SCD8687 Rev B
❑Manufactured using Linear Technology Corporation ® Space Qualified RH1084 die
❑Radiation performance
- Total dose > 100 krad (Si),
Dose rate = 50 - 300 rads(Si)/s
❑Two-Independent voltage regulators
❑Thermal shutdown
❑Output voltage adjust able: 1.25V to 23V
❑Dropout voltage: 1.80V at 3.0Amps
❑3-Terminal
❑Output current: 3.0Amps
❑Voltage reference: 1.25V +2%, -3.2%
❑Load regulation: 0.35% max
❑Line regulation: 0.25% max
❑Ripple rejection: >60dB
❑Packaging – Hermetic metal
- Thru-hole or Surface mount
- 8 Leads, .755"L x .415"W x .200"Ht
- Power package
- Weight - 6 gm max
❑Designed for aerospace and high reliability space
applications
DESCRIPTION
The Aeroflex Plainview VRG8687/8688 consists of two Positive Adjustable (RH1084) LDO voltage regulators each
capable of supplying 3.0Amps over the output voltage range as defined under recommended operating conditions. The
VRG8687/8688 offers excellent line and load regulation specifications and ripple rejection. There is full electrical
isolation between the regulators and each regulator to the package.
Dropout (VIN - VOUT) decreases at lower load curr ents for both regulators.
The VRG8687/8688 serves a wide variety of applications including SCSI-2 Active Terminator, High Efficiency
Linear Regulators, Post Regulators for Switching Supplies, Constant Current Regulators, Battery Chargers and
Microprocessor Supply.
The VRG8687/8688 has been specifically designed to meet exposure to radiation environments. The VRG8687 is
configured for a Thru-Hole 8 lead metal power package and the VRG8688 is configured for a Surface Mount 8 lead
metal power package. It is guaranteed operational from -55°C to +125°C. Available screened in accordance with
MIL-PRF-38534, the VRG8687/8688 is ideal for demanding military and space applications.
For detailed performance characteristic curves, applications information and typical applications see the
latest Linear Technology Corporation®data sheets for their RH/LT1084, which is available on-line at
www.linear.com.
Radiation Tolerant
FIGURE 1 – BLOCK DIAGRAM / SCHEMATIC
October 24, 2011
www.aeroflex.com/voltreg
Standard Products
FEATURES
VRG8687/VRG8688
Dual Voltage Regulator, 3.0 Amp, Positive
4
V
IN
_2
A
DJ
_2
V
OUT
_2
5
8
V
IN
_1
A
DJ
_1
V
OUT
_1
1
2 6
RH1084
Positive
Regulator
RH1084
Positive
Regulator
Low Dropout (LDO), Adjustable
3 7
S
ENSE
_2S
ENSE
_1
❑Aeroflex Plainview’s Radiation Hardness Assurance Plan is DLA Certified to MIL-PRF-38534, Appendix G.
2
SCD8687 Rev B 10/24/11 Aeroflex Plainview
ABSOLUTE MAXIMUM RATINGS
Parameter Range Units
Input Volta ge +25 VDC
Lead temperature (soldering 10 Sec) 300 °C
Input Output Differential 25 VDC
Load Current, maximum 6.0 A
Output Voltage +25 VDC
ESD (MIL-STD-883, M3015, Class 2) 2000 to 3999 V
Operating Junction Temperature Range -55 to +150 °C
Storage Temperature Range -65 to +150 °C
Thermal Resistance, Junction to case JC 5°C/W
NOTICE: Stresses above those listed under "Absolute Maximums Rating" may cause perma nent damage to the device. These are
stress rating only; functional operation beyond the "Operation Conditions" is not recommended and extended exposure
beyond the "Operation Conditions" may effect device reliability.
RECOMMENDED OPERATING CONDITIONS
Parameter Range Units
Output Voltage Range 1.25 to 23 VDC
Input Output Differential 3/ 1.8 to 24 VDC
Case Operating Temperature Range -55 to +125 °C
ELECTRICAL PERFORMANCE CHARACTERISTICS 1/
UNLESS OTHERWISE SPECIFIED: -55°C TC +125°C
Parameter Symbol Conditions (PPMAX)Min Max Units
Reference Voltage 3/, 2/VREF 1.5V < (VIN - VOUT) < 15V, 10mA < IOUT < 3.0A 1.210 1.275 V
Line Regulation 3/, 2/ILOAD = 10mA, 1.5V < (VIN - VOUT) < 15V - 0.25 %
Load Regulation 3/, 2/ 10mA < IOUT < 3.0A, (VIN - VOUT) = 3V - 0.35 %
Dropout Voltage 4/, 2/VDROP VREF = 1%, IOUT = 3.0A -1.8V
Adjust Pin Current 2/- -120µA
Adjust Pin Current Chan ge 2/ - 10 mA < IOUT < 3.0A, 1.5V < (VIN - VOUT) < 15V - 5 µA
Minimum Load Current 5/, 2/IMIN (VIN - VOUT) = 25V - 10 mA
Current Limit 2/ICL (VIN - VOUT) = 5V 5.25 - A
Ripple Rejection 3/-
IOUT = 3.0A, (VIN - VOUT) = 3V, f = 120Hz,
CADJ = COUT = 25µF 60 - dB
Thermal Regulation - 30ms pulse, TC = +25°C - 0.015 %/W
VREF Long-Term Stability 5/ - Burn In: TC = +125°C@1000hrs minimum, tested @ 25°C - 1.0 %
Notes:
1/ The manufacturer’s output current rating for the RH1084MK positive regulator integrated circuit is 5.0 Amps. For Compliance with the
Current Density specifictation of MIL-STD-883 Rev. C, the electrical performance characteristics are specified at an output current of
3.0 Amps.
2/ Specification derated to reflect total dose exposure to 100krads (Si) at +25°C.
3/ Line and load regulation are guaranteed up to the maximum power dissipation of 15W per device. Power dissipation is determined by
the input/output differential voltage and the output current. Guaranteed maximum power dissipation will not be available over the full
input/output voltage range.
4/ Dropout voltage is specified over the full output current rang e of th e de vi ce .
5/ Not tested. Shall be guaranteed by design, characterization, or correlation to other tested parameters.
VOUT
VIN
VOUT
IOUT
3
SCD8687 Rev B 10/24/11 Aeroflex Plainview
FIGURE 3 – RH1084 SHORT CIRCUIT CURRENT
The maximum Power dissipation is limited by the thermal shutdown function of each regulator chip in the
VG8687/8688. The graph above represents the achievable power before the chip shuts down. The first line in the
graph represents the maximum power dissipation of the VG8687/8688 with one regulator on (the other off) and the
other line represents both regulators on dissipating equal power. If both regulators are on and one regulator is
dissipating more power that the other, the maximum power dissipation of the VG8687/8688 will fall between the two
lines. This graph is based on the maximum junction temperature of 150°C and a thermal resistance (JC) of 5°C/W.
60
50
40
30
20
10
0 20406080100120140
Case Temperature (°C)
1 Regulator
0
Both Regulators
Maximum Power
Dissipation
(Watts)
FIGURE 2 – MAXIMUM POWER vs CASE TEMPERATURE
See Note 1/ on page 2
4
SCD8687 Rev B 10/24/11 Aeroflex Plainview
VRG8687/88
VIN VOUT
ADJ
R1
R2
VREF 22µF
Tant.
IADJ = 55µAVREF = 1.25V,
+Reg = VOUT = VREF (1+R2/R1) + (IADJ x R2)
FIGURE 5 – BASIC RH1084 ADJUSTABLE REGULATOR APPLICATION
SENSE
10µF
Tant.
FIGURE 4 – RH1084 DROPOUT VOLTAGE TYPICAL CURVE
5
SCD8687 Rev B 10/24/11 Aeroflex Plainview
FIGURE 5 – VRG8687 PACKAGE OUTLINE — THRU-HOLE POWER PACKAGE
TABLE I – PIN NUMBERS vs FUNCTION
PIN FUNCTION
1ADJ_1
2VOUT_1
3 SENSE_1
4VIN_2
5ADJ_2
6VOUT_2
7 SENSE_2
8VIN_1
ø
.145 THRU
.415
.2075
R.065 TYP.
4 PLCS
±.003
.220 MAX.
±.005
.040
±.002
.030 DIA.
.150 REF. 2° MAX. TYP.
±.020
.720
MEASURED
LEAD TIP
IDENT
–A–
–C–
ø
.010 B C A
M
ø
.010 C B A
2x .028
M
ø
.010 C B A
.230 MIN
.122
MAX.
.108
.300
.100
.755
.515
ESD/PIN 1
–B–
4
567
32
8
1
.632
.090
8X
Notes:
1. Dimension Tolerance: ±.005 inches
2. Package contains BeO substrate
3. Case electrically isolated
6
SCD8687 Rev B 10/24/11 Aeroflex Plainview
FIGURE 6 – VRG8688 PACKAGE OUTLINE — SURFACE MOUNT POWER PACKAGE
Notes:
1. Dimension Tolerance: ±.005 inches
2. Package contains BeO substrate
TABLE II – PIN NUMBERS vs FUNCTION
PIN FUNCTION
1ADJ_1
2VOUT_1
3 SENSE_1
4VIN_2
5ADJ_2
6VOUT_2
7 SENSE_2
8VIN_1
3. Case electrically isolated
.108
.300
.100
ø.145 THRU
.415
.2075
R.065 TYP.
4 PLCS
.755
.515
±.003
.220 MAX.
±.005
.040
±.002
.030 DIA.
.122
.150 REF.
±.020.886
IDENT
ESD/PIN 1
–B–
–A–
–C–
ø.010 B C A
M
ø.010 C B A
4
567
32
2x .028
M
ø.010 C B A
.020±.005
.060 ±.005
MAX. 8
1
.632
.090
8X
7
PLAINVIEW, NEW YORK
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Fax: 516-694-6715
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Tel: 321-951-4164
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www.aeroflex.com info-ams@aeroflex.com
Aeroflex Microelectronic Solutions reserves the right to
change at any time without notice the specifications, design,
function, or form of its products described herein. All
parameters must be validated for each customer's application
by engineering. No liab ility is assumed as a result of use of
this product. No patent licenses are implied.
EXPORT CONTROL: EXPOR T WARNING:
This product is controlled for export under the International Traffic in
Arms Regulations (ITAR). A license from the U.S. Department of
State is required prior to the export of this product from the United
States.
Aeroflex’s military and space products are controlled for export under
the International Traffic in Arms Regulations (ITAR) and may not be
sold or proposed or offered for sale to certain countries. (See ITAR
126.1 for complete information.)
SCD8687 Rev B 10/24/11
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attributes represented by these three icons:
solution-minded, perform a nce -driven and cu stom e r-foc use d
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ORDERING INFORMATION
MODEL DLA SMD # SCREENING PACKAGE
VRG8687-7 -Commercial Flow, +25°C testing only
8 Lead
Thru-Hole
Power Pkg
VRG8687-S - Military Temperature, -55°C to +125°C
Screened in accordance with the ind ividual Test Methods
of MIL-STD-883 for Space Applications
VRG8687-201-1S 5962-1021302KUC DLA SMD Pending
VRG8687-201-2S 5962-1021302KUA
VRG8688-7 - Commercial Flow, +25°C testing only
8 Lead
Surface Mount
Power Pkg
VRG8688-S - Military Temperature, -55°C to +125°C
Screened in accordance with the ind ividual Test Methods
of MIL-STD-883 for Space Applications
VRG8688-201-1S 5962-1021302KZC DLA SMD Pending
VRG8688-201-2S 5962-1021302KZA
