The direct current biasing supply unit is regulated in a kind of ultra-low noise high accuracy stepping
Technical field
The utility model relates to the stepping of ultra-low noise high accuracy and regulates the direct current biasing supply unit, relates in particular to the accurate bias supply of multichannel of ultra-low noise, scalable, high stable, high reliability, band remote monitoring function.
Background technology
The DC stable power supply assembly is electronic product indispensable parts in service, and the work that is mainly electronic devices and components provides direct voltage, is indispensable instrument during design, the research and development of electronic product are produced.
In semiconducter device testing or work, often need to produce simultaneously the multichannel bias voltage and offer semiconductor, and require to have low noise, high accuracy, high stability, characteristics such as the visual adjusting of bias voltage.But existing bias supply often can only produce the single channel bias supply, and multichannel is exported different ultra-low noise high accuracy bias voltages simultaneously if desired, and can real time modifying, monitor bias voltage value, this series products is actually rare on market.
The utility model content
The technical scheme that the utility model solved provides a kind ofly to be had bias voltage and can be set arbitrarily by operating personnel, and it can also regulate the direct current biasing supply unit according to the ultra-low noise high accuracy stepping of user's needs output multichannel.
For solving above-mentioned technical problem, the technical scheme that the utility model is taked:
Special character of the present utility model is: comprise the electric weight detection module, micro controller module, the accurate reference voltage module, bias voltage coarse adjustment module, bias voltage accurate adjustment module, CAN bus communication module, host computer, host computer is transferred to micro controller module with the bias voltage parameter of setting by CAN bus communication module, micro controller module arrives bias voltage coarse adjustment module 3 by the SPI protocol transmission after converting parameter to data, bias voltage coarse adjustment module is obtained bias voltage by the contact of migration potential device, the bias voltage of obtaining is by behind the emitter follower, one tunnel process LC filter circuit exports the external signal terminal to, and another road is through A/D back production circuit, bias voltage accurate adjustment module is transferred to micro controller module; Described electric weight detection module is connected with micro controller module through A/D back production circuit, and micro controller module is connected with host computer by CAN bus communication module; Described electric weight detection module is connected with the accurate reference voltage module through the LC filter circuit, and the accurate reference voltage module is connected with the potentiometer of bias voltage coarse adjustment module.
It is the lithium battery of positive and negative 12V that above-mentioned electric weight detection module adopts supply power voltage.
Above-mentioned micro controller module adopts the MC51 single-chip microcomputer, and the chip model is C8051F040.
The chip model that above-mentioned accurate reference voltage module adopts is ADR445.
CAN transceiver model in the above-mentioned CAN bus communication module is CTM8250.
Compared with prior art, the beneficial effects of the utility model:
1, use of the present utility model is flexible, and 8 road bias voltages can be worked simultaneously, can reach bias voltage can be between 0-5.000V be that stepping is arbitrarily set with 2mV;
2, the bias voltage noise of the utility model output is low, is highly suitable for the occasion use that noise has strict demand;
3, communication of the present utility model is stable, and the anti-interference advantage of CAN bus is very obvious;
4, antijamming capability of the present utility model is very strong, and working stability is reliable.
Description of drawings
Fig. 1: connection diagram of the present utility model;
Fig. 2: electric weight detection module principle schematic of the present utility model;
Fig. 3: micro controller module principle schematic of the present utility model;
Fig. 4: accurate reference voltage module principle schematic diagram of the present utility model;
Fig. 5: bias voltage coarse adjustment module principle schematic diagram of the present utility model;
Fig. 6: bias voltage accurate adjustment module principle schematic diagram of the present utility model;
Fig. 7: CAN bus communication module principle schematic diagram of the present utility model.
Embodiment
Below in conjunction with the drawings and specific embodiments the utility model is elaborated.
Referring to Fig. 1, the utility model comprises electric weight detection module 5, micro controller module 1, accurate reference voltage module 4, bias voltage coarse adjustment module 3, bias voltage accurate adjustment module 2, CAN bus communication module 6, host computer 7, host computer 7 is transferred to micro controller module 1 with the bias voltage parameter of setting by CAN bus communication module 6, micro controller module 1 arrives bias voltage coarse adjustment module 3 by the SPI protocol transmission after converting parameter to data, bias voltage coarse adjustment module 3 contacts by the migration potential device obtain bias voltage, the bias voltage of obtaining is by behind the emitter follower, one tunnel process LC filter circuit exports the external signal terminal to, and another road is through A/D back production circuit, bias voltage accurate adjustment module 2 is transferred to micro controller module 1; Described electric weight detects 5 modules and is connected with micro controller module 1 through A/D back production circuit, and micro controller module 1 is connected with host computer 7 by CAN bus communication module 6; Described electric weight detection module 5 is connected with accurate reference voltage module 2 through the LC filter circuit, and accurate reference voltage module 2 is connected with the potentiometer of bias voltage coarse adjustment module 3.
Referring to Fig. 2, electric weight detection module 5 is power modules of system works, adopts pure lithium battery as bias voltage source, can greatly improve the noise objective of system.By 3 road single-pole double throw relays operating state of lithium battery and charged state are freely switched, and lithium battery voltage is by A/D back production circuit, the host computer that information about power is sent to that microcontroller is real-time also shows, thereby the user can be monitored timely to the information about power of lithium battery.
Referring to Fig. 3, micro controller module 1 is the control core of system, and each hardware of system all needs it to coordinate control, the C8051F040 chip of having selected for use Silicon Laboratories company to produce.This microcontroller is 8051 to examine at a high speed, 12 tunnel 12 ADC have been added, 8 tunnel 8 ADC, 1 road high pressure difference is amplified, 2 12 road ADC, a plurality of peripheral hardware resources such as CAN bus 2.0B controller, control 8 road bias voltage work by the SPI agreement, monitor 8 road bias voltages and lithium battery electric weight, carry out information exchange by CAN bus and PC simultaneously, it is greatly convenient to have brought to system design.
Referring to Fig. 4, accurate reference voltage module 4 provides 5V accurate voltage for digital regulation resistance.After the 12V voltage process LC filtering of electric weight detection module 5, changeing the chip piece by ADR445 voltage is 5V voltage with the 12V voltage transitions.The fine setting interface of ADR445 chip inserts digital regulation resistance, can be to electric calibration on the 5V voltage.
Referring to Fig. 5, bias voltage coarse adjustment module 3 is core components that bias voltage is set.Used is AD8403 to main adjusting chip, and AD8403 is that a four roadlock values that include are the digital regulation resistance of 10K, and the sliding contact of every group of potentiometer is 256, communicates by SPI agreement and host computer.Micro controller module is by SPI agreement control bias voltage coarse adjustment module, and to obtain the bias voltage value of setting, described biasing division module is carried out dividing potential drop by the combinational network of three groups of digital regulation resistances, and the dividing potential drop precision is high and stable.5V voltage can be divided into 65536 parts by connected mode with 3 groups of digital regulation resistances, degree of regulation can reach 76.2939uV, realize the requirement that high-accuracy voltage is regulated, the voltage that configures is by penetrating with polar circuit of being made of the AD797 chip, to increase the driving force of bias voltage.
Referring to Fig. 6, the main effect of bias voltage accurate adjustment module 2 is that the setting voltage of bias voltage coarse adjustment module is revised, realization is to the PID control of voltage, monitor bias voltage value in real time, described micro controller module 1 is finely tuned bias voltage according to comparative result by the bias voltage information of obtaining is compared with set information.
Referring to Fig. 7, CAN bus communication module 6 has realized communicating by letter between system and the host computer 7, and C8051F040 microcontroller inside carries the CAN controller, and CANL, CANH signal are by inserting host computer by the DB9 interface after the CAN transceiver CTM8250 module.CTM8250 is that a CAN isolates transceiver, the CAN that this chip internal is integrated is necessary isolates and CAN sending and receiving device, and the major function of chip is that the logic level transition with the CAN controller is the differential level of CAN bus and the isolation features with DC2500V.