View DSC-10510-444S_635246.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

DSC-10510
7 VA DIGITAL-TO-SYNCHRO CONVERTER
DESCRIPTION
With 16-bit resolution and up to 2 minute accuracy, the DSC-10510 M is a high power digital-to-synchro converter capable of driving multiple Control Transformer (CT), Control Differential Transmitter (CDX) and Torque Receiver (TR) loads up to 7 VA. The DSC-10510 contains a high accuracy D/R converter, a triple power amplifier stage, a walkaround circuit (to prevent torque receiver hangups), and thermal and over-current protection circuits. The hybrid is protected against overloads, load transients, over-temperature, loss of reference, and power amplifier or DC power supply shutdown. Microprocessor compatibility is provided through a 16-bit/2-byte doublebuffered input latch. Data input is natural binary angle in TTL compatible parallel positive logic format. Packaged in a 40-pin TDIP, the DSC10510 features a power stage that may be driven by either a standard 15 VDC supply or by a pulsating reference supply when used with an optional power transformer. When powered by the reference source, heat dissipation is reduced by 50%.
FEATURES
* 7 VA Drive Capability for CT,
CDX, or TR Loads
* Double Buffered Transparent
Input Latch
* 16-Bit Resolution * Up to 2 Minute Accuracy * Power Amplifier Uses
Pulsating or DC Supplies
APPLICATIONS
The DSC-10510 can be used where digitized shaft angle data must be converted to an analog format for driving CTs, CDXs, and TRs loads. With its double buffered input latches, the DSC-10510 easily interfaces with microprocessor based systems such as flight simulators, flight instrumentation, fire control systems, and flight data computers.
* Built-In-Test (BIT) Output
R 36 RH 26 V REF RL 18 100k 17 RH' 3.4 V REF RL' 13k 35 13k 34 + -R 100k
+15 VDC 30
-15 VDC 29 SIN
+V OR +15 V 23
-V OR -15 V 24
REMOTE SENSE 19 S1' 20 S1 S1
D/R CONVERTER HIGH ACCURACY LOW SCALE FACTOR VARIATION
COS
ELECTRONIC SCOTT-T & TRIPLE POWER AMPLIFIER
25 S2' 21 S2 26 S3' 22 S3 S3 S2
DELAY OVER-CURRENT WALK AROUND CIRCUIT
POWER STAGE ENABLE 15 VDC -R THERMAL SENSE 140 CASE
39
BIT
TRANSPARENT LATCH TRANSPARENT LATCH 28 31 LA 33 LM 1-8 BITS 1-8 9-16 32 BITS 9-16 LL
15 VDC -R 37 40 K EN
38 BS
FIGURE 1. DSC-10510 BLOCK DIAGRAM (c) 1986, 1999 Data Device Corporation
M DDC Custom Monolithics utilized in this product are copyright under the Semiconductor Chip Protection Act.
PARAMETER RESOLUTION ACCURACY
TABLE 1. DSC-10510 SPECIFICATIONS VALUE DESCRIPTION 16 bits 2 or 4 minutes 1 LSB max in the 16th bit 40 s max For any digital input step change (passive loads). TTL/CMOS compatible All inputs except K (Kick pin 40). Bits 1-16, BS, and EN. LL, LM, and LA (CMOS transient protected) Ground to enable Kick circuit, open to disable; pulls self up to +15 V. Logic 0 for BIT condition (see BIT pin function) Logic 0 = 1 TTL Load Logic 1 = 10 TTL Loads 1.6 mA at 0.4 V max 0.4 mA at 2.8 V min Bit 1 = MSB, Bit 16 = LSB
TABLE 1. DSC-10510 SPECIFICATIONS (contd) PARAMETER SYNCHRO OUTPUT Voltage L-L Scale Factor Variation Current CT, CDX or TR Load DC Offset Protection VALUE DESCRIPTION
DIFFERENTIAL LINEARITY OUTPUT SETTLING TIME
11.8 Vrms 0.5% for nom Ref V 0.1% max
Simultaneous amplitude variation on all output lines as a function of digital angle.
DIGITAL INPUT/ OUTPUT Logic Type Digital Inputs Logic 0 = 0.8 V max Logic 1 = 2.0 V min Loading 20 A max to GND //5pf max 20 A max to + 5V //5 pf max K 20 A max
700 mA rms max 7 VA max 15 mV max Each line to ground. Varies with angle. Output protected from overcurrent, voltage feedback transient, and over temperature, loss of reference, loss of power amplifier, and loss of DC supply voltage.
Digital Outputs BIT
Drive Capability
REFERENCE INPUT Type 26 Vrms differential 3.4 Vrms differential Max Voltage w/o Damage 72.8 Vrms for RH-RL 9.52 Vrms for RH'-RL' Frequency DC to 1 kHz Input Impedance Single Ended 100k Ohms 0.5% 13k Ohms 0.5% Differential 200k Ohms 0.5% 26k Ohms 0.5%
RH-RL RH' -RL'
RH-RL RH'-RL' RH-RL RH'-RL'
POWER SUPPLY CHARACTERISTICS Nominal Voltage 15 V V Voltage Range 5%, 20 V peak max 3 V above output min Max Voltage w/o Damage 18 V 25 V Current 25 mA load dependent max TEMPERATURE RANGES Operating Case -3XX 0C to +70C -1XX -55C to +125C Storage -65C to +150C PHYSICAL CHARACTERISTICS Size 2.0 x 1.1 x 0.2 inches 40 Pin Triple DIP (50.8 x 27.9 x 5.1 mm) Weight 0.9 oz (25.5 g)
INTRODUCTION
SYSTEM CONSIDERATIONS:
Power Surge at Turn On When power is initially applied, the output power stages can go on fully before all the supplies stabilize. When multiple D/S converters with substantial loads are present, the heavy load can cause the system power supply to have difficulty coming up and indeed may even shut down. It is best to be sure that the power can handle the turn-on surge or to stagger the D/S turn-ons so that the supply can handle it. Typically, the surge will be twice the max rated draw of the converter. Torque Load Management When multiple torque loads (TR) are being driven the above problems are exacerbated by the high power levels involved and power supply fold back problems are common unless the stagger technique is used. Also, allow time for the load to stabilize. On turn-on it is not likely that all the output loads will be at the same angle as the D/S output. As the angular difference increases so does the power draw until the difference is 180
degrees. At this point the load impedance drops to Zss and current draw is at maximum. Pulsating Power Supplies D/S and D/R converters have been designed to operate their output power stages with pulsating power to reduce power dissipation and power demand from regulated supplies. FIGURES 2 and 3 illustrate this technique. Essentially the power output stage is only supplied with enough instantaneous voltage to be able to drive the required instantaneous signal level. Since the output signal is required to be in phase with the AC reference, the AC reference can be full wave rectified and applied to the push-pull output drivers. The supply voltage will then be just a few volts more than the signal being output and internal power dissipation is minimized. Thermal Considerations Power dissipation in D/S and D/R circuits are dependent on the load, whether active (TR) or passive (CT or CDX) and the power supply, whether DC or pulsating. With inductive loads we must bear in mind that virtually all the power consumed will
2
have to be dissipated in the output amplifiers. This sometimes requires considerable care in heat sinking.
Example:
For illustrative purposes let us make some thermal calculations using the DSC-10510's specifications. The DSC-10510 has a 7 VA drive capability for CT, CDX, or TR loads. Let us take the simplest case first: Passive Inductive Load and 15 Volt DC power stage supplies (as shown in FIGURE 2). The power dissipated in the power stage can be calculated by taking the integral of the instantaneous current multiplied by the voltage difference from the DC supply that supplies the current and instantaneous output voltage over one cycle of the reference. For an inductive load this is a rather tedious calculation. Instead let us take the difference between the power input from the DC supplies minus the power delivered to the load. A real synchro load is highly inductive with a Q of 4-6; therefore, let's assume that it is purely reactive. The power out, then, is 0 Watts. As a worst case we will also assume the load is the full 7 VA, the converter's rated load. The VA delivered to the load is independent of the angle but the voltage across the synchro varies with the angle from a high of 11.8 Volts line-to-line (L-L) to a low of 10.2 V L-L. The maximum current therefore is 7VA/10.2 V = 0.68 A rms. The output is L-L push-pull, that is, all the current flows from the positive supply out to the load and back to the negative supply. The power input is the DC voltage times the average current or 30 V x (0.68 A x 0.635/0.707) [avg/rms] = 18.32 Watts. The power dissipated by the output driver stage is over 18 Watts shared by the six power transistors. Since one synchro line supplies all the current while the other two share it equally, one will dissipate 2/3 of the power and other two will each dissipate 1/3. There are 2 transistors per power stage so each of the two transistors dissipates 1/3 of the power and the other transistors dissipate 1/6 of the power. This results in a maximum power in any one transistor of 1/3 x 18.32 W = 6.04 Watts. The heat rise from the junction to the outside of the package, assuming a thermal impedance of 4C per watt = 24.16C. At an operating case temperature of 125C the maximum junction temperature will be 149.16C.
The other extreme condition to consider is when the output voltage is 11.8. The current then will be 0.42 A and the power will be 30 x (0.42A x 0.635/0.707) = 11.32 Watts. A similar calculation will show the maximum power per transistor to be 2.3 Watts. Much less than the other extreme. For Pulsating Supplies, the analysis is much more difficult. Theoretical calculations, for a purely reactive load with DC supplies equal to the output voltage peak vs. pulsating supplies with a supply voltage equal to the output voltage yield an exact halving of the power dissipated. At light loads the pulsating supplies approximate DC supplies and at heavy loads, which is the worst case, they approximate a pulsating supply as shown in FIGURE 4. Advantages of the pulsating supply technique are: * Reduced load on the regulated 15 VDC supplies * Halving of the total power * Simplified power dissipation management
ACTIVE LOAD
Active load - that is torque receivers - make it more difficult to calculate power dissipation. The load is composed of an active part and a passive part. FIGURE 5 illustrates the equivalent two wire circuit. At null that is when torque receiver's shaft rotates to the angle that minimizes the current in R2, the power dissipated is at its lowest. The typical ratio of Zso/Zss = 4.3. For the maximum specified load of Zss = 2 ohm, the Zso = 2 x 4.3 = 8.6 ohms. Also, the typical ratio of R2/R1= 2. In a synchro systems with a torque transmitter driving a torque receiver, the actual line impedances are as shown in FIGURE 6. The torque transmitter and torque receiver are electrically identical, hence the total line impedance is double that of FIGURE 5. The torque system is designed to operate that way. The higher the total line impedances, the lower the current flow at null and the lower the power dissipation. It is recommended that with torque loads, discrete resistors be used as shown in FIGURES 7 and 8. A torque load is usually at null. Once the torque receiver nulls at power turn on, the digital commands to the D/S are usually in
6 3.4V rms 7 3 4 21.6V rms C.T. + C1 + D4 D3 C2 -V GND
1 REFERENCE SOURCE 26V rms 400Hz 2 T1 42359
+v
RL' +V D2 RH' S1' S1 S2' S2 S3' S3 S1
+DC SUPPLY LEVEL POSITIVE PULSATING SUPPLY VOLTAGE AMPLIFIER OUTPUT VOLTAGE ENVELOPE
D1 5
S2 S3
DSC10510
NEGATIVE PULSATING SUPPLY VOLTAGE
DIGITAL INPUT NOTES: PARTS LIST FOR 400Hz D1, D2, D3, D4 = 1N4245 C1 AND C2 = 47F, 35V DC CAPACITOR
15VDC
-v
-DC SUPPLY LEVEL
FIGURE 2. TYPICAL CONNECTION DIAGRAM UTILIZING PULSATING POWER SOURCE
3
FIGURE 3. PULSATING POWER SUPPLY VOLTAGE WAVEFORMS
smaller angular steps, so the torque system is always at or near null. Large digital steps, load disturbances, a stuck torque receiver or one synchro line open, however, causes an off null condition. Theoretically, at null the load current could be zero (See FIGURE 9 ). If Vac = Vab, both in magnitude and phase, then, when "a" was connected to "b," no current would flow. Pick C1 and C2 to match the phase lead of R1 - Zso. In practice this ideal situation is not realized. The input to output transformation ratio of torque receivers are specified at 2% and the turns ratio at 0.4%. The inphase current flow due to this nominal output voltage (10.2 V) multiplied by the % error (2.4/100) divided by total resistance (4 Ohms) = 61mA. A phase lead mismatch between the torque receiver and the converter of 1 degree results in a quadrature current of 10.2 V x sin 1/4 Ohms = 44.5 mA. Total current is the phaser sum 61 + 44.5 = 75.5 mA . Power dissipation is 30 VDC x 75.5 mA rms x 0.9 (avg/rms) = 2.04 Watts. Since this is a light load condition, even pulsating supplies would be approximating DC supplies. The off null condition power dissipation is quite different. Real synchros have no current limiting, so that the circuit current would be the current that the circuit conditions demanded. The worst case would be for a 180 degree error between the two synchros as shown in FIGURE 10. For this condition the two equivalent voltage sources would be 10.2 V opposing. The current would be (10.2 x 2) / 4 = 5.1 A in phase. The power dissipated in the converter is the power supplied by the 15 VDC supplies minus the power delivered to the load. (30 V x 5.1 A x 0.9) - (10.2 V x 5.1 A) = 87.7 Watts for DC supplies. This would require a large power supply and high wattage resistors. The converter output current is usually limited (in the DSC-10510 case to 0.8 A peak). This limits the power supply to more rea-
sonable values but introduces another problem - the torque receiver can hang up in a continuous current limited condition at a false stable null. Fortunately, the DSC-10510 has special circuits that sense this continuous current overload condition and sends a momentary 45 "kick" to the torque receiver thus knocking it off the false null. The torque receiver will then swing to the correct angle and properly null. If the torque receiver is stuck it will, not be able to swing off the over-current condition. In this case the converter will send a BIT signal when the case exceeds 140C. This BIT signal can be used to shut down the output power stage. An additional advantage of using pulsating power supplies is that the loss of reference when driving torque loads is fail safe. The load will pump up the V voltage through the power stage clamp diodes and the loss of the reference detector will disable the power stage. The power stage will, therefore, be turned off with the needed power supply voltages. The pulsating power supply diodes will isolate the pumped up pulsating supplies from the reference. If the DC power supplies are to be used for the power stage and there is a possibility of the DC supplies being off while the reference to the torque receiver is on, then the protection circuitry shown in FIGURE 11 is highly recommended. A remote sense feature is incorporated in DDC's DSC-10510 hybrid digital-to-synchro converter. Rated at 7 VA, it offers accuracies to 2 minutes of arc at the load. This remote sense feature operates just as other precision sources do. A separate line is run to each leg of the synchro (in addition to the drive line) to sense the voltage actually appearing on the load. This is then used to regulate the output based on load voltage rather than converter output voltage. This feature is very useful in driving heavy passive loads in precision systems.
+15VDC LIGHT LOAD HEAVY LOAD
REF
R1
R2
R2
R1
REF
-15VDC
TORQUE TRANSMITTER
TORQUE RECEIVER
FIGURE 4. LOADED WAVEFORMS
3-WIRE SYNCHRO R2=1 1/3 2-WIRE REF R1=2/3
FIGURE 6. TORQUE SYSTEM
2 RH
11/3
2/3
REF IN
D/S
ZSO=8.6
REF
REF IN D/S ZSO=8.6 REF
ACTIVE LOAD
RL
TORQUE LOAD WITH DISCRETE EXTERNAL RESISTOR
NOTES: R1 + R2
ZSS
FIGURE 5. EQUIVALENT 2-WIRE CIRCUIT
FIGURE 7. D/S EQUIVALENT
4
S1 RH S2 REF IN RL D/S S3
1.33 S1 1.33 1.33 S2 TR S3 REF
FIGURE 8. D/S - ACTUAL HOOK-UP
C1 RH
2 A B
1 1/3
R1 2/3
REF IN RL C2
D/S C
Zso=8.6
REF
FIGURE 9. IDEAL NULL CONDITION
+15VDC +
+15V 2 2
+V
D/S
10.2V
10.2V
D/S
-V
- 15V
-15VDC
-V
FIGURE 10. WORST CASE 180 ERROR
FIGURE 11. PROTECTION CIRCUITRY
5
200 ns min. TRANSPARENT LATCHED
DATA 1-16 BITS
,,,, ,,,,,
50 ns min. 100 ns min.
FIGURE 12. LL, LM, LA TIMING DIAGRAM
TABLE 2. DSC-10510 PIN FUNCTIONS PIN 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 NAME D01 D02 D03 D04 D05 D06 D07 D08 D09 D010 D011 D012 D013 D014 D015 D016 RL RH S1' S1 S2 S3 +V -V S2' S3' NC GND -15 V +15 V LA LL LM RL' RH' -R (TP) EN FUNCTION Digital Input 01 (MSB) Logic "1" enables. Digital Input 02 Digital Input 03 Digital Input 04 Digital Input 05 Digital Input 06 Digital Input 07 Digital Input 08 Digital Input 09 Digital Input 10 Digital Input 11 Digital Input 12 Digital Input 13 Digital Input 14 Digital Input 15 Digital Input 16 (LSB) 26 Vrms Reference Low Input 26 Vrms Reference High Input Synchro S1 Remote Sense Output Synchro S1 Output Synchro S2 Output. Synchro S3 Output Power Stage +V Power Stage - V Synchro S2 Remote Sense Output Synchro S3 Remote Sense Output No connection. Ground Power Supply Power Supply 2nd Latch All Enable. Input enables dual latch. 1st Latch LSBs Enable. Enables bits 9-16. 1st Latch MSBs Enable. Enables bits 1-8. 3.4 Vrms Reference Low Input 3.4 Vrms Reference High Input No connection. Factory test point. Enable. Power stage enable input allows for digital shutdown of power stage. Gives complete control of converter to digital system. Battle Short Input. Logic 0 overrides over temperature protection. Built-ln-Test Output. Logic 0 when loss of reference, loss of 15 VDC supply, case temperature of +140C, EN input signal, or an output over-current has been detected. Power output stage is turned off unless BS is at 0. Kick. Input used for reducing excessive current flow in torque receiver loads at false null.
1.140 (28.96) 20 21
0.17 MIN (4.32)
0.018 0.002 (0.46 0.05) DIA PIN
2.14 (54.36)
19 EQ. SP. 0.100 = 1.9 TOL. NONCUM (2.5 = 48.3)
1 0.900 (22.86) 0.120 0.002 (3.05 0.05) BOTTOM VIEW
40
0.120 0.002 (3.05 0.05) 0.200 MAX (5.08) SIDE VIEW
38 39
BS BIT
Notes: 1. Dimensions are in inches (millimeters). 2. Lead identification numbers for reference only. 3. Lead cluster shall be centered within 0.10 of outline dimensions. Lead spacing dimensions apply only at seating plane. 4. Pin material meets solderability requirements of MIL-PRF-38534.
40
K
FIGURE 13. DSC-10510 MECHANICAL OUTLINE 40-PIN TDIP
6
ORDERING INFORMATION
DSC-10510-X X X X Supplemental Process Requirements: S = Pre-Cap Source Inspection L = Pull Test Q = Pull Test and Pre-Cap Inspection Blank = None of the Above Accuracy: 3 = 4 minutes 4 = 2 minutes Process Requirements: 0 = Standard DDC Processing, no Burn-In (See table below.) 1 = MIL-PRF-38534 Compliant 2 = B* 3 = MIL-PRF-38534 Compliant with PIND Testing 4 = MIL-PRF-38534 Compliant with Solder Dip 5 = MIL-PRF-38534 Compliant with PIND Testing and Solder Dip 6 = B* with PIND Testing 7 = B* with Solder Dip 8 = B* with PIND Testing and Solder Dip 9 = Standard DDC Processing with Solder Dip, no Burn-In (See table below.) Temperature Grade/Data Requirements: 1 = -55C to +125C 2 = -40C to +85C 3 = 0C to +70C 4 = -55C to +125C with Variables Test Data 5 = -40C to +85C with Variables Test Data 8 = 0C to +70C with Variables Test Data *Standard DDC Processing with burn-in and full temperature test -- see table below. For DSC-10510 use optional Power Transformer, DDC P/N 42359 For S2 Grounded Applications, use Transformer DDC P/N 42929.
STANDARD DDC PROCESSING MIL-STD-883 TEST METHOD(S) INSPECTION SEAL TEMPERATURE CYCLE CONSTANT ACCELERATION BURN-IN 2009, 2010, 2017, and 2032 1014 1010 2001 1015, Table 1 CONDITION(S) -- A and C C A --
7
The information in this data sheet is believed to be accurate; however, no responsibility is assumed by Data Device Corporation for its use, and no license or rights are granted by implication or otherwise in connection therewith. Specifications are subject to change without notice.
105 Wilbur Place, Bohemia, New York 11716-2482 For Technical Support - 1-800-DDC-5757 ext. 7389 or 7413 Headquarters - Tel: (631) 567-5600 ext. 7389 or 7413, Fax: (631) 567-7358 Southeast - Tel: (703) 450-7900, Fax: (703) 450-6610 West Coast - Tel: (714) 895-9777, Fax: (714) 895-4988 Europe - Tel: +44-(0)1635-811140, Fax: +44-(0)1635-32264 Asia/Pacific - Tel: +81-(0)3-3814-7688, Fax: +81-(0)3-3814-7689 World Wide Web - http://www.ddc-web.com
ILC DATA DEVICE CORPORATION REGISTERED TO ISO 9001 FILE NO. A5976
G1-08/99-0
PRINTED IN THE U.S.A.
8

▲Up To Search▲

Price & Availability of DSC-10510-444S

	To Download DSC-10510-444S Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .