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SG7900A/SG7900 SERIES
SG7900A/SG7900
NEGATIVE FIXED VOLTAGE REGULATOR
DESCRIPTION
The SG7900A/SG7900 series of negative regulators offer self-contained, fixed-voltage capability with up to 1.5A of load current. With a variety of output voltages and four package options this regulator series is an optimum complement to the SG7800A/SG7800, SG140 line of three terminal regulators. These units feature a unique band gap reference which allows the SG7900A series to be specified with an output voltage tolerance of ±1.5%. The SG7900A versions also offer much improved line regulation characteristics. All protective features of thermal shutdown, current limiting, and safe-area control have been designed into these units and since these regulators require only a single output capacitor (SG7900 series) or a capacitor and 5mA minimum load (SG120 series) for satisfactory performance, ease of application is assured. Although designed as fixed-voltage regulators, the output voltage can be increased through the use of a simple voltage divider. The low quiescent drain current of the device insures good regulation when this method is used, especially for the SG120 series. These devices are available in hermetically sealed TO-257, TO-3, TO-39 and LCC package.
FEATURES
• • • • • • • • Output voltage set internally to ±1.5% on SG7900A Output current to 1.5A Excellent line and load regulation Foldback current limiting Thermal overload protection Voltages available: -5V, -12V, -15V Contact factory for other voltage options Available in surface mount package
HIGH RELIABILITY FEATURES - SG7900A/SG7900
♦ Available to MIL-STD - 883 ♦ MIL-M38510/11501BXA - JAN7905T ♦ MIL-M38510/11505BYA - JAN7905K ♦ MIL-M38510/11502BXA - JAN7912T ♦ MIL-M38510/11506BYA - JAN7912K ♦ MIL-M38510/11503BXA - JAN7915T ♦ MIL-M38510/11507BYA - JAN7915K ♦ LMI level "S" processing available
SCHEMATIC DIAGRAM
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For normal operation the (VOS) Sense Pin must be externally connected to the load.
12/91 Rev 1.4 12/99
Copyright 1999
1
11861 Western Avenue ∞ Garden Grove, CA 92841 (714) 898-8121 ∞FAX: (714) 893-2570
LINFINITY
Microelectronics Inc.
SG7900A/SG7900 SERIES
ABSOLUTE MAXIMUM RATINGS (Note 1)
Device Output Voltage -5V -12V -15V Operating Junction Temperature Hermetic (K, T, IG & L - Packages) ........................
Note 1. Values beyond which damage may occur.
NEGATIVE REGULATOR
Input Voltage -35V -35V -40V 150°C Input Voltage Differential (Output shorted to ground) 35V 35V 35V
Storage Temperature Range .......................... -65°C to 150°C Lead Temperature (Soldering, 10 Seconds) ................. 300°C
THERMAL DATA
K Package: Thermal Resistance-Junction to Case, θJC ................. 3.0°C/W Thermal Resistance-Junction to Ambient, θJA ............... 35°C/W T Package: Thermal Resistance-Junction to Case, θJC .................. 15°C/W Thermal Resistance-Junction to Ambient, θJA ............ 120°C/W IG Package: Thermal Resistance-Junction to Case, θJC ................. 3.5°C/W Thermal Resistance-Junction to Ambient, θJA .............. 42°C/W L Package: Thermal Resistance-Junction to Case, θJC .................. 35°C/W Thermal Resistance-Junction to Ambient, θJA ............ 120°C/W
Note A. Junction Temperature Calculation: TJ = TA + (PD x θJA). Note B. The above numbers for θJC are maximums for the limiting thermal resistance of the package in a standard mounting 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.
RECOMMENDED OPERATING CONDITIONS
(Note 2)
Operating Junction Temperature Range: SG7900A/7900 ............................................. -55°C to 150°C
Note 2. Range over which the device is functional.
CHARACTERISTIC CURVES
FIGURE 1. MAXIMUM AVERAGE POWER DISSIPATION
FIGURE 2. QUIESCENT CURRENT VS. LOAD
FIGURE 3. TEMPERATURE COEFFICIENT
12/91 Rev 1.4 12/99
Copyright 1999
2
11861 Western Avenue ∞ Garden Grove, CA 92841 (714) 898-8121 ∞FAX: (714) 893-2570
LINFINITY
Microelectronics Inc.
SG7900A/SG7900 SERIES
CHARACTERISTIC CURVES
(continued)
NEGATIVE REGULATOR
FIGURE 4. SHORTCIRCUIT CURRENT VS. VIN
FIGURE 5. QUIESCENT CURRENT VS. VIN
FIGURE 6. SHORT CIRCUIT CURRENT VS. VIN
FIGURE 7. DROPOUT CHARACTERISTICS
FIGURE 8. RIPPLE REJECTION VS. FREQUENCY
APPLICATIONS
FIGURE 9 - FIXED OUTPUT REGULATOR
FIGURE 10 - CIRCUIT FOR INCREASING OUTPUT VOLTAGE
NOTE: 1. C1 is required only if regulator is separated from rectifier filter. 2. Both C1 and C2 should be low E.S.R. types such as solid tantalum. If aluminum electrolytics are used, at least 10 times values shown should be selected. 3. If large output capacities are used, the regulators must be protected from momentary input shorts. A high current diode
NOTE: C3 optional for improved transient response and ripple rejec VOUT = V (REGULATOR) R 1 + R2 R1 R2 = V(REG) 15mA
12/91 Rev 1.4 12/99
Copyright 1999
3
11861 Western Avenue ∞ Garden Grove, C.