 F/10V
V78X6-500 10 F/50V 10 F/10V
V7809-500 10 F/50V 10 F/16V
V7812-500 10 F/50V 10 F/25V
V7815-500 10 F/50V 10 F/25V
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