4096-523 January 21, 2002 Revision B Assembly Manual
2.4 METER SERIES 1254 DUAL OPTICS ANTENNA SYSTEM C-BAND
PRODELIN CORPORATION 1500 Prodelin Drive Newton NC 28658

PRODELIN CORPORATION

4096-523 2.4M SERIES 1254
2.4 Meter 2 Piece Az/El Installation Instructions

B A REV.

Revised text Revised Address Original Release

DESCRIPTION

7/14/04 1/2/02 8/27/98

CLT CLT

APPROVED
2.4M SERIES 1254 ANTENNA SYSTEM WITH DUAL OPTICS TABLE OF CONTENTS
SECTION I 1.0 1.1 1.2 1.3 1.4 1.5 1.6 TITLE GENERAL INFORMATION INTRODUCTION UNPACKING AND INSPECTION FREIGHT DAMAGE MISSING OR DAMAGED MATERIAL SUGGESTED TOOL LIST MECHANICAL ALIGNMENT TOOLS SUGGESTED MAST & FOUNDATION ANTENNA SYSTEM ASSEMBLY OVERVIEW CANISTER & AZ/EL POSITIONER INSTL REFLECTOR SUPPORT ASSEMBLY & REFLECTOR INSTALLATION FEED SUPPORT FEED SUPPORT INSTALLATION ANTENNA POINTING ALIGNMENT TO SATELLITE INITIAL ALIGNMENT MAINTENANCE MAINTENANCE OVERVIEW PERIODIC INSPECTION REFLECTOR MOUNT AND REFLECTOR SUPPORT FEED AND FEED SUPPORT

2.0 2.1 2.2

III IV
3.0 4.0 4.1 5.0 5.1 5.2 5.3 5.4
SECTION I 1.0 Introduction

GENERAL INFORMATION

This manual describes the assembly and installation of Prodelin's 2.4M 2-Piece Rx/Tx offset antenna system with an Az/El mount and Dual Optics (series number1254). The Prodelin 2.4M is a rugged, reliable antenna system that will operate at C-band frequencies with high efficiency and at the same time successfully withstand the effects of the environment. These instructions are listed by sections that cover all areas of assembly and installation. Additional sections are included in the manual to provide information on antenna alignment to the satellite and maintenance. 1.1 Unpacking And Inspection The antenna containers should be unpacked and inspected at the earliest date to ensure that all material has been received and is in good condition. A complete packing list for each major component is supplied. 1.2 Freight Damage Any damage to materials while in transit should be immediately directed to the freight carrier. He will instruct you on matters regarding any freight damage claims. 1.3 Material - Missing Or Damaged Any questions regarding missing or damaged materials that is not due to the freight carrier should be directed to Prodelin's Customer Service Department at:
1500 Prodelin Drive Newton NC 28658 (828) 464-4141
Suggested Tool List The following tools are suggested for the antenna installation. 1 ratchet 1 socket - 9/16" 1 socket - 3/4" 1 socket - 1-1/8" 1 wrench, combination - 7/wrench, combination - 1/wrench, combination - 9/16" 1 wrench, combination - 3/4" 1 wrench, combination - 15/16" 1 wrench, combination - 1-1/8" 1 wrench, combination - 1-1/2" 1 wrench, adjustable - 10" wrench (socket, crescent, or pipe) for 2 bolt
Mechanical Alignment Tools The following tools are suggested for the initial alignment to the satellite. 1) 2) 3) COMPASS INCLINOMETER TAPE RULER - 10 ft. MINIMUM
SUGGESTED MAST & FOUNDATION

6 SCH 40 PIPE (6.625 OD)

54.0 SEE NOTE #7

SECTION A-A

2 x 2 1/4 HRS ANGLE 12 INCHES LONG TYPICAL 2 PLACES
NOTES: 1. 2. 3. 4. 5. 6. 7. 8.
2 x 2 x 1/4 HRS Angle and schedule 40 pipe should conform with ASTM A36 and ASTM A53 Type E and S Grade B. All concrete should conform to building code standards and have a minimum compressive strength of 3000 PSI at 28 days. (Per ACI-318-77) Soil bearing capacity should be no less than 2000 PSF. Concrete should be poured against undisturbed soil. Allow concrete 24 hours set time before installation of antenna. The antenna should be properly grounded to meet applicable local codes. Minimum depth as shown or extend to local frost line. Foundation meets the design requirements as set forth by the uniform building code. (1982 edition)

(PRODELIN CORPORATION DOES NOT REPRESENT OR WARRANT THAT ANY PARTICULAR DESIGN OR SIZE OF FOUNDATION IS APPROPRIATE FOR ANY LOCALITY OR EARTH STATION INSTALLATION.)

SECTION II

ANTENNA ASSEMBLY
CAUTION: During the assembly procedure, the sequence of instructions must be followed. DO NOT TIGHTEN ANY HARDWARE UNTIL INSTRUCTED. 2.0 Assembly Overview The 2.4 meter dual optics antenna system consists of four (4) major components: 1) 2) 3) 4) Reflector (2 petals) Reflector Support Assembly Az/El Positioner Assembly Feed Support and Sub-reflector Assemblies
The interface from the ground foundation to the antenna is a vertical 6.63" OD pipe. It is assumed that the foundation and pipe have been properly installed. 2.1 Canister and Az/El Positioner Installation As shown in figure 2.1-1, place the canister assembly [item #1] on the mast pipe, observing the following points: Step 1: Step 2: Back out the [8] 5/8 set screws so that the canister can slip over the pipe. Snug the [8] 5/8 set screws. Loosen the 2 bolt and rotate the positioner (rectangular tube) to be at right angles to the canister plate as shown. Remove the azimuth rod from the positioner. Run one of the 1 nuts up towards the tab end of the rod; and remove the other 1 nut and one washer. Place the rod through the adjustment tube attached to the canister top plate, and replace the washer and nut. Re-attach the azimuth rod to the Az/El positioner with the 3/4-10 x 2.00 bolt, two flat washers, lock washer, nut and.80 sleeve. Tighten securely. Snug the 2 bolt at this time. The canister must be oriented correctly to the center of the satellite orbital arc. Loosen the set screws and rotate the canister on the pipe to the required position. Refer to figure 2.1-1. Tighten the set screws securely, and tighten the 5/8 lock nuts against the canister.

Step 3:

Cap bolt to be loose to attach azimuth rod. Pipe wrench or large crescent wrench. Lever bar may be used to initiate movement.
TO CENTER OF SATELLITE ORBITAL ARC (WITHIN 5)
90 (CENTER OF AZIMUTH ADJUSTMENT RANGE)
Loosen hardware to slide over mast pipe. (Snug only until nominal position is found)

FIGURE 2.1-1

Figure indicates assembled rod. Hardware must be removed first to fix in position shown. Rod is not attached to facilitate packaging. POSITIONER INSTALLATION TABLE 2.1-1

ITEM # 1

PART # 0181-691
PARTS LIST DESCRIPTION 2.4M 2Pc Az/El Positioner Assy 9

Reflector Support Assembly & Reflector Installation The reflector support assembly consists of a 2 Piece reflector support tube and three reflector crossarms which provide the necessary structural support and alignment positions on which the reflector petals are mounted. The reflector petals are labeled A and B with A being the left side when viewed from behind and B being the right side. In the standard upright position (feed support at bottom), the antennas elevation range is 5 to 90.

Step 1:

Place three of the threaded inserts (item 3) through the face of each reflector petal (item 1 & 2) and secure with 3/4 flat washer, lock washer, and hex nut. (items 8,9, & 10). Snug, but do not completely tighten at this time. See figure 2.2-1.
Figure 2.2-1 Step 2:Remove the 1 diameter bolt from the elevation axis of the Az/El positioner and place the reflector support tube (item #4) on the positioner as shown in figure 2.2-2. Replace the 1 bolt and tighten snug only. Let the tube lie down on the positioner.
Step 3:Attach the top & bottom crossarms (items 5) to the reflector support tube with a 1/x 2.50 bolt, [2] flat washers, lock washers, and hex nut (items 11,12,13, & 14) in each of four locations as shown in figure 2.2-2. Do not tighten. Step 4:Place one reflector petal onto the crossarms in the upright position (see figure 2.2-3) and attach with a 3/8 - 16 x 1.25 bolt, flat washer, and lock washer (items 18, 19, & 20) at each crossarm. Do not tighten. Step 5:Place the second reflector petal onto the crossarms and attach as in step #4. Step 6:Insert steel template between reflector petals then attach the two petals together with 1/2-13 x 1.25 bolts, two narrow flat washers, lock washer, and hex nut (item 16, 17, 13, & 14) in the 9 locations as shown in figure 2.2-4. Tighten these bolts securely at this time while aligning the petals at the face of reflector. Step 7:Carefully swing the reflector up into a vertical position. Remove the bottom 1 hex nut and flat washer from the elevation adjustment assembly (item 6) and insert the assembly through the elevation adjustment tube at the back of the Az/El positioner as shown in figure 2.2-5. Replace the flat washer and hex nut. Step 8:Remove the 3/4 hardware and sleeve from the end of the elevation assembly and attach to the reflector support tube. Tighten securely. Step 9:Attach the center crossarm (item 7) to the reflector support tube with a 1/2-13 x 5.00 bolt, two flat washers, lock washer, and hex nut (item 15,12,13, & 14) in each of the two locations as shown in figure 2.2-6. Step 10: Attach the center crossarm to the reflector petals at the two(2) threaded inserts (item 3) with 3/8 - 16 x 4.00 bolt, flat washer, and lock washer (item 18, 19, & 20). Tighten the reflector support hardware by first tightening the 3/4 hardware at the six reflector inserts followed by the 3/8 bolts holding the reflector to the three crossarms. Next tighten the [6] 1/2 bolts holding the three crossarms to the reflector support tube. Do not tighten the elevation hardware until after satellite alignment.

Step 11:

2.4 METER AZ/EL PARTS LIST ITEM 21 PART NO. 0179-381 0179-383 0179-382 0179-384 0159-283 0490-676 0250-696 0181-249 0490-633 8201-045 8200-015 8106-007 8033-021 8201-043 8202-043 8104-007 8033-040 8033-010 8201-030 8032-010 8201-042 8202-042 8032-032 DESCRIPTION Reflector A Side Reflector A Side w/SHC Reflector B Side Reflector B Side w/SHC Threaded insert Reflector Support Tube Top and Bottom Crossarm Elevation Adjustment assembly Center Crossarm 3/4 Flat washer 3/4 Lock washer 3/4 Nut 1/2-13 x 2.50 bolt 1/2 Flat washer - wide 1/2 Lock washer 1/2 Nut 1/2-13 x 5.00 bolt 1/2-13 x 1.25 bolt 1/2 Flat washer - narrow 3/8-16 x 1.25 bolt 3/8 Flat washer 3/8 Lock washer 3/8-16 x 4.00 bolt QTY 2

Figure 2.2-2

Figure 2.2-3

Figure 2.2-4

Figure 2.2-5 16

Figure 2.2-6

SECTION III

FEED SUPPORT ASSEMBLY

The following instructions are for installing a C-band dual optics feed support to Prodelin's 2.4 meter antenna system. 3.0 Feed Support Installation 1. Attach feed support extension (item #16) to reflector support tube using (6)1/2-13 x 1.50 bolts, flat washers, lock washers. Center extension with reflector major axis while tightening. Reference Figure 3.0-0 2. Attach the longer flat end of the feed rods loosely to the outside of the crossarm with 5/16-18 x 1.50" bolts, flat washers, lock washers and nuts. Reference Figure 3.0-1. Lift the end of the feed support tube and attach to the bottom of the feed extension with a 1-8 x 6.00 bolt, flatwashers, lockwasher, and hex nut. Reference Figure 3.0-2. Position Sub-reflector cradle assembly at end of feed support tube (sub-reflector facing main reflector) and secure using (2) 3/8-16 x 5.00 bolts, flat washers, lock washers and nuts. Secure the unattached ends of the feed rods on to the sides of the feed support tube using a 3/8-16 x 5.00 bolt, flat washers, lock washer, and hex nut as shown in Figure 3.0-3.

FEED SUPPORT PARTS LIST

ITEM 15 PART NO. 0250-695 0176-279 8031-012 8032-040 8036-048 8201-041 8201-042 8201-046 8202-041 8202-042 8202-046 8101-009 8102-007 8107-007 0490-632 Feed Support Feed Rod 5/16-18 x 1.50 bolt 3/8-16 x 5.00 bolt 1-8 x 6.00 bolt 5/16 Flat Washer 3/8 Flat Washer 1 Flat Washer 5/16 Lock Washer 3/8 Lock Washer 1 Lock Washer 5/16-18 Hex Nut 3/8-16 Hex Nut 1-8 Hex Nut Weldment, Feed Extension DESCRIPTION QTY 1

C-BAND DUAL OPTICS FEED ROD MOUNTING

SECTION IV 4.0

ANTENNA POINTING
Alignment To Satellite The 2.4M offset reflector contains a 22.3 elevation offset angle. Therefore, when the reflector aperture is perpendicular to the ground, the antenna is actually looking 22.3 in elevation. The following alignment procedure is intended only as a general reference guide for this antenna. For proper antenna performance, accurate alignment is critical. Therefore, it is recommended that your own detailed procedure be used or contact Prodelins Technical Support Department for additional recommendations.
Initial Alignment 1) 2) Place an inclinometer on the reflector support as shown in figure 4.1-1. Remember to add 22.3 to the reading to allow for the reflector's offset angle. Raise or lower the antenna to find the desired elevation by turning the 1" nuts located at the elevation block. Position the top nut so that it will not interfere with adjustment. Turn the bottom nut clockwise to increase elevation and counterclockwise to decrease elevation. After the correct elevation angle is set, rotate the antenna in azimuth by loosening the 1 nuts on the azimuth adjustment rod. Rotate azimuth until a signal is reached. Peak the antenna signal by fine adjustments made in both azimuth and elevation. Tighten all of the hardware used for adjustments. Tighten 2 bolt.

4) 5) 6)

Figure 4.1-1

SECTION V 5.0

MAINTENANCE
Maintenance Overview After installation, the antenna requires only periodic inspection. It is anticipated that maintenance, if required, will be minimal and easily handled by a local or in-house maintenance staff. The materials used in the construction of this Earth Station Antenna virtually eliminate any maintenance repairs.
Periodic Inspection It is suggested that a periodic inspection be performed at least every six months. NOTE: After any very severe weather conditions, inspection of the antenna should be performed to determine if foreign objects have caused damage or if survival specifications have been exceeded. This inspection should include the following: 1) 2) 3) 4) Check all bolting locations - all bolts should be tight. Check all structural members - repair or replace if damaged. Check the foundation anchor bolts - they must be secure and with no failure signs in foundation. Check for corrosion - on the reflector structure and mount.
Reflector Prodelin's reflector does not require any maintenance. The composite construction of the reflector is virtually impervious to any damages that could be caused by weather or other atmospheric conditions. It is only necessary to inspect for any physical damage done by vandalism or very severe weather conditions. Should any damage be detected to a portion of the reflector, contact the Customer Service Department at Prodelin for recommendations involving reflector repair. 23
Mount And Reflector Support Structure The mount and reflector support structure supplied with this antenna is of steel construction and has a hot-dipped galvanized finish. If inspection shows any signs of structural failure, the mount members that are damaged should be repaired or replaced. Corrosion: Any corrosion on steel members may be repaired with a cold, zinc-rich galvanizing paint.

Feed And Feed Support The feed support system should be inspected to insure that all hardware is secure. The feed/radio mounting bolts should be tight. The feed horn window should be inspected to insure that it is intact so that no moisture can collect inside the feed horn. Replace if damaged.

LT1253/LT1254 Low Cost Dual and Quad Video Amplifiers

FEATURES

s s s s s s s s

DESCRIPTIO

Low Cost Current Feedback Amplifiers Differential Gain: 0.03%, RL = 150, VS = 5V Differential Phase: 0.28, RL = 150, VS = 5V Flat to 30MHz, 0.1dB 90MHz Bandwidth on 5V Wide Supply Range: 2V(4V) to 14V(28V) Low Power: 60mW per Amplifier at 5V
The LT1253 is a low cost dual current feedback amplifier for video applications. The LT1254 is a quad version of the LT1253. The amplifiers are completely isolated except for the power supply pins and therefore have excellent isolation, over 94dB at 5MHz. Dual and quad amplifiers significantly reduce costs compared with singles; the number of insertions is reduced and fewer supply bypass capacitors are required. In addition, these duals and quads cost less per amplifier than single video amplifiers. The LT1253/LT1254 amplifiers are ideal for driving low impedance loads such as cables and filters. The wide bandwidth and high slew rate of these amplifiers make driving RGB signals between PCs and workstations easy. The excellent linearity of these amplifiers makes them ideal for composite video. The LT1253 is available in 8-pin DIPs and the S8 surface mount package. The LT1254 is available in 14-pin DIPs and the S14 surface mount package. Both parts have the industry standard dual and quad op amp pin out. For higher performance, see the LT1229/LT1230.

APPLICATI

RGB Cable Drivers Composite Video Cable Drivers Gain Blocks in IF Stages

TYPICAL APPLICATI

5V VIN +

Transient Response

75 1/2 LT1253 5V RF 620 VOUT RG 75 CABLE

AV = 1 +

RF BW = 90MHz RG AT AMPLIFIER OUTPUT. 6dB LESS AT VOUT.

LT1253/54 TA01

VS = 5V AV = 2 RL = 150 VO = 1V

LT1253/54 TA02

LT1253/LT1254 ABSOLUTE AXI U RATI GS
Storage Temperature Range. 65C to 150C Junction Temperature (Note 2).. 150C Lead Temperature (Soldering, 10 sec).. 300C Total Supply Voltage (V + to V ).. 28V Input Current... 15mA Output Short-Circuit Duration (Note 1). Continuous Operating Temperature Range LT1253C, LT1254C.. 0C to 70C

PACKAGE/ORDER I FOR ATIO

TOP VIEW OUT A IN A +IN A V A B IN B +IN B V+ OUT B
ORDER PART NUMBER LT1253CN8 LT1253CS8 S8 PART MARKING 1253
N8 PACKAGE 8-LEAD PLASTIC DIP
S8 PACKAGE 8-LEAD PLASTIC SOIC
TJMAX = 150C, JA = 100C/ W (N) TJMAX = 150C, JA = 150C/ W (S)
ELECTRICAL CHARACTERISTICS
Symbol VOS +IB IB AVOL PSRR CMRR VOUT IOUT IS RIN CIN Parameter Input Offset Voltage Noninverting Bias Current Inverting Bias Current Large-Signal Voltage Gain Power Supply Rejection Ratio Common-Mode Rejection Ratio Maximum Output Voltage Swing Maximum Output Current Supply Current Input Resistance Input Capacitance Power Supply Range Channel Separation SR Input Slew Rate Output Slew Rate Dual Single
0C TA 70C, VS = 5V to 12V, unless otherwise noted.
MIN TYP 20 MAX 100 UNITS mV A A V/V dB dB V V mA 11 mA M pF 250 V V dB V/s V/s

CONDITIONS

VS = 5V, VO = 2V, RL = 150 VS = 3V to 12V VS = 5V, VCM = 2V VS = 12V, RL = 500 VS = 5V, RL = 150 Per Amplifier

f = 10MHz AV = 1 AV = 2

TOP VIEW

7 B C A D

14 OUT D 13 IN D 12 +IN D 11 V 10 +IN C 9 8
ORDER PART NUMBER LT1254CN LT1254CS

IN A +IN A V+ +IN B IN B

N PACKAGE 14-LEAD PLASTIC DIP
S PACKAGE 14-LEAD PLASTIC SOIC
TJMAX = 150C, JA = 70C/ W (N) TJMAX = 150C, JA = 100C/ W (S)

55 7.0 2.4

65 10.5 3.3

LT1253/LT1254

Symbol tr tp Parameter Small-Signal Rise Time Rise and Fall Time Propagation Delay
MIN TYP 3.5 5.8 3.5 MAX UNITS ns ns ns
CONDITIONS VS = 12V, AV = 2 VS = 5V, AV = 2, VOUT = 1VP-P VS = 5V, AV = 2
Note 1: A heat sink may be required to keep the junction temperature below absolute maximum when the output is shorted indefinitely. Note 2: TJ is calculated from the ambient temperature TA and power dissipation PD according to the following formulas:
LT1253CN8: TJ = TA + (PD 100C/W) LT1253CS8: TJ = TA + (PD 150C/W) LT1254CN: TJ = TA + (PD 70C/W) LT1254CS: TJ = TA + (PD 100C/W)

TYPICAL AC PERFOR A CE

BANDWIDTH
VS AV RL RF RG None None 68.1 68.1 None None 61.9 61.9 Small Signal 3dB BW (MHz) Small Signal 0.1dB BW (MHz) Small Signal Peaking (dB) 3.4 1.3 0.1 0.1 0.0.1 0.1 1.5 0.1 0.1 0.1 0.1 0.0

NTSC VIDEO (Note 1)

VS AV RL RF RG DIFFERENTIAL GAIN 0.01% 0.01% 0.03% 0.03% DIFFERENTIAL PHASE 0.03 0.12 0.18 0.28
Note 1: Differential Gain and Phase are measured using a Tektronix TSG 120 YC/NTSC signal generator and a Tektronix 1780R Video Measurement Set. The resolution of this equipment is 0.1% and 0.1. Ten identical
amplifier stages were cascaded giving an effective resolution of 0.01% and 0.01.

TYPICAL PERFOR A CE CHARACTERISTICS
Supply Current vs Supply Voltage
OUTPUT SATURATION VOLTAGE (V)

V+ 0.5

SUPPLY CURRENT (mA)

55C 25C 125C

COMMON-MODE RANGE (V)

SUPPLY VOLTAGE (V) 175C

LT1253/54 TPC01
Settling Time to 10mV vs Output Step

DISTORTION (dBc)

NONINVERTING

INVERTING

POWER SUPPLY REJECTION (dB)

OUTPUT STEP (V)

SETTLING TIME (ns) NONINVERTING INVERTING VS = 12V RF = RG = 1k

LT1253/54 TPC04

Spot Noise Voltage and Current vs Frequency

OUTPUT IMPEDANCE ()

OUTPUT SHORT-CIRCUIT CURRENT (mA)
SPOT NOISE (nV/Hz OR pA/Hz)

en +in 1 10

1k 10k FREQUENCY (Hz)

LT1253/54 TPC07

Output Saturation Voltage vs Temperature

V+ 0.5 1.0 1.5 2.0

Input Common-Mode Limit vs Temperature

1.0 RL = 2V VS 12V

V + = 2V TO 12V
2.0 1.5 1.0 0.5 V V = 2V TO 12V

1.0 0.5 V 50 25

TEMPERATURE (C)

LT1253/54 TPC02

LT1253/54 TPC03
2nd and 3rd Harmonic Distortion vs Frequency
20 VS = 12V VO = 2VP-P RL = 100 RF = 750 AV = 10dB
Power Supply Rejection vs Frequency
80 VS = 12V RL = 100 RF = RG = 750 POSITIVE 40

40 3RD 50

NEGATIVE 20

10 FREQUENCY (MHz) 100

LT1253/54 TPC05

1M 10M FREQUENCY (Hz)

LT1253/54 TPC06
Output Impedance vs Frequency

100 VS = 12V

Output Short-Circuit Current vs Temperature
1.0 RF = RG = 2k 0.1 RF = RG = 750

0.001 10k

175 TEMPERATURE (C)

LT1253/54 TPC09

LT1253/54 TPC08

12V Frequency Response

PHASE 40 60

GAIN (dB)

1M VS = 12V AV = 1 RL = 150 RF = 1k 10M 100M FREQUENCY (Hz)
2 1M VS = 12V AV = 2 RL = 150 RF = 715 RG = 715 GAIN

10M 100M FREQUENCY (Hz)

1M VS = 12V AV = 10 RL = 150 RF = 620 RG = 68.1 GAIN

5V Frequency Response

PHASE (DEG)

40 PHASE 60

200 1G

LT1253/54 TPC10

5 1M VS = 5V AV = 1 RL = 150 RF = 787 10M 100M FREQUENCY (Hz) 1G

LT1253/54 TPC11

GAIN 200

LT1253/54 TPC12

2 1M VS = 5V AV = 2 RL = 150 RF = 620 RG = 620 GAIN
200 10M 100M FREQUENCY (Hz) 1G

LT1253/54 TPC13

LT1253/54 TPC14
16 1M VS = 5V AV = 10 RL = 150 RF = 562 RG = 61.9 GAIN

LT1253/54 TPC15

Transient Response Transient Response

VS = 5V AV = 1 RL = 150

RF = 787 VO = 1V

APPLICATIO S I FOR ATIO

Power Dissipation
The LT1253/LT1254 amplifiers combine high speed and large output current drive into very small packages. Because these amplifiers work over a very wide supply range, it is possible to exceed the maximum junction temperature under certain conditions. To insure that the LT1253/ LT1254 are used properly, we must calculate the worst case power dissipation, define the maximum ambient temperature, select the appropriate package and then calculate the maximum junction temperature. The worst case amplifier power dissipation is the total of the quiescent current times the total power supply voltage plus the power in the IC due to the load. The quiescent supply current of the LT1253/LT1254 has a strong negative temperature coefficient. The supply current of each amplifier at 150C is less than 7mA and typically is only 4.5mA. The power in the IC due to the load is a function of the output voltage, the supply voltage and load resistance. The worst case occurs when the output voltage is at half supply, if it can go that far, or its maximum value if it cannot reach half supply. For example, lets calculate the worst case power dissipation in a video cable driver operating on a 12V supply that delivers a maximum of 2V into 150.

LT1253/54 TPC16

RF = 562 RG = 61.9 VO = 1.5V

VS = 5V AV = 10 RL = 150

LT1253/54 TPC17
PDMAX = 2 VS ISMAX + (VS VOMAX) VOMAX/RL PDMAX = 2 12V 7mA + (12V 2V) 2V/150 = 0.168 + 0.133 = 0.301 Watt per Amp Now if that is the dual LT1253, the total power in the package is twice that, or 0.602W. We now must calculate how much the die temperature will rise above the ambient. The total power dissipation times the thermal resistance of the package gives the amount of temperature rise. For the above example, if we use the S8 surface mount package, the thermal resistance is 150C/W junction to ambient in still air. Temperature Rise = PDMAX RJA = 0.602W 150C/W = 90.3C The maximum junction temperature allowed in the plastic package is 150C. Therefore the maximum ambient allowed is the maximum junction temperature less the temperature rise. Maximum Ambient = 150C 90.3C = 59.7C Note that this is less than the maximum of 70C that is specified in the absolute maximum data listing. In order to use this package at the maximum ambient we must lower the supply voltage or reduce the output swing.
As a guideline to help in the selection of the LT1253/ LT1254, the following table describes the maximum supply voltage that can be used with each part based on the following assumptions: 1. The maximum ambient is 70C. 2. The load is a double-terminated video cable, 150. 3. The maximum output voltage is 2V (peak or DC).

SI PLIFIED SCHE ATIC

One Amplifier

PACKAGE DESCRIPTIO

Dimensions in inches (millimeters) unless otherwise noted.
0.300 0.320 (7.620 8.128)

0.045 0.065 (1.143 1.651)
0.009 0.015 (0.229 0.381)
0.065 (1.651) TYP 0.125 (3.175) MIN 0.020 (0.508) MIN
+0.025 0.325 0.015 +0.635 8.255 0.381
0.045 0.015 (1.143 0.381) 0.100 0.010 (2.540 0.254)
Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
MAX POWER at MAX TA LT1253CN8 LT1253CS8 LT1254CN LT1254CS VS < 14 (Abs Max) VS < 10.6 VS < 11.4 VS < 7.6 0.800W 0.533W 1.143W 0.727W

IN VOUT V

LT1253/54 SS
N8 Package 8-Lead Plastic DIP

0.400 (10.160) MAX 6 5

0.130 0.005 (3.302 0.127)
0.250 0.010 (6.350 0.254)
0.018 0.003 (0.457 0.076)

N8 0392

PACKAGE DESCRIPTIO U
Dimensions in inches (millimeters) unless otherwise noted. N Package 14-Lead Plastic DIP
0.065 (1.651) TYP 12 0.770 (19.558) MAX 9 8
0.300 0.325 (7.620 8.255)
0.015 (0.380) MIN 0.130 0.005 (3.302 0.127)
0.009 0.015 (0.229 0.381) +0.025 0.325 0.015 +0.635 8.255 0.381
0.260 0.010 (6.604 0.254)
0.075 0.015 (1.905 0.381)
0.018 0.003 (0.457 0.076) 0.100 0.010 (2.540 0.254)

1 0.125 (3.175) MIN

N14 0392

S8 Package 8-Lead SOIC

0.189 0.197 (4.801 5.004) 0.010 0.(0.254 0.508) 0.008 0.010 (0.203 0.254) 0.016 0.050 0.406 1.270 0.053 0.069 (1.346 1.752) 0.004 0.010 (0.101 0.254) 0.228 0.244 (5.791 6.197) 0.150 0.157 (3.810 3.988) 6 5
0.014 0.019 (0.355 0.483)

0.050 (1.270) BSC

SO8 0392

S Package 14-Lead SOIC

0.337 0.344 (8.560 8.738) 0.010 0.(0.254 0.508) 0.008 0.010 (0.203 0.254) 0.053 0.069 (1.346 1.752) 0.004 0.010 (0.101 0.254) 0.228 0.244 (5.791 6.197) 0.150 0.157 (3.810 3.988) 8

0.016 0.050 0.406 1.270

0.050 (1.270) TYP

SO14 0392

Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7487
(408) 432-1900 q FAX: (408) 434-0507 q TELEX: 499-3977

LT/GP 0193 10K REV 0

LINEAR TECHNOLOGY CORPORATION 1993