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GS-R12HXXX2
October 2003
This is preliminary information on a new product now in development. Details are subject to change without notice.
FEATURE
s
MTBF 1 000 000 hours (T
amb
=25
)
C)
s
2A max output current
s
35V max input voltage
s
1.5V max drop-out voltage
s
3.3V 2% reference voltage
s
Remote logic inhibit/enable
s
Synchronization
s
Not-latching overload and short circuit
protection
s
Thermal shutdown
s
Fixed or adjustable output
s
No heatsink required
DESCRIPTION
The GS-R12HXXX2 series is a family of high efficiency step down switching voltage regulator, designed to re-
place linear regulators.
Based on STM L5973 device, this non isolated family of regulators are suitable for the full spectrum of applica-
tions including telecom, industry, computer and distributed power system applications having a widely ranging
input voltage.
SELECTION CHART
Type
Ordering
Number
Output
Voltage
[V]
Input
Voltage
[V]
Output
Ripple
[mVpp]
Efficiency
[%]
Notes
GS-R12H0122
1.235
3
%
4.5
15
20
68
Fixed output voltage
GS-R12H0182
1.8
4
%
4.5
15
20
72
Fixed output voltage
GS-R12H0252
2.5
4
%
4.5
15
20
76
Fixed output voltage
GS-R12H0332
3.3
4
%
4.5
15
20
82
Fixed output voltage
GS-R12H0502
5.0
4
%
6.6
15
20
85
Fixed output voltage
GS-R12H0002
1.235
5.0
4.5
15
20
68
85
Progr. output voltage
GS-R24H0332
3.3
4
%
16
35
20
82
Fixed output voltage
ORDERING NUMBER: GS-R12HXXX2
PRELIMINARY
2.5W TO 24W STEP-DOWN SWITCHING REGULATOR FAMILY
GS-R12HXXX2
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ABSOLUTE MAXIMUM RATINGS
GS-R24H0502
5.0
4
%
16
35
20
85
Fixed output voltage
GS-R24H1201.5
12
4
%
16
35
100
91
Fixed output voltage
GS-R24H0001
3.3
24
16
35
100
250
78
96
Progr. output voltage
Symbol
Parameter
Value
Unit
Vi
DC Input Voltage (for GS-R12HXXX2)
16
V
DC Input Voltage (for GS-R24HXXX)
36
V
I
out
Maximum Output Current
int. limit
V
9
INH
-0.3 to V
i
V
V
10
Sync
-0.3 to 4
V
V
11
FB
4
V
T
stg
Storage Temperature Range
-40
105
C
T
op
Operating Ambient Temperature
-25
70
C
T
op1
Operating Ambient Temperature with current derating
-25
85
C
Type
Ordering
Number
Output
Voltage
[V]
Input
Voltage
[V]
Output
Ripple
[mVpp]
Efficiency
[%]
Notes
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GS-R12HXXX2
CONNECTION DIAGRAM AND MECHANICAL DATA
PIN DESCRIPTION
Pin
Function
Description
1
Input GND
Return for input voltage source
2
Input GND
Return for input voltage source
3
Input GND
Return for input voltage source
4
Input +
DC input voltage
5
Input +
DC input voltage
6
Input +
DC input voltage
7
Input +
DC input voltage
8
V
ref
3.3V reference voltage
9
INH
A logical level (active high) disables the device, when it is open an internal pull
up disables the device
10
Sync
Master/Slave synchronization
11
FB
Feedback input, available on adjustable device
12
V
out
Regulated output
13
V
out
Regulated output
GS-R12HXXX2
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ELECTRICAL CHARACTERISTICS All versions (T
amb
=25
)
C, unless otherwise specified.)
ELECTRICAL CHARACTERISTICS for GS-R12HXXX2 only (T
amb
=25
)
C, unless otherwise specified.)
14
V
out
Regulated output
15
V
out
Regulated output
16
Output GND
Return for output voltage
17
Output GND
Return for output voltage
18
Output GND
Return for output voltage
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
Temperature Stability
V
i
=V
o
+ 1.5V I
o
= 2A
mV/C
I
oL
Current Limit
V
i
=4.5
15V
2.5
A
I
q
Quiescent Current
V
i
=12V I
o
= 0A
1.8
2.5
mA
I
qst-by
Total Stand-by Quiescent
Current
V
inh
>2.2V
50
100
A
f
s
Switching Frequency
V
i
=12V I
o
= 1.5A
225
250
275
kHz
V
ref
Reference Voltage
V
i
=4.5
15V I
ref
=0
5mA
3.234
3.3
3.366
V
Short Circuit Current
8
10
30
mA
INH
INH Threshold Voltage
Device ON
0.8
V
Device OFF
2.2
V
V
FB
Feedback voltage
V
i
=4.5
15V I
o
= 0
2A
1.22
1.235
1.25
V
SRV
Supply Voltage Rejection
mV/V
R
th
Thermal Resistance
Case to ambient
C/W
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
I
o
Output Current
V
i
=4.5
15V
0
2
A
V
r
Ripple Voltage
V
i
=12V I
o
= 2A
20
mVpp
Pin
Function
Description
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GS-R12HXXX2
ELECTRICAL CHARACTERISTICS for GS-R24HXXX only (T
amb
=25
)
C, unless otherwise specified.)
USER NOTES
Input Voltage
The recommended operating maximum DC Input Voltage is 15V inclusive of ripple voltage.
Reference voltage
No capacitor is required for stability.
Inhibit function
The inhibit feature allows to put in stand-by mode the device.
With INH pin 9 higher than 2.2V the device is disabled and the power consumption is reduced to less than
100A.
With INH pin lower than 0.8V, the device is enabled.
If the INH pin is left floating, an internal pull up ensures that the voltage at the pin reaches the inhibit threshold
and the device is disabled.
The pin is also V
cc
compatible.
Multiple units synchronization
Using more than one unit on the same circuit, it is possible to synchronize the switching frequency, connecting
all pin 10 together (see figure 3).
The unit with higher frequency becomes the master.
Current protection
The device has two current limit protections, pulse by pulse and frequency fold back.
The current is sensed through a resistor and if reaches the threshold, the on time is reduced and consequently
the output voltage too.
Since the minimum switch ON time (necessary to avoid false overcurrent signal) is not enough to obtain a suf-
ficiently low duty cycle at 250 Hz, the output current, in strong overcurrent or short circuit conditions, could in-
crease again.
For this reason the switching frequency is also reduced, so keeping the inductor current under its maximum
threshold.
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
I
o
Output Current
V
i
=16
35V for GS-R24H0332
---------------------
GS-R24H0502
0
2
A
I
o
Output Current
V
i
=16
35V for GS-R24H1201.5
0
1.5
A
I
o
Output Current
V
i
=16
35V for GS-RH0001
0
1-2
A
V
r
Ripple Voltage
V
i
=24V I
o
= 2A for GS-R24H0332
--------------------- -
GS-R24H0502
20
mVpp
V
r
Ripple Voltage
V
i
=24V I
o
= 2A for GS-R24H1201.5
100
mVpp
V
r
Ripple Voltage
V
i
=24V I
o
= 2A for GS-R24H0001
100-
250
mVpp
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