DESCRIPTION
The SG137A family of negative adjustable regulators will deliver up to 1.5A
output current over an output voltage range of -1.2V to -37V. Silicon General
has made significant improvements in these regulators compared to previous
devices, such as better line and load regulation, and a maximum output voltage
error of 1%. The SG137 family uses the same chip design and guarantees
maximum output voltage error of ±2%.
Every effort has been made to make these devices easy to use and difficult to
damage. Internal current and power limiting coupled with true thermal limiting
prevents device damage due to overloads or shorts even if the regulator is not
fastened to a heat sink.
The SG137A/137 family of products are ideal complements to the SG117A/
117 adjustable positive regulators.
FEATURES
••
••
•1 % output voltage tolerance
••
••
•0.01%/V line regulation
••
••
•0.5% load regulation
••
••
•0.02%/W thermal regulation
••
••
•Available in hermetic TO-220
HIGH RELIABILITY FEATURES
-SG137A/SG137
♦♦
♦♦
♦Available to MIL-STD-883 and DESC SMD
♦♦
♦♦
♦Scheduled for MIL-M38510 QPL listing
♦♦
♦♦
♦MIL-M38510/11804BYA - JAN137K
♦♦
♦♦
♦LMI level "S" processing available
SG137A/SG237A/SG337A
SG137/SG237/SG337
1.5 AMP NEGATIVE
ADJUSTABLE REGULATOR
BLOCK DIAGRAM
2/92 Rev 1.1 2/94 LINFINITY Microelectronics Inc.
Copyright 1994 11861 Western Avenue ∞ ∞
∞ ∞
∞ Garden Grove, CA 92841
1(714) 898-8121 ∞∞
∞∞
∞ FAX: (714) 893-2570
SG137A/SG137 SERIES
2/92 Rev 1.1 2/94 LINFINITY Microelectronics Inc.
Copyright 1994 11861 Western Avenue ∞ ∞
∞ ∞
∞ Garden Grove, CA 92841
2(714) 898-8121 ∞∞
∞∞
∞ FAX: (714) 893-2570
Power Dissipation ..........................................
Input to Output Voltage Differential ....................................
Storage Temperature Range ............................
ABSOLUTE MAXIMUM RATINGS (Note 1)
Internally Limited
40V
-65°C to 150°C
Operating Junction Temperature
Hermetic (K, R, T, L, IG-Packages) ...........................
Lead Temperature (Soldering, 10 Seconds) ............. 150°C
300°C
Note 1. Exceeding these ratings could cause damage to the device.
RECOMMENDED OPERATING CONDITIONS (Note 2 & 3)
Input Voltage Range .............................. -(VOUT + 3.5V) to -36V Operating Junction Temperature Range
SG137A/SG137 ............................................
SG237A/SG237 ............................................
SG337A/SG337 .............................................
-55°C to 150°C
-25°C to 150°C
0°C to 125°C
Note 2. Range over which the device is functional.
Note 3. These ratings are applicable for junction temperatures of less than 135°C.
ELECTRICAL CHARACTERISTICS
(Unless otherwise specified, these specifications apply over full operating ambient temperatures for SG137A/SG137 with -55°C ≤ TA ≤ 150°C, SG237A/
SG237 with -25°C ≤ TA ≤ 150°C, SG337A/SG337 with 0°C ≤ TA ≤ 125°C, |VIN - VOUT| = 5.0V, and for IOUT = 500mA (K, R, and IG power packages) and IOUT
= 100mA (T and L packages). Although power dissipation is internally limited, these specifications are applicable for power dissipations of 2Ω for the T and
L packages, and 20Ω for the K, R, and IG packages. IMAX is 1.5A for the K, R, and IG packages and 0.5A for the T and L packages. Low duty cycle pulse
testing techniques are used which maintains junction and case temperatures equal to the ambient temperature.)
THERMAL DATA
K Package:
Thermal Resistance-Junction to Leads, θJC................ 3.0°C/W
Thermal Resistance-Junction to Ambient, θJA ............... 35°C/W
R Package:
Thermal Resistance-Junction to Leads, θJC................ 5.0°C/W
Thermal Resistance-Junction to Ambient, θJA .............. 40°C/W
T Package:
Thermal Resistance-Junction to Leads, θJC................. 15°C/W
Thermal Resistance-Junction to Ambient, θJA ............ 120°C/W
IG Package:
Thermal Resistance-Junction to Leads, θJC................ 3.5°C/W
Thermal Resistance-Junction to Ambient, θJA .............. 42°C/W
L Package:
Thermal Resistance-Junction to Leads, θJC................. 35°C/W
Thermal Resistance-Junction to Ambient, θJA ............ 120°C/W
Units
SG137/SG237
Min. Typ. Max.
Min. Typ. Max.
SG137A/SG237A
Parameter Test Conditions
IOUT = 10mA, TA = 25°C
3V ≤ |VIN - VOUT| ≤ 40V, 10mA ≤ IOUT ≤ IMAX
3V ≤ |V IN - VOUT| ≤ 40V, IOUT ≤ IMAX
TA = 25°C
10mA ≤ IOUT ≤ IMAX
|VOUT| ≤ 5V, TA = 25°C
|VOUT| ≥ 5V, TA = 25°C
|VOUT| ≤ 5V
|VOUT| ≥ 5V
TA = 25°C, 10ms pulse
VOUT = -10V, f =120Hz
CADJ = 0, TA = 25°C
CADJ = 10µF
TA = 25°C
3V ≤ |VIN - V OUT| ≤ 40V
10mA ≤ IOUT ≤ IMAX
Reference Voltage (Note 6)
Line Regulation (Note 4, 6)
Load Regulation (Note 4)
Thermal Regulation (Note 5)
Ripple Rejection
Adjust Pin Current
Adjust Pin Current Change
(Note 6)
-1.238
-1.220
60
70
-1.250
-1.250
0.005
5
0.1
10
0.2
0.002
66
80
65
1.0
0.2
-1.262
-1.280
0.01
25
0.5
50
1.0
0.02
100
5
2
-1.225
-1.200
66
-1.250
-1.250
0.01
15
0.3
20
0.3
0.002
60
77
65
2
0.5
-1.275
-1.300
0.02
25
0.5
50
1.0
0.02
100
5
5
V
V
%/V
mV
%
mV
%
%/W
dB
dB
µA
µA
µA
Note A. Junction Temperature Calculation: TJ = TA + (P D x θJA).
Note B. The above numbers for θJC are maximums for the limiting
thermal resistance of the package in a standard mount-
ing configuration. The θJA numbers are meant to be
guidelines for the thermal performance of the device/pc-
board system. All of the above assume no ambient
airflow.
SG137A/SG137 SERIES
2/92 Rev 1.1 2/94 LINFINITY Microelectronics Inc.
Copyright 1994 11861 Western Avenue ∞ ∞
∞ ∞
∞ Garden Grove, CA 92841
3(714) 898-8121 ∞∞
∞∞
∞ FAX: (714) 893-2570
-1.262
-1.280
0.01
25
0.5
50
1.0
0.02
100
5
2
5
3
3.5
1.5
1.0
0.5
1.5
1.0
-1.250
-1.250
0.01
15
0.3
20
0.3
0.003
60
77
65
2
0.5
2.5
1
2.2
0.8
0.4
0.17
0.6
0.3
0.003
-1.287
-1.300
0.04
50
1.0
70
1.5
0.04
100
5
5
10
6
1.0
Reference Voltage (Note 6)
Line Regulation (Note 4, 6)
Load Regulation (Note 4)
Thermal Regulation (Note 5)
Ripple Rejection
Adjust Pin Current
Adjust Pin Current Change
(Note 6)
Minimum Load Current
Current Limit
Temperature Stability (Note 5)
Long Term Stability (Note 5)
RMS Output Noise (% of VOUT)
ELECTRICAL CHARACTERISTICS (continued)
Units
SG337
Min. Typ. Max.
Min. Typ. Max.
SG337A
Test ConditionsParameter Units
SG137/SG237
Min. Typ. Max.Min. Typ. Max.
SG137A/SG237A
|VIN - VOUT| ≤ 40V
|VIN - VOUT| ≤ 10V
|VIN - VOUT| ≤ 15V
K, P, R, IG Packages
T, L, Packages
|VIN - VOUT| ≤ 40V, TJ = 25°C
K, P, R, IG Packages
T, L, Packages
TA = 125°C, 1000 Hours
TA = 25°C, 10Hz ≤ f ≤ 10 KHz (Note 5)
Minimum Load Current
Current Limit
Temperature Stability (Note 5)
Long Term Stability (Note 5)
RMS Output Noise (% of VOUT)
1.5
0.5
0.24
0.15
2.5
1.2
2.2
0.8
0.4
0.25
0.6
0.3
0.003
5.0
3
3.2
1.5
1.0
0.5
1.5
1.0
1.5
0.5
0.24
0.15
2.5
1.2
2.2
0.8
0.4
0.25
0.6
0.3
0.003
5.0
3.0
1.0
mA
mA
A
A
A
A
%
%
%
-1.238
-1.220
60
70
1.5
0.5
0.24
0.15
-1.250
-1.250
0.005
5
0.1
10
0.2
0.002
66
80
65
1.0
0.2
2.5
1.2
2.2
0.8
0.5
0.25
0.6
0.3
0.003
-1.213
-1.200
66
1.5
0.5
0.15
0.10
V
V
%/V
mV
%
mV
%
%/W
dB
dB
µA
µA
µA
mA
mA
A
A
A
A
%
%
%
IOUT = 10mA, TA = 25°C
3V ≤ |VIN - VOUT| ≤ 40V, 10mA ≤ IOUT ≤ IMAX
3V ≤ |V IN - VOUT| ≤ 40V, IOUT ≤ IMAX
TA = 25°C
10mA ≤ IOUT ≤ IMAX
|VOUT| ≤ 5V, TA = 25°C
|VOUT| ≥ 5V, TA = 25°C
|VOUT| ≤ 5V
|VOUT| ≥ 5V
TA = 25°C, 10ms pulse
VOUT = -10V, f =120Hz
CADJ = 0, TA = 25°C
CADJ = 10µF
TA = 25°C
3V ≤ |VIN - V OUT| ≤ 40V
10mA ≤ IOUT ≤ IMAX
|VIN - VOUT| ≤ 40V
|VIN - VOUT| ≤ 10V
|VIN - VOUT| ≤ 15V
K, P, R, IG-Packages
T, L-Packages
|VIN - VOUT| ≤ 40V, TJ = 25°C
K, P, R, IG- Packages
T, L-Packages
TA = 125°C, 1000hr
TA = 25°C, 10Hz ≤ f ≤ 10KHz (Note 5)
Test ConditionsParameter
Note4. Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle. Changes in output voltage due to heating
effects are covered under the specification for thermal regulation.
Note 5. These parameters, although guaranteed, are not tested in production.
Note 6. IMAX for K, R, and IG packages is VIN - VOUT = 3V / 1.5A and VIN - VOUT = 40V / 240mA. For T and L packages I MAX is VIN - VOUT = 3V / 500mA
and VIN - VOUT = 40V / 150mA.
SG137A/SG137 SERIES
2/92 Rev 1.1 2/94 LINFINITY Microelectronics Inc.
Copyright 1994 11861 Western Avenue ∞ ∞
∞ ∞
∞ Garden Grove, CA 92841
4(714) 898-8121 ∞∞
∞∞
∞ FAX: (714) 893-2570
FIGURE 6.
ADJUSTMENT CURRENT VS. TEMPERATURE
FIGURE 5.
INPUT/OUTPUT DIFFERENTIAL
VS. OUTPUT CURRENT
FIGURE 3.
CURRENT VS. INPUT/OUTPUT DIFFERENTIAL
FIGURE 2.
REFERENCE VOLTAGE VS. TEMPERATURE
FIGURE 1.
INPUT/OUTPUT DIFFERENTIAL
VS. OUTPUT CURRENT
FIGURE 4. *
OUTPUT VOLTAGE DEVIATION
VS. OUTPUT CURRENT
CHARACTERISTIC CURVES
* The SG137A has load regulation compensation which
makes the typical unit read close to zero. This band
represents the typical production spread.
APPLICATION INFORMATION
OUTPUT VOLTAGE
The output voltage is determined by two external resistors, R 1 &
R2(see Figure 7).
The exact formula for the output voltage is:
VOUT = VREF + IADJ (R2)
( )
Where: VREF =Reference Voltage, IADJ = Adjustment Pin Current.
In most applications, the second term is small enough to be
ignored, typically about 0.5% of VOUT. In more critical applica-
tions, the exact formula should be used, with IADJ equal to 65µA.
Solving for R2 yields:
Smaller values of R1 and R2 will reduce the influence of I ADJ on the
output voltage, but the no-load current drain on the regulator will
be increased. Typical values for R1 are between 100Ω and 300Ω,
giving 12.5 mA and 4.2mA no-load current respectively. There
is an additional consideration in selecting R1 the minimum load
current specification of the regulator. The operating current of
R2 =VOUT - VREF
VREF
R1+ IADJ
FIGURE 6
R2 + R1
R1
SG137A/SG137 SERIES
2/92 Rev 1.1 2/94 LINFINITY Microelectronics Inc.
Copyright 1994 11861 Western Avenue ∞ ∞
∞ ∞
∞ Garden Grove, CA 92841
5(714) 898-8121 ∞∞
∞∞
∞ FAX: (714) 893-2570
APPLICATION INFORMATION (continued)
the SG137A flows from input to output. If this current is not
absorbed by the load, the output of the regulator will rise above
the regulated value. The current drawn by R1 and R2 is normally
high enough to absorb the current, but care must be taken in no–
load situations where R 1 and R2 have high values. The maximum
value for the operating current, which must be absorbed, is 5mA
for the SG137A, If input-output voltage differential is less than
10V, the operating current that must be absorbed drops to 3mA.
The output stability, load regulation, line regulation, thermal
EXAMPLES:
1. A precision 10V regulator to supply up to 1Amp load current.
a. Select R1 = 100Ω to minimize effect of IADJ
b. Calculate R2 = = = 704W
2. A 15V regulator to run off batteries and supply 50mA.
VIN MAX = 25V
a. To minimize battery drain, select R1 as high as possible
R1 = = 417Ω, use 404Ω, 1%
VOUT - VREF
(VREF/R1) + IADJ
10V - 1.25V
(1.25V/100W) + 65mA
1.25V
3mA
TYPICAL APPLICATIONS
regulation, temperature drift, long term drift, and noise, can be
improved by a factor of 6.6 over the standard regulator configu-
ration. This assumes a zener whose drift and noise is considera-
bly better than the regulator itself. The LM329B has 20PPM/°C
maximum drift and about 10 times lower noise than the regulator.
In the application shown Figure 8, regulators #2 to #N will track
regulator #1 to within ±24mV initially, and to ±60mV over all load,
line, and temperature conditions. If any regulator output is
shorted to ground, all other outputs will drop to -2V. Load
regulation of regulators #2 to #N will be improved by VOUT/1.25V
compared to a standard regulator, so regulator #1 should be the
one which has the lowest load current.
FIGURE 11 - DUAL TRACKING SUPPLY ±1.25V to ±20VFIGURE 10 - CURRENT REGULATOR
FIGURE 9 - HIGH STABILITY REGULATOR
FIGURE 8 - MULTIPLE TRACKING REGULATORS
SG137A/SG137 SERIES
2/92 Rev 1.1 2/94 LINFINITY Microelectronics Inc.
Copyright 1994 11861 Western Avenue ∞ ∞
∞ ∞
∞ Garden Grove, CA 92841
6(714) 898-8121 ∞∞
∞∞
∞ FAX: (714) 893-2570
CONNECTION DIAGRAMS & ORDERING INFORMATION (See Notes Below)
Ambient
Temperature Range
Part No.Package Connection Diagram
3-TERMINAL TO-3
METAL CAN
K-PACKAGE
SG137AK/883B -55°C to 125°C
SG137AK/DESC -55°C to 125°C
SG137AK -55°C to 125°C
SG237AK -25°C to 85°C
SG337AK 0°C to 70C
SG137K/883B -55°C to 125°C
JAN137K -55°C to 125°C
SG137K/DESC -55°C to 125°C
SG137K -55°C to 125°C
SG237K -25°C to 85°C
SG337K 0°C to 70°C
2
1
ADJUSTMENT
CASE IS VIN
VOUT
3-TERMINAL TO-66
METAL CAN
R-PACKAGE
SG137AR/883B -55°C to 125°C
SG137AR/DESC -55°C to 125°C
SG137AR -55°C to 125°C
SG237AR -25°C to 85°C
SG337AR 0°C to 70°C
SG137R/883B -55°C to 125°C
SG137R/DESC -55°C to 125°C
SG137R -55°C to 125°C
SG237R -25°C to 85°C
SG337R 0°C to 70°C
1
2
ADJUSTMENT
VOUT
CASE IS VIN
3-PIN TO-39 METAL CAN
T-PACKAGE SG137AT/883B -55°C to 125°C
SG137AT/DESC -55°C to 125°C
SG137AT -55°C to 125°C
SG237AT -25°C to 85°C
SG337AT 0°C to 70°C
SG137T/883B -55°C to 125°C
SG137T/DESC -55°C to 125°C
SG137T -55°C to 125°C
SG237T -25°C to 85°C
SG337T 0°C to 70°C
32 VIN
VOUT
ADJUSTMENT 1
3-PIN HERMETIC TO-257
IG-PACKAGE (Isolated) SG137AIG/883B -55°C to 125°C
SG137AIG/DESC -55°C to 125°C
SG137AIG -55°C to 125°C
SG137IG/883B -55°C to 125°C
SG137IGDESC -55°C to 125°C
SG137IG -55°C to 125°C
20-PIN CERAMIC (LCC)
LEADLESS CHIP CARRIER
L- PACKAGE
SG137AL/883B -55°C to 125°C
SG137AL/DESC -55°C to 125°C
SG137AL -55°C to 125°C
SG137L/883B -55°C to 125°C
SG137L/DESC -55°C to 125°C
SG137L -55°C to 125°C
4
5
6
7
8
321
911121310
14
15
16
17
18
20 19 11. VIN
12. N.C.
13. N.C.
14. N.C.
15. N.C.
16. ADJUST
17. N.C.
18. N.C.
19. N.C.
20. N.C.
1. VOUT
2. VOUT
3. N.C.
4. N.C.
5. N.C.
6. N.C.
7. N.C.
8. N.C.
9. N.C.
10. N.C.
(Note 4)
ADJUST
VOUT
VIN
Not e 1. Contact factory for JAN and DESC product availability.
2. All parts are viewed from the top. 3. Product is also available in flatpack. Consult factory for price and delivery.
4. Both outputs must be externally connected together at the device terminals.
