Industrial Environment Switching Regulators, PCB & Chassis PSR Series
Edition 4/4.99
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MELCHER
The Power Partners.
PSR: Positive Switching Regulators PSR-Series
No input to output isolation
Single output of 5, 12, 15, 24 or 36 V DC/15...72 W
Input voltage up to 80 V DC
•High efficiency up to 94%
•Wide input voltage range
• Low input to output differential voltage
•Very good dynamic properties
•Input undervoltage lock-out
•Parallel configurations possible
•Continuous no-load and short-circuit proof
•No derating
Table of Contents Page
Summary.......................................................................... 1
Type Survey and Key Data.............................................. 1
Type Key .......................................................................... 2
Functional Description ..................................................... 2
Electrical Input Data ........................................................ 3
Electrical Output Data...................................................... 4
Auxiliary Functions .......................................................... 5
Page
Electromagnetic Compatibility (EMC) ............................. 6
Immunity to Environmental Conditions ........................... 7
Mechanical Data .............................................................. 8
Safety and Installation Instructions ................................. 8
Description of Options ................................................... 10
Accessories ................................................................... 11
Summary
The PSR series of positive switching regulators is de-
signed as power supply modules for electronic systems.
Their major advantages include a high level of efficiency
that remains virtually constant over the entire input range,
high reliability, low ripple and excellent dynamic response.
Safety according to IEC/EN 60950
C
Modules with input voltages up to 80 V are specially de-
signed for secondary switched and battery driven applica-
tions. The case design allows operation at nominal load up
to 71°C without additional cooling.
Non standard input/output configurations or special custom adaptions are available on request.
See also:
Commercial Information: Inquiry Form for Customized Power Supply.
70
2.8"
50
2.0"
25
1.0"
Type Survey and Key Data
Table 1: Type survey
Output Output Input Input Efficiency 2 Type Options
voltage current voltage range voltage designation
U
o nom [V]
I
o nom [A]
U
i [V] 1
U
i nom [V]
η
min [%]
η
typ [%]
5 5 7...35 20 81 83 PSA 55-7 -9, i, P, R, Y
5 4 7...40 20 82 83 PSR 54-7 -9, i, P, R, Y
5 3 8...80 40 77 79 PSR 53-7 -9, i, P, R, Y
5 2 8...80 40 72 74 PSR 52-7 Y
12 2.5 15...80 40 86 87 PSR 122.5-7 -9, i, P, R, Y
15 2.5 19...80 40 88 89 PSR 152.5-7 -9, i, P, R, Y
24 2 29...80 50 91 92 PSR 242-7 -9, i, P, R, Y
36 2 42...80 60 92 94 PSR 362-7 -9, i, P, R, Y
1See also:
Electrical Input Data:
D
U
io min
.
2Efficiency at
U
i nom and
I
o nom.
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Type Key
PSR 12 2.5 -7 i R P Y
Positive switching regulator in case A01 ..................... PSR
Nominal output voltage in volt ................................... 5...36
Nominal output current in ampere ............................... 2...5
Operational ambient temperature range
T
A
–25...71°C ........................................................... -7
–40...71°C (option) .............................................. -9
Options:
Inhibit input ............................................................ i
Control input for output voltage adjustment 1 ....... R
Potentiometer 1 ..................................................... P
PCB soldering pins 0.5 × 1.0 mm ......................... Y
1Option R excludes option P and vice versa.
Example: PSR 122.5-7iPY = A positive switching regulator with a 12 V, 2.5 A output, ambient temperature range of
–25…71°C, inhibit input, potentiometer and PCB soldering pins.
Control circuit
Go–
Vo+
Gi–
Vi+
Input Filter
R (option)
i (option)
I
o
U
o
I
i
U
i
03015
C
e
Option P
Fig. 1
Block diagram
Functional Description
The switching regulators are designed using the buck con-
verter topology. See also:
Technical Information: Topolo-
gies
. The input is not electrically isolated from the output.
During the on period of the switching transistor, current is
transferred to the output and energy is stored in the output
choke in the form of flux. During the off period, this energy
forces the current to continue flowing through the output,
to the load and back through the freewheeling diode.
Regulation is accomplished by varying the on to off duty
ratio of the power switch.
These regulators are ideal for a wide range of applica-
tions, where input to output isolation is not necessary, or
where already provided by an external front end (e.g. a
transformer with rectifier). To optimise customer’s needs,
additional options and accessories are available.
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Electrical Input Data
General Conditions:
T
A = 25°C, unless
T
C is specified
Table 2a: Input data
Input PSA 55 PSR 54 PSR 53 PSR 52
Characteristics Conditions min typ max min typ max min typ max min typ max Unit
U
iOperating input voltage
I
o = 0...
I
o nom 7 35 7 40 8 80 8 80 V DC
D
U
io min Min. diff. voltage
U
i –
U
o 1
T
C min...
T
C max 2233
U
i o Undervoltage lock-out 6.3 6.3 7.3 7.3
I
i 0 No load input current
I
o = 0,
U
i min...
U
i max 45 45 40 40 mA
I
inr p Peak value of inrush current
U
i nom 75 75 150 150 A
t
inr r Rise time 2.5 2.5 2.5 2.5 µs
t
inr h Time to half-value 15 15 15 15
u
i RFI Input RFI level, EN 55011/22
U
i nom,
I
o nom B 2 B 2 B 3 B 3
0.01...30 MHz
External Input Circuitry
The sum of the lengths of the supply lines to the source or
to the nearest capacitor ≥100 µF or to the nearest external
input filter which includes such a capacitor (a + b) should
not exceed 0.3 m (0.5 m twisted). An external input filter
(FP 38 or FP 80, see:
Accessory Products
) is recom-
mended in order to prevent power line oscillations and re-
duce superimposed interference voltages. See also:
Tech-
nical Information
:
Application Notes
.
Vi+
Gi–
Vo+
Go–
a
b
+
04016
Fig. 2
Switching regulator with long supply lines.
Table 2b: Input data
Input PSR 122.5 PSR 152.5 PSR 242 PSR 362
Characteristics Conditions min typ max min typ max min typ max min typ max Unit
U
iOperating input voltage
I
o = 0...
I
o nom 15 80 19 80 29 80 42 80 V DC
D
U
io min Min. diff. voltage
U
i –
U
o 1
T
C min...
T
C max 3456
U
i o Undervoltage lock-out 7.3 7.3 12 19
I
i 0 No load input current
I
o = 0,
U
i min...
U
i max 35 35 35 40 mA
I
inr p Peak value of inrush current
U
i nom 150 150 150 150 A
t
inr r Rise time 2.5 2.5 2.5 2.5 µs
t
inr h Time to half-value 15 15 15 15
u
i RFI Input RFI level, EN 55011/22
U
i nom,
I
o nom B 3 B 3 B 3 B 3
0.01...30 MHz
1The minimum differential voltage D
U
io min between input and output increases linearly by 0 to 1 V between
T
A = 46°C and 71°C
(
T
C = 70°C and 95°C)
2With input filter FP 38 (connected between Uii and Gi, see:
Accessory Products
) and
C
e = 470 µF/40 V
3With input filter FP 80 (connected between Uii and Gi, see:
Accessory Products
) and
C
e = 470 µF/100 V
PSR Series Switching Regulators, PCB & Chassis Industrial Environment
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Electrical Output Data
General Conditions:
–
T
A = 25°C, unless
T
C is specified
– With R or option P, output voltage
U
o =
U
o nom at
I
o nom
Table 3a: Output data
Output PSA 55 PSR 54 PSR 53 PSR 52
Characteristics Conditions min typ max min typ max min typ max min typ max Unit
U
oOutput voltage
U
i nom,
I
o nom 4.97 5.03 4.97 5.03 4.97 5.03 4.97 5.03 V
I
oOutput current 1
U
i min...
U
i max 0 5.0 3 0 4.0 0 3.0 0 2.0 A
I
oL Output current limitation
T
C min...
T
C max 5.0 6.5 4.0 5.2 3.0 3.9 2.0 2.6
response 1
u
oOutput Switching freq.
U
i nom,
I
o nom 20 35 15 25 20 35 20 35 mVpp
voltage Total IEC/EN 61204 2 24 39 19 29 24 39 24 39
noise BW = 20 MHz
D
U
o U Static line regulation
U
i min...
U
i max,
I
o nom 30 45 30 45 30 45 30 45 mV
D
U
o l Static load regulation
U
i nom,
I
o = 0...
I
o nom 20 25 20 25 20 25 20 25
u
o d Dynamic Voltage deviat.
U
i nom 250 200 100 100
t
dload Recovery time
I
o nom ↔ 1/3
I
o nom 40 40 50 50 µs
regulation IEC/EN 61204 2
aUo Temperature coefficient
U
i min...
U
i max ±1±1±1±1mV/K
D
U
o/D
T
C (
T
C min...
T
C max)
I
o = 0...
I
o nom ±0.02 ±0.02 ±0.02 ±0.02 %/K
Fig. 3
Dynamic load regulation.
I
o/
I
o nom
1
u
od
u
od
t
d
t
d
D
U
o I
D
U
o I
t
U
o
0
t
≥10 s
≥10 s
05010
Table 3b: Output data
Output PSR 122.5 PSR 152.5 PSR 242 PSR 362
Characteristics Conditions min typ max min typ max min typ max min typ max Unit
U
oOutput voltage
U
i nom,
I
o nom 11.93 12.07 14.91 15.09 23.86 24.14 35.78 36.22 V
I
oOutput current 1
U
i min...
U
i max 0 2.5 0 2.5 0 2.0 0 2.0 A
I
oL Output current limitation
T
C min...
T
C max 2.5 3.25 2.5 3.25 2.0 2.6 2.0 2.6
response 1
u
oOutput Switching freq.
U
i nom,
I
o nom 30 45 40 75 45 95 80 160 mVpp
voltage Total IEC/EN 61204 2 35 50 44 80 50 100 85 165
noise BW = 20 MHz
D
U
o U Static line regulation
U
i min...
U
i max,
I
o nom 50 75 70 100 150 220 200 270 mV
D
U
o l Static load regulation
U
i nom,
I
o = 0...
I
o nom 35 45 40 55 120 160 125 160
u
o d Dynamic Voltage deviat.
U
i nom 180 180 210 250
t
dload Recovery time
I
o nom ↔ 1/3
I
o nom 60 60 80 100 µs
regulation IEC/EN 61204 2
aUo Temperature coefficient
U
i min...
U
i max ±2±3±5±8mV/K
D
U
o/D
T
C (
T
C min...
T
C max)
I
o = 0...
I
o nom ±0.02 ±0.02 ±0.02 ±0.02 %/K
1See also:
Thermal Considerations.
2See:
Technical Information: Measuring and Testing.
3Linear derating from 5 to 4 A between
T
A = 61°C and 71°C (
T
C = 85°C and 95°C).
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Thermal Considerations
When a switching regulator is located in free, quasi-sta-
tionary air (convection cooling) at a temperature
T
A = 71°C
and is operated at its nominal output current
I
o nom, the
case temperature
T
C will be about 95°C after the warm-up
phase, measured at the
Measuring point of case tempera-
ture T
C (see:
Mechanical Data
).
Under practical operating conditions, the ambient tem-
perature
T
A may exceed 71°C, provided additional meas-
ures (heat sink, fan, etc.) are taken to ensure that the case
temperature
T
C does not exceed its maximum value of
95°C.
Example: Sufficient forced cooling allows
T
A max = 85°C. A
simple check of the case temperature
T
C (
T
C ≤ 95°C) at
full load ensures correct operation of the system.
1.2
1.0
0.8
0.6
0.4
00.2 0.4 1.0 1.2
0.2
0.6 0.8 1.4
U
o
/U
o nom
I
o
/I
o nom
I
o nom
I
o L
05033
Fig. 5
Overload, short-circuit behaviour U
o
versus I
o.
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
50 60 70 80 90 100
I
o
/I
o nom
T
A
[°C
]
0.9
1.0
Forced cooling
05031
T
A min
T
C max
Convection cooling
Parallel and Series Connection
Outputs of equal nominal voltages can be parallel-con-
nected. However, the use of a single unit with higher out-
put power, because of its power dissipation, is always a
better solution.
In parallel-connected operation, one or several outputs
may operate continuously at their current limit knee-point
which will cause an increase of the heat generation. Con-
sequently, the max. ambient temperature value should be
reduced by 10 K.
Outputs can be series-connected with any other module.
In series-connection the maximum output current is limited
by the lowest current limitation. Electrically separated
source voltages are needed for each module!
Short Circuit Behaviour
A constant current limitation circuit holds the output cur-
rent almost constant whenever an overload or a short cir-
cuit is applied to the regulator's output. It acts self-protect-
ing and recovers – in contrary to the fold back method –
automatically after removal of the overload or short circuit
condition.
Fig. 4
Output current derating versus temperature
Output Protection
A voltage suppressor diode which in worst case conditions
fails into a short circuit, protects the output against an in-
ternally generated overvoltage. Such an overvoltage could
occur due to a failure of either the control circuit or the
switching transistor. The output protection is not designed
to withstand externally applied overvoltages. The user
should ensure that systems with Melcher power supplies,
in the event of a failure, do not result in an unsafe condi-
tion (fail-safe).
Auxiliary Functions
LED Output Voltage Indicator
A yellow output indicator LED shines when the output volt-
age is higher than approx. 3 V.
The LED output voltage indicator is not available for
PSR 52.
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Electromagnetic Compatibility (EMC)
Electromagnetic Immunity
General condition: Case not earthed.
Table 4: Immunity type tests
Phenomenon Standard 1 Class Coupling Value Waveform Source Test In Per-
Level mode 2 applied Imped. procedure oper. form. 3
1 MHz burst IEC III i/o, i/c, o/c 2500 Vp400 damped 200 Ω2 s per yes A
disturbance 60255-22-1 +i/–i, +o/–o 1000 Vp1 MHz waves/s coupling mode
Voltage surge IEC 60571-1 i/c, +i/–i 800 Vp100 µs 100 Ωyes B
1500 Vp50 µs 1 pos. and 1 neg.
voltage surge per
coupling mode
3000 Vp5 µs
4000 Vp1 µs
7000 Vp100 ns
Electrostatic IEC/EN 3 contact discharge 6000 Vp1/50 ns 330 Ω10 positive and yes B 4
discharge 61000-4-2 to case 10 negative
discharges
Electromagnetic IEC/EN 2 antenna 3 V/m AM 80% 26…1000 MHz yes A
field 61000-4-3 1 kHz
Electrical fast IEC/EN 3 i/c, +i/–i 2000 Vpbursts of 5/50 ns 50 Ω1 min positive yes A 4
transient/burst 61000-4-4 4 4000 Vp5 kHz rep. rate 1 min negative B 4
transients with bursts per
15 ms burst coupling mode
duration and a
300 ms period
Surge IEC/EN 2 i/c 1000 Vp1.2/50 µs 12 Ω5 pos. and 5 neg. yes B 4
61000-4-5 +i/–i 500 Vp2 Ωsurges per
coupling mode
Conducted IEC/EN 3 i, o, signal wires 140 dBµV AM 80% 150 Ω0.15...80 MHz yes A
disturbances 61000-4-6 (10 Vrms) 1 kHz
1For related and previous standards see:
Technical Information: Safety & EMC
.
2 i = input, o = output, c = case.
3A = Normal operation, no deviation from specifications, B = Normal operation, temporary deviation from specs possible.
4External input filter FP 38 or FP 80 necessary.
Electromagnetic Emission
For emission levels refer to:
Electrical Input Data
.
07011
EN 55022 A
EN 55022 B
90
80
70
60
50
40
30
20
10
0
0
.01
0
.05
0.1
0.5
1
2
5
10
20
30
[dBµV]
MHz
0
.02
Fig. 6
Typical disturbance voltage (quasi-peak) at the input ac-
cording to EN 55011/22 measured at U
i nom
and I
o nom
.
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Immunity to Environmental Conditions
Table 5: Mechanical stress
Test Method Standard Test Conditions Status
Ca Damp heat IEC/DIN IEC 60068-2-3 Temperature: 40 ±2 °C Unit not
steady state MIL-STD-810D section 507.2 Relative humidity: 93 +2/-3 % operating
Duration: 56 days
Ea Shock IEC/EN/DIN EN 60068-2-27 Acceleration amplitude: 100 gn = 981 m/s2Unit
(half-sinusoidal) MIL-STD-810D section 516.3 Bump duration: 6 ms operating
Number of bumps: 18 (3 each direction)
Eb Bump IEC/EN/DIN EN 60068-2-29 Acceleration amplitude: 40 gn = 392 m/s2Unit
(half-sinusoidal) MIL-STD-810D section 516.3 Bump duration: 6 ms operating
Number of bumps: 6000 (1000 each direction)
Fc Vibration IEC/EN/DIN EN 60068-2-6 Acceleration amplitude: 0.7 mm (10...60 Hz) Unit
(sinusoidal) MIL-STD-810D section 514.3 10 gn = 98 m/s2 (60...2000 Hz) operating
Frequency (1 Oct/min): 10...2000 Hz
Test duration: 7.5 h (2.5 h each axis)
Fda Random vibration IEC 60068-2-35 Acceleration spectral density: 0.2 g2/Hz Unit
wide band DIN 40046 part 23 Frequency band: 20...500 Hz operating
Reproducibility Acceleration magnitude: 9.8 grms
high Test duration: 3 h (1 h each axis)
Kb Salt mist, cyclic IEC/EN/DIN IEC 60068-2-52 Concentration: 5% (30°C) Unit not
(sodium chloride Duration: 2 h per cycle operating
NaCl solution) Storage: 40°C, 93% rel. humidity
Storage duration: 22 h per cycle
Number of cycles: 3
Table 6: Temperature specifications, valid for air pressure of 800...1200 hPa (800...1200 mbar)
Temperature Standard -7 Option -9
Characteristics Conditions min max min max Unit
T
AAmbient temperature 1 Operational 2 –25 71 –40 71 °C
T
CCase temperature –25 95 –40 95
T
SStorage temperature 1 Non operational –40 100 –55 100
1MIL-STD-810D section 501.2 and 502.2
2See:
Thermal Considerations
Table 7: MTBF and device hours
MTBF Ground Fixed Ground Mobile Device Hours 1
MTBF acc. to MIL-HDBK-217D
T
C = 40°C
T
C = 70°C
T
C = 40°C
T
C = 70°C
160'000 70'000 h 45'000 h 22'000 h 5'100'000 h
1Statistical values, based on an average of 4300 working hours per year and in general field use.
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Mechanical Data
Dimensions in mm. Tolerances ±0.3 mm unless otherwise specified. European
Projection
Safety and Installation Instructions
Installation Instruction
Installation of the switching regulators must strictly follow
the national safety regulations in compliance with the enclo-
sure, mounting, creepage, clearance, casualty, markings
and segregation requirements of the end-use application.
Check for hazardous voltages before altering any connec-
tions. Connections can be made using fast-on or soldering
technique.
The input and the output circuit are not separated, i.e. the
negative path is internally interconnected!
The units should be connected to a secondary circuit.
Do not open the module.
Ensure that a unit failure (e.g. by an internal short-circuit)
does not result in a hazardous condition. See also:
Safety
of operator accessible output circuit.
2.8 x 0.5
(1.0 x 0.5 option Y)
min. 5
12.2
8.4
Ø 4
Potentiometer
(option P)
Yellow
LED output
voltage indicator
Go–iR
Gi–
20.5
6.3
18.7
1.2
8.75
65
47.5
±0.2
Measuring point
of case temperature
Vi+
Vo+
50.2
±0.2
2.7
±0.2
70.2
±0.5
6.5
±1
25.2
±0.5
7
±0.5
09015
Fig. 7
Case A01, weight 100 g
Aluminium, black finish
and self cooling
Fig. 8
Case A01 hole locations for circuit board layout (compo-
nent side view of PCB):
- - - = Space reserved for switching regulator
“a”= 3.0 mm x 0.7 mm slot or Ø 3.0 mm, through
plated for hand or machine soldering (fast on)
“a”=Ø 1.3...1.5 mm with option Y pins
20.5
6.3 18.7
1.2
8.75
71.4
51.4
a
47.5
±0.1
65
Distance between
M 2.5 mounting screws
09016
Cleaning Agents
In order to avoid possible damage, any penetration of
cleaning fluids is to be prevented, since the power sup-
plies are not hermetically sealed.
Protection Degree
The protection degree is IP 40, IP 20 with option P and for
PSR 52.
Isolation
Electric strength test voltage between input intercon-
nected with output and case: 750 V DC, 1 s.
This test is performed as factory test in accordance with
IEC/EN 60950 and UL 1950 and should not be repeated in
the field. Melcher will not honour any guarantee claims re-
sulting from electric strength field tests.
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Table 8: Insulation concept leading to an SELV output circuit
Conditions Front end Switching regulator Result
Supply Minimum required grade Maximum Minimum required safety Measures to achieve the Safety status of
voltage of isolation, to be provided DC output status of the front end specified safety status of the the switching
by the AC-DC front end, voltage output circuit output circuit regulator output
including mains supplied from the circuit
battery charger front end 1
Battery Double or Reinforced ≤60 V SELV circuit None SELV circuit
supply, >60 V Earthed hazardous voltage Input fuse 3 and earthed 4 Earthed SELV
considered secondary circuit 2 or non accessible case 5 circuit
as secon- Unearthed hazardous Input fuse 3 and unearthed, Unearthed SELV
dary circuit voltage secondary circuit 5 non accessible case 5 circuit
Hazardous voltage Input fuse 3 and earthed output Earthed SELV
secondary circuit circuit 4
and earthed 4 or non circuit
accessible case 5
Mains Basic ≤60 V Earthed SELV circuit 4 None
≤250 V AC ELV circuit Input fuse 3 and earthed output
>60 V Hazardous voltage circuit 4
and earthed 4 or non
secondary circuit accessible case 5
Double or reinforced ≤60 V SELV circuit None SELV circuit
>60 V Double or reinforced insu- Input fuse 3 and unearthed Unearthed SELV
lated unearthed hazardous and non accessible case 5 circuit
voltage secondary circuit 5
1The front end output voltage should match the specified input voltage range of the switching regulator.
2The conductor to the Gi– terminal of the switching regulator has to be connected to earth by the installer according to the relevant
safety standard, e.g. IEC/EN 60950.
3The installer shall provide an approved fuse (slow blow type with the lowest current rating suitable for the application, max. 12.5 A)
in a non-earthed input conductor directly at the input of the switching regulator. If Vo+ is earthed, insert the fuse in the Gi- line. For
UL’s purpose, the fuse needs to be UL-listed. If option C is fitted, a suitable fuse is already built-in in the Vi+ line.
4The earth connection has to be provided by the installer according to the relevant safety standard, e.g. IEC/EN 60950.
5Has to be insulated from earth by double or reinforced insulation according to the relevant safety standard, based on the maximum
output voltage from the front end.
Safety of Operator Accessible Output Circuit
If the output circuit of a switching regulator is operator-ac-
cessible, it shall be an SELV circuit according to IEC/EN
60950 related safety standards
The following table shows some possible installation con-
figurations, compliance with which causes the output cir-
cuit of the switching regulator to be an SELV circuit ac-
cording to IEC/EN 60950 up to a nominal output voltage of
30 V.
However, it is the sole responsibility of the installer or user
to assure the compliance with the relevant and applicable
safety regulations.
More information is given in:
Technical Information: Safety
& EMC
.
Standards and Approvals
All switching regulators are UL recognized according to UL
1950, UL 1012 and EN 60950, UL recognized for Canada
to CAN/CSA C22.2 No. 234-M90 and SEV approved to
IEC/EN 60950 and EN 55014 standards.
The units have been evaluated for:
•Building in,
•Operational insulation from input to output and input/
output to case,
•The use in an overvoltage category II environment,
•The use in a pollution degree 2 environment.
The switching regulators are subject to manufacturing sur-
veillance in accordance with the above mentioned UL and
CSA and with ISO 9001 standards.
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Table 9: Inhibit characteristics
Characteristics Conditions min typ max Unit
U
inh Inhibit input voltage to keep
U
o = on
U
i min...
U
i max –10 +0.8 V DC
regulator output voltage...
U
o = off
T
C min...
T
C max +2.4 +50
t
r Switch-on time after inhibit command
U
i =
U
i nom 2ms
t
f Switch-off time after inhibit command
R
L =
U
o nom /
I
o nom 4
I
i inh Input current when inhibited
U
i =
U
i nom 10 mA
0t
t
0
Inhibit
1
0.1
1
Uo/Uo nom
trtf
06001
Fig. 11
Output response as a function of inhibit signal
Description of Options
i Inhibit for Remote On and Off
Note: With open i-input, output is enabled (
U
o = on).
Not available for PSR 52.
The inhibit input allows the switching regulator output to be
disabled via a control signal. In systems with several units,
this feature can be used, for example, to control the activa-
tion sequence of the regulators by a logic signal (TTL, C-
MOS, etc.). An output voltage overshoot will not occur
when switching on or off.
Vi+
Gi–Go–
i
Vo+
I
inh
U
inh
06009
Fig. 10
Definition of I
inh
and U
inh
Fig. 9
Typical inhibit current I
inh
versus inhibit voltage U
inh
4
2
0
-50 -40 20 40
-30 0
-20 -10 10 30 50
5
3
1
I
inh
[mA]
U
inh
[V]
U
inh
= 0.8 V
U
inh
= 2.4 V
U
o
on U
o
off
06010
R Control for Output Voltage Adjustment
Note: With open R input,
U
o ≈ 1.08
U
o nom.
(Exception: With option Y,
U
o ≈ 1.00
U
o nom)
Option R excludes option P and vice versa.
Not available for PSR 52.
The output voltage
U
o can either be adjusted with an exter-
nal voltage (
U
ext) or with an external resistor (
R
1 or
R
2).
The adjustment range is 0...108% of
U
o nom. The minimum
differential voltage D
U
io min between input and output (see:
Electrical Input Data
) should be maintained. Under-volt-
age lock-out = Minimum input voltage.
Fig. 12
Voltage adjustment with U
ext
between R and Go–
a)
Without option Y: U
o = 0...108%
U
o nom, using
U
ext
2.5 V •
U
o
U
ext
U
ext ≈–––––––––––
U
o ≈ 1.08
U
o nom • –––––
1.08 •
U
o nom 2.5 V
b) With option Y:
U
o = 0...108%
U
o nom
2.5 V •
U
o
U
ext
U
ext ≈–––––––––
U
o ≈
U
o nom • –––––
U
o nom 2.5 V
Fig. 13
Voltage adjustment with external resistor R
1
or R
2
c) Without option Y:
U
o = 0...108%
U
o nom, using
R
1
4000 Ω •
U
o1.08 •
U
o nom •
R
1
R
1 ≈––––––––––––––
U
o ≈––––––––––––––
1.08 •
U
o nom –
U
o
R
1 + 4000 Ω
d) With option Y:
U
o = 0...100%
U
o nom, using
R
1
4000 Ω •
U
o
U
o nom •
R
1
R
1 ≈–––––––––––
U
o ≈–––––––––––
U
o nom –
U
o
R
1 + 4000 Ω
e) With option Y:
U
o = 100...108%
U
o nom, using
R
2
4000 Ω •
U
o • (
U
o nom – 2.5 V)
R
2 ≈––––––––––––––––––––––––
2.5 V • (
U
o –
U
o nom)
U
o nom • 2.5 V •
R
2
U
o ≈––––––––––––––––––––––––––––––––
2.5 V • (
R
2 + 4000 Ω) –
U
o nom • 4000 Ω
Vo+
R
+
4000 Ω
G
U
ref
U
ext
–
+
Go–
06035
Caution: To prevent damage
U
ext should not exceed
20 V, nor be negative and
R
2 should never be less than
47 kΩ.
Vo+
R–
+
G
4000 Ω
U
ref
R
1
R
2
Go–
06036
Industrial Environment Switching Regulators, PCB & Chassis PSR Series
Edition 4/4.99
11/11
MELCHER
The Power Partners.
-9 Extended Temperature Range
Note: Not available for PSR 52.
The operational ambient temperature range is extended to
T
A = –40...71°C. (
T
C = –40...95°C,
T
S = –55...100°C.)
Y PCB Soldering Pins
This option defines soldering pins of 1.0 × 0.5 × 6.5 mm,
instead of the standard fast-on terminals of 2.8 × 0.5 ×
6.5 mm. Modules with this option can be mounted onto
printed circuit boards, providing through-plated finished
hole size of Ø 1.3...1.5 mm.
The combination of option Y with option R will result in a
different setting of the output voltage (see also description
of:
R Control
).
Accessories
A variety of electrical and mechanical accessories are
available including:
–Isolation pads for easy and safe PCB-mounting.
–Filters and ring core chockes for ripple and interference
reduction.
–Adaptor kit for DIN-rail and chassis mounting.
PPotentiometer
Note: Not available for PSR 52.
Option P excludes option R. The output voltage
U
o can be
adjusted with a screwdriver in the range from 0.92...1.08 of
the nominal output voltage
U
o nom.
However, the minimum differential voltage D
U
iomin
be-
tween input and output voltages as specified in:
Electrical
Input Data
should be maintained.
