1.Features (see Fig. 1 for outside view, and Table 1 formodels)
|
Compatible with DTL/TTL/CMOS level |
 |
|
12-bit, 14-bit and 16-bit resolution |
|
|
Short-circuit and overload protection |
|
|
Metal case, with good heat rejection |
|
|
Output power: 5W |
Table1 Product models
|
12-bit |
14-bit |
16-bit |
|||
|
Synchro |
Resolver |
Synchro |
Resolver |
Synchro |
Resolver |
|
MDSC2912-411 |
MDRC2912-418 |
MDSC2914-411 |
MDRC2914-418 |
MDSC2916-411 |
MDRC2916-418 |
|
MDSC2912-412 |
MDRC2912-438 |
MDSC2914-412 |
MDRC2914-438 |
MDSC2916-412 |
MDRC2916-438 |
|
MDSC2912-421 |
MDRC2912-414 |
MDSC2914-421 |
MDRC2914-414 |
|
MDRC2916-414 |
|
MDSC2912-422 |
MDRC2912-415 |
MDSC2914-422 |
MDRC2914-415 |
|
MDRC2916-41-36/11.8 |
|
|
|
|
|
|
MDRC2916-415 |
2. Scope of application of MDSC/MDRC29 Series Digital to Synchro Converters or Digital to Resolver Converters
Military servo control systemAntenna system
Radar measurement system
Navigation system
Cannon control system
Machine tool control
3. Description of MDSC/MDRC29 Series Digital to Synchro Converters or Digital to Resolver Converters
MDSC/MDRC29 series product is a converter that converts the input binary signal to that of synchro or resolver. The input signal is compatible with DTL/TTL/CMOS level, and the output is 3-wire synchro or 4-wire resolver signal. This series of product continuously tracks the input 2-bit/14-bit/16-bit binary data, and outputs high-precision synchro/resolver signal after conversion. The product is equipped with power amplification circuit inside it, and its output power can reach 5W.
4. Electrical performance (Table 2 and Table 3) of MDSC/MDRC29 Series Digital to Synchro Converters or Digital to Resolver Converters
Table 2 Rated conditions and recommended operating conditions|
Max. absolute rating value |
Supply voltage +VS: +13.5~+17.5V Supply voltage -VS: -17.5~-13.5V Storage temperature range: -40~100℃ |
|
Recommended operating conditions |
Supply voltage +VS: +14.5~+16.5V Supply voltage -VS: -16.5~-14.25V Reference voltage (effective value) VRef*: 115V±5% Signal voltage (effective value) V1*: 90V±5% Reference frequency f*: 400Hz±10% Range of operating temperature TA: -40℃~85℃ |
Table 3 Electric characteristics
|
Parameter |
MDRC/DSC2912 |
MDRC/DSC2914 |
MDRC/DSC2916 |
Unit |
|||
|
Enterprise military standard (Q/HW30857-2006) |
|||||||
|
Resolution |
12-bit |
14-bit |
16-bit |
Bit |
|||
|
Accuracy |
±8 |
±4 |
±4 |
Minute |
|||
|
Digital input |
5 |
0 |
5 |
0 |
5 |
0 |
V |
|
Reference voltage (effective value) |
26, 36, 115V±10%﹡ |
V |
|||||
|
Reference frequency |
50, 400, 1.2K, 2K﹡ |
Hz |
|||||
|
Output signal voltage (Effective value) |
11.8, 26, 36, 90 (line-line, resolver or synchro)﹡ |
V |
|||||
|
Output power |
5 |
W |
|||||
5. Operating principle (Fig. 2 and Fig. 3) of MDSC/MDRC29 Series Digital to Synchro Converters or Digital to Resolver Converters
One of the distinctive characteristics of MDSC/MDRC29 series product is that it can neglect the change of radius vector. Each type of digital-to-syncrho/resolver converter must be provided with output sin and cos function signal, however, since the law of sin and cos function is not precisely all the time, its error can reach as high as ± 7%. In practical use, this error is not serious sometimes, but it is not allowed in the application of tracking rotating torque receiver or servo control loop. For MDSC/MDRC29 series product, this error can be reduced below 0.1%, which means that when the converter is used in a closed loop servo system, the closed-loop gain is independent of the input signal, thus avoiding undesired error resulting from change of reference signal.
 |
 |
|
Fig.2 Schematic diagram for DSC converter |
Fig.2 Schematic diagram for DRC converter |
6. Connection diagram for typical application (Fig. 4) of MDSC/MDRC29 Series Digital to Synchro Converters or Digital to Resolver Converters
DSC/DRC load connection（1）Control transformer (CT)
The simplest design is using digital converter to synchro/resolver to drive the control transformer.
The min. power for driving CT is:
Where, V is line-line voltage, Zso is the impedance between nodes after the circuit from one output end of CT to other two rotor circuits is short-circuited (Zso=Rso+jXso).
For example: when the impedance of CT is ZS=700+j490, the line-line voltage is 90V, then
Fig. 4 Connection diagram for typical application
For the adjustment of CT load, it can be reduced through 3 capacitances at the output end, as shown as below:
The required power is: (VA) (unadjusted) x
In the above example, the capacitance is:
The required power after adjustment is:
In the design, it is required to note the errors that usually exist such as coil number, capacitance, inductance, etc. in CT.
Practical prompts for CT load adjustment:
① High precision capacitance is not required, an error of 20% is enough.
② Three capacitors must be used between S1 and S2, S2 and S3 as well as S3 and S1.
③ Withstand voltage and type of capacitance
For line-line voltage of 11.8V, the withstand voltage of capacitance between pins is 25VAC, and the type of capacitance is non-polar tantalum capacitance.
For line-line voltage of 90V, the withstand voltage of capacitance between pins is 150VAC, and it is allowed to use ceramic capacitance with low dielectric constant.
④ The load adjustment of resolver only requires two capacitances. One is connected between S1 and S3, and the other between S2 and S4.
（2）Control differential transducer (CDX)
The load of DSC in the equipment can be considered like CT load, but its equivalent impedance Z must be calculated like CT load, its value is generally 66%~80% of ZSO.
（3）Torque receiver (TR)
Compared with CT and CDX, it is relatively difficult to control the torque receiver (TR). Generally speaking, it requires an output amplifier. Because the change of radius vector of MDSC/MDRC28 series product can be neglected, it is more suitable for controlling TR than those devices with an error of ±7%. For an error with angle θ, the exciting current is:
Prompts:
①TR should not be blocked.
②The corresponding advance from reference input end to DSC shall conform to the provisions of TR.
③The reference input must be always applied on TR and converter.
The output voltage of DSC/DRC must completely match with the voltage required by TR.
7. MTBF curve (Fig. 5) of MDSC/MDRC29 Series Digital to Synchro Converters or Digital to Resolver Converters |
8. Pin designation (Fig. 6, Table 4) of MDSC/MDRC29 Series Digital to Synchro Converters or Digital to Resolver Converters |
 |
 |
|
Fig.5 MTBF-temperature curve (Note: according to GJB/Z299B-98, envisaged good ground condition) |
Fig.6 Schematic diagram of pins (top view) |
Table 4 Pin designation
|
Pin |
Symbol |
Function |
Pin |
Symbol |
Function |
Pin |
Symbol |
Function |
|
1 |
1 (MSB) |
Digital input 1 |
11 |
11 |
Digital input 11 |
21 |
S1 |
Signal output 1 |
|
2 |
2 |
Digital input 2 |
12 |
12 |
Digital input 12 |
22 |
+15V |
+15V input |
|
3 |
3 |
Digital input 3 |
13 |
13 |
Digital input 13 |
23 |
GND |
Ground |
|
4 |
4 |
Digital input 4 |
14 |
14 |
Digital input 14 |
24 |
NC |
Leave unconnected |
|
5 |
5 |
Digital input 5 |
15 |
15 |
Digital input 15 (12-bit and 14-bit are lefe unconnected) |
25 |
-15V |
-15V input |
|
6 |
6 |
Digital input 6 |
16 |
16 |
Digital input 16 (12-bit and 14-bit areleft unconnected) |
26 |
NC |
Leave unconnected |
|
7 |
7 |
Digital input 7 |
17 |
NC |
Leave unconnected |
27 |
RLo |
Low end of reference input |
|
8 |
8 |
Digital input 8 |
18 |
S4 |
Signal output 4 |
28 |
RHi |
High end of reference input |
|
9 |
9 |
Digital input 9 |
19 |
S3 |
Signal output 3 |
|
|
|
|
10 |
10 |
Digital input 10 |
20 |
S2 |
Signal output 2 |
|
|
|
Notes: ① Digital input: DSC/DRC2912 is 1~12, altogether 12 bits;
DSC/DRC2914 is 1~14, altogether 14 bits; DSC/DRC2916 is 1~16, altogether
16 bits.
② “1” is the highest bit (MSB);
③ S1, S2, S3 and S4: output are used for synchro or resolver, among them, S4 is only used for resolver;
④ RHi and RLo: reference input;
⑤GND: common ground of power supply and input signal;
⑥±15V: power supply.
9. Table of weight values (Table 5) of MDSC/MDRC29 Series Digital to Synchro Converters or Digital to Resolver Converters
Table 5 Table of weight values|
Bit |
Angle |
Bit |
Angle |
Bit |
Angle |
|
1 |
180.000 0 |
6 |
5.625 0 |
11 |
0.175 8 |
|
2 |
90.000 0 |
7 |
2.812 5 |
12 (for 12-bit LSB) |
0.087 9 |
|
3 |
45.000 0 |
8 |
1.406 3 |
13 |
0.043 9 |
|
4 |
22.500 0 |
9 |
0.703 1 |
14 (for 14-bit LSB) |
0.022 0 |
|
5 |
11.250 0 |
10 |
0.351 6 |
|
|
10. Package specifications (unit: mm) (Fig. 7) of MDSC/MDRC29 Series Digital to Synchro Converters or Digital to Resolver Converters
Fig. 7 Outside view and dimensions of package
11. Part numbering key (Fig. 8) of MDSC/MDRC29 Series Digital to Synchro Converters or Digital to Resolver Converters
Fig. 8 Part numbering key
Note: when the above signal voltage and reference voltage (Z) are non-standard, they shall be given as follows:
(e.g. reference voltage 40V and signal voltage 38V are expressed as -40/38)
Application notes
- Do not apply reference voltage of 115V to the device of 26V.
- The voltage of power supply shall not exceed the specified range.
- Do not connect reference RHi and RLo to other pins.
- Supply voltage must be kept to the voltage of correct polarity.
- When the max. absolute rating value is exceeded, the device may be damaged.
- Upon assembly, the bottom of the product shall fit to the circuit board closely so as to avoid damage of pins, and shockproof provision shall be added, if necessary.
- When the user places an order for the product, detailed electric performance indexes shall refer to the relevant enterprise standard.
