www.recom-power.com REV.: 4/2018 I-1
Features
Switching
Regulator
• Efficiency up to 95%, no need for heatsinks
• High reflow temperature SMD package
• Adjustable output voltage
• Wide input range (4.74V - 32V)
• Short circuit protection, thermal shutdown
• Remote on/off control
• very low shutdown current
R-78AA-0.5
Description
The R-78AAxx-0.5SMD series are manufactured without lead and meet the requirements for
RoHS 10/10 as well as the increased reflow soldering temperatures associated with va-
por phase soldering, making these high efficiency switching regulators ideally suited to modern
pick-and-place mass production. The efficiency of up to 97% means that very little energy
is wasted as heat. The additional features of remote on/off control and adjustable output
voltages will find many uses in the battery-powered, industrial, medical and automotive markets.
DC/DC Converter
0.5 Amp
SMD
Single Output
EN60950-1 certified
IEC60950-1 certified
Selection Guide
Part Input Output Vout Output Efficiency
Number Voltage Range Voltage Adjust Range Current @ min Vin @ max. Vin
[VDC] [VDC] [VDC] [mA] [%] [%]
R-78AA1.5-0.5SMD 4.75 - 30 1.5 fixed 0.5 73 63
R-78AA1.8-0.5SMD 4.75 - 32 1.8 1.5 - 3.0 0.5 82 71
R-78AA2.5-0.5SMD 4.75 - 32 2.5 1.5 - 3.0 0.5 87 77
R-78AA3.3-0.5SMD 4.75 - 32 3.3 3.0 - 5.5 0.5 91 81
R-78AA5.0-0.5SMD 6.5 - 32 5.0 3.0 - 8.0 0.5 94 86
R-78AA6.5-0.5SMD 8.0 - 32 6.5 3.3 - 11.0 0.5 95 88
R-78AA9.0-0.5SMD 11 - 32 9.0 4.5 - 12.6 0.5 96 92
R-78AA12-0.5SMD 15 - 32 12 4.5 - 12.6 0.5 97 94
R-78AA15-0.5SMD 18 - 32 15 fixed 0.5 97 95
Model Numbering
Notes:
Note2: add suffix -R for tape & reel packaging
Notes:
Note1: 1.5VDC Output can be unstable with Vin>30VDC
Ordering Examples:
R-78AA5.0-0.5SMD-R = 5.0VDC Output Volage, 0.5A, SMD, tape and reel packaging
R-78AA2.5-0.5SMD = 2.5VDC Output Volage, 0.5A, SMD, tube
nom. Output Voltage
Output Current
Packaging (2)
Package
R-78AA__-0.5 SMD-_
www.recom-power.com REV.: 4/2018 I-2
DC/DC Converter
Specifications (measured @ Ta= 25°C, 10% minimum load, unless otherwise stated)
R-78AA-0.5
Series
BASIC CHARACTERISTICS
Parameter Condition Min. Typ. Max.
Absolut Maximum Input Voltage 34VDC
Quiescent Current Vin= min. to max. 5mA 7mA
Internal Power Dissipation 0.4W
Trimming see calculation
Minimum Load (3) 0%
Start-up time ON/OFF CTRL 50ms
ON/OFF CTRL DC-DC ON
DC-DC OFF
Open or 2.8VDC<Vr<5VDC
GND or 0VDC<Vr<0.8VDC
Input Current of CTRL Pin DC-DC OFF 1.8µA
Standby Current 20µA 30µA
CTRL thereshold voltage 2.4VDC 2.6VDC 2.8VDC
CTRL voltage hysterese 250mV
Internal Operating Frequency 280kHz 330kHz 380kHz
Output Ripple and Noise 20MHz BW 1.5VDC tp 6.5VDC
9VDC to 15VDC
20mVp-p
30mVp-p
30mVp-p
40mVp-p
Maximum Capacitive Load with normal start-up time, no external components 470µF
with <1 second start-up time + diode protection circuit 6800µF
continued on next page
Notes:
Note3: Operation under no load will not harm the converter, but specifications may not be met.
A minimum load of 6mA is recommended
+Vin +Vout
R1
R2 R3
Rdown
Rup
GND
Vref
GND
Vadj
Controlled IC
Adjustment Resistor Values
Trimming
V0 R1 R2 R3 Vref(V)
1.8V 10kΩ 21kΩ 5.6kΩ 1.23
2.5V 22kΩ 21kΩ 5.6kΩ 1.23
3.3V 16.9kΩ 10kΩ 5.6kΩ 1.23
5.0V 30.9kΩ 10kΩ 10kΩ 1.23
6.5V 43kΩ 10kΩ 10kΩ 1.23
9V 63.4kΩ 10kΩ 22.1kΩ 1.23
12V 88.7kΩ 10kΩ 22.1kΩ 1.23
Rdown = R2(R1 + R3) x (Vref - Vo) + Vref x R1R3
R2Vo - Vref (R1 + R2)
Rup = R2R3 (Vref - Vo) + Vref R1 (R2 + R3)
R2 (Vo - Vref) - Vref R1
www.recom-power.com REV.: 4/2018 I-3
DC/DC Converter
Specifications (measured @ Ta= 25°C, 10% minimum load, unless otherwise stated)
R-78AA-0.5
Series
0 10 20 30 40 50 60 70 80 90 100
100
80
60
40
90
70
50
30
20
10
0
Efficiency [%]
Output Load [%]
15Vout
12Vout
5Vout
3.3Vout
1.8Vout
1.5Vout
0 10 20 30 40 50 60 70 80 90
100
25
20
15
10
5
0
Ripple [mV]
Output Load [%]
15Vout
12Vout
5Vout
3.3, 9Vout
1.8Vout
1.5Vout
100 20 30 40 50 60 70 80 90
100
40
30
20
50
45
35
25
15
10
5
0
Ripple [mV]
Output Load [%]
15Vout
12Vout
9Vout
5Vout
3.3Vout
1.8Vout
1.5Vout
0 10 20 30 40 50 60 70 80 90 100
100
80
60
40
90
70
50
30
20
10
0
Efficiency [%]
Output Load [%]
15,12Vout
5Vout
3.3Vout
1.8Vout
1.5Vout
Efficiency vs. Load (max. Vin)
Efficiency vs. Load (min. Vin)
Ripple vs. Load (max. Vin)
Ripple vs. Load (min. Vin)
4.75 10 15 20 25 30 34
100
80
60
40
90
70
50
30
20
10
0
Efficiency [%]
Input Voltage [VDC]
15, 12Vout
9Vout
5Vout
3.3Vout
1.8Vout
1.5Vout
4.75 10 15 20 25 30 34
50
40
30
20
55
45
25
15
10
5
0
Efficiency [%]
Input Voltage [VDC]
15Vout
12Vout
9Vout
5Vout
3.3Vout
1.8Vout
1.5Vout
Efficiency vs. Vin (full load) Ripple vs. Vin (full load)
www.recom-power.com REV.: 4/2018 I-4
DC/DC Converter
Specifications (measured @ Ta= 25°C, 10% minimum load, unless otherwise stated)
R-78AA-0.5
Series
PROTECTIONS
Parameter Condition Value
Short Circuit Protection (SCP) continuous, automatic recovery
Short Circuit Input Current nom. Vin= 24VDC 60mA typ. / 100mA max.
Optional Diode Protection Circuit
+Vin +Vout
+Vout
Trim output voltage
up 1 diode drop
GNDGND
R-78AAxx
-0.5SMD
R-78AAxx
-0.5SMD
CTRL
+Vin +Vout
GND Vadj
CTRL
+Vin +Vout
GNDCTRL
CTRL
+Vin
GNDGND
+Vin +Vout
+Vout
Trim output voltage
up 1 diode drop
GNDGND
R-78AAxx
-0.5SMD
R-78AAxx
-0.5SMD
CTRL
+Vin +Vout
GND Vadj
CTRL
+Vin +Vout
GNDCTRL
CTRL
+Vin
GNDGND
Add a blocking diode to Vout if
current can flow backwards into
the output, as this can damage the
converter when it is powered down.
The diode can either be fitted
across the device if the source is
low impedance or fitted in series
with the output (recommended).
Optional Protection 1: Optional Protection 2:
ENVIRONMENTAL
Parameter Condition
Value
Operating Temperature Range with derating (see graph) -40°C to +85°C
Maximum Case Temperature +100°C
Temperature Coefficient ±0.015%/°C
Thermal Impedance 0.1m/s, horizontal 70°C/W
Operating Altitude 2000m
Operating Humidity non-condensing 5% - 95% RH max.
Pollution Degree PD2
MTBF according to MIL-HDBK-217F, G.B. +25°C
+ 71°C
21098 - 29253 x 103 hours
4214 - 7365 x 103 hours
Derating Graph
-40 -20 0 20 40 70
71 85
60-30 -10 10 30 50 80 90 100
100
80
60
40
90
70
50
30
20
10
0
Output Load [%]
Ambient Temperature [°C]
REGULATIONS
Parameter Condition Value
Output Accuracy full load ±2.0% typ. / ±3.0% max.
Line Regulation low line to high line
at full load
1.5 VDC tp 6.5VDC
9VDC to 15VDC
±0.2% typ. / ±0.4% max.
±0.1% typ. / ±0.2% max.
Load Regulation 10% to 100% load 1.5 VDC tp 6.5VDC
9VDC to 15VDC
±0.7% typ. / ±1.0% max.
±0.25% typ. / ±0.4% max.
Transient Response with a 100µF output
capacitor
100% <-> 50% load
100% <-> 10% load
±85mV typ. / ±100mV max.
±100mV typ.
www.recom-power.com REV.: 4/2018 I-5
DC/DC Converter
Specifications (measured @ Ta= 25°C, 10% minimum load, unless otherwise stated)
R-78AA-0.5
Series
SAFETY AND CERTIFICATIONS
Certificate Type (Safety) Report / File Number Standard
Information Technology Equipment, General Requirements for Safety
1603123 IEC60950-1:2005, 2nd Edition + AM 2:2013
EN60950-1:2006 + AM 2:2013
EAC RU-AT.49.09571 TP TC 004/2011
RoHS 2+ RoHS 2011/65/EU + AM2015/863
EMC Compliance Condition Standard / Criterion
Electromagnetic compatibility of multimedia equipment -
Emission requirements with external filter EN55032, Class A and B
ESD Electrostatic discharge immunity test Air ±8kV; Contact ±4kV EN61000-4-2
Radiated, radio-frequency, electromagnetic field immunity test 3V/m EN61000-4-3
EMC Filtering Suggestions according to EN55032
C1
L1
R-78AA-0.5SMD
C2
+V
out
-V
in
-V
in
+V
in
+Vin +Vout
GND
Component List Class A
Component List Class B
MODEL C1 C2 L1
R78AA5.0-0.5SMD 10µF MLCC 100V - 3.9µH
MODEL C1 C2 L1
R78AA5.0-0.5SMD 10µF MLCC 100V 10µF MLCC 100V 5.6µH
DIMENSION AND PHYSICAL CHARACTERISTICS
Parameter Type Value
Material case
PCB
non-conductive black plastic, (UL94 V-2)
FR4, (UL94 V-1)
Dimension (LxWxH) 15.3 x 9.6 x 8.8mm
Weight 2.7g typ.
continued on next page
www.recom-power.com REV.: 4/2018 I-6
DC/DC Converter
Specifications (measured @ Ta= 25°C, 10% minimum load, unless otherwise stated)
R-78AA-0.5
Series
INSTALLATION AND APPLICATION
continued on next page
10 9 8 7 6
10 9 8 7 6
12345
12345
Bottom View Top View
0.50±0.05
15.3
15.0
2.54 x 4
9.4
9.68.812.35
9.24
13.00
1.30 1.202.54
1.80
10 9 8 7 6
10 9 8 7 6
12345
12345
Bottom View
Top View
0.50±0.05
15.3
15.0
2.54 x 4
9.4
9.68.812.35
9.24
13.00
1.30
1.20
2.54
1.80
Dimension Drawing (mm)
Recommended Footprint Details
Pinning information
Pin # Single
1,2 +Vin
3,7,8,9 GND
4,5 +Vout
6 Vadj
10 CTRL
Tolerance:
xx.x= 0.5mm
xx.xx= ±0.25mm
+Vin +Vout
Rdown
Rup
GNDGND
To protect the converter from high inrush currents, use soft start Vin and C1 = 10µF
Output capacitor C2 recommended if load is very dynamic
CTRL
R-78AAxx-0.5SMD
C1
100µF
(optional)
10µF
(optional)
C2
+Vin +Vout
GND Vadj
CTRL
Standard Application Circuit
Pin Connections
Pin # Negative Positive
1,2 +Vin +Vin
3,7,8,9 -Vout GND
4,5 GND +Vout
6 -Vadj +Vadj
10 CTRL CTRL
Positive to Negative Converter
C1 and C2 are required and should
be fitted close to the converter pins.
Maximum capacitiv load including
C2 is 220µF
+Vin
GND
-Vout
Rdown
Rup
GND
On/Off
(reference to -Vout)
R-78AAxx-0.5SMD
C1
C2
+Vin
-Vout
GND
-Vadj
CTRL
www.recom-power.com REV.: 4/2018 I-7
DC/DC Converter
Specifications (measured @ Ta= 25°C, 10% minimum load, unless otherwise stated)
R-78AA-0.5
Series
+Vin
Rdown
Rup
On/Off
R-78AAxx-0.5SMD
GND Octo-
coupler
-Vout
Rdown
Rup
GND
Maximum capacitive
load ±220µF
+Vout
R-78AAxx-0.5SMD
C1
C2
Octo-
coupler
+Vin +Vout
GND Vadj
CTRL
+Vin
-Vout
GND
-Vadj
CTRL
Dual Output (two Converters) with Negative Output
Selection Guide - Negative Output
Notes:
Note6: Maximum Capacitive Load including C2 is 220µF
Part Input Output Output Efficiency External Capacitor
Number Voltage Range Voltage Current @ min Vin @ max. Vin C1 C2 (6)
[VDC] [VDC] [A] [%] [%]
R-78AA1.5-0.5SMD 4.75 - 28 -1.5 -0.4 68 67 10µF/35V 22µF/6.3V
R-78AA1.8-0.5SMD 4.75 - 28 -1.8 -0.4 71 70 10µF/50V 22µF/6.3V
R-78AA2.5-0.5SMD 4.75 - 28 -2.5 -0.4 75 76 10µF/50V 22µF/6.3V
R-78AA3.3-0.5SMD 4.75 - 28 -3.3 -0.4 77 80 10µF/50V 22µF/6.3V
R-78AA5.0-0.5SMD 4.75 - 28 -5.0 -0.4 79 84 10µF/50V 22µF/10V
R-78AA6.5-0.5SMD 5.0 - 26 -6.5 -0.3 81 86 10µF/50V 10µF/10V
R-78AA9.0-0.5SMD 8.0 - 18 -9.0 -0.2 87 89 10µF/50V 10µF/16V
R-78AA12-0.5SMD 8.0 - 18 -12 -0.2 87 90 10µF/50V 10µF/25V
R-78AA15-0.5SMD 8.0 - 18 -15 -0.2 87 91 10µF/50V 10µF/25V
+
-
26k +5V
100k +7.5V
200k +9V
+12V
R-78AA12-0.5SMD
-Vout
GND
+Vout
R-78AAxx-0.5SMD
10µF
22µF
26k -5V
100k -7.5V
200k -9V
-12V
+Vin +Vout
GND Vadj
CTRL
+Vin
-Vout
GND
-Vadj
CTRL
Dual Rail Selectable Output Voltage Power Supply
www.recom-power.com REV.: 4/2018 I-8
DC/DC Converter
Specifications (measured @ Ta= 25°C, 10% minimum load, unless otherwise stated)
R-78AA-0.5
Series
+Vin +Vout
GND
6800µF
GND
R-78AAxx
-0.5SMD
+Vin +Vout
GND
3.3V/5V Selectable 1A Power Supply
Application Examples
Flash Memory Program Voltage Switcher
C2
C1
+Vin
GND
GND
DC/DC Converter (1:1)
+Vout
R-78AA-0.5SMD
- High Isolation Voltage
- Improved Loading / Line Regulation
- Wide Input Voltage
- Point-of-Load Architecture
- CTRL On/Off Control
„Program“ = 0V, PGM Pin = +5V
„Program“ = high, PGM Pin = +12.6V
C1, C2: optional
CTRL
C1
220kΩ
24kΩ
R-78AA-0.5SMD
Reprogrammable
Flash Memory
+Vin
0V 0V
Program
PGM
+Vin +Vout
GND
+Vin +Vout
GND
Vadj
CTRL
PACKAGING INFORMATION
Parameter Type Value
Packaging Dimension (LxWxH) tube
tape and reel (carton)
530.0 x 17.0 x 13.0mm
355.0 x 342.0 x 36.0mm
Packaging Quantity tube
tape and reel
33pcs
250pcs
Tape Width 24mm
Storage Temperature Range -55°C to +125°C
Storage Humidity 95% RH max.
The product information and specifications may be subject to changes even without prior written notice.The product has been designed for various applications; its suitability lies in the responsibility of each customer.
The
products are not authorized for use in safety-critical applications without RECOM’s explicit written consent. A safety-critical application is an application where a failure may reasonably be expected to endanger or
cause
loss of life, inflict bodily harm or damage property. The applicant shall indemnify and hold harmless RECOM, its affiliated companies and its representatives against any damage claims in connection with the
unauthorized
use of RECOM products in such safety-critical applications.
