[abstract]This article introduced one kind realizes the plan by the high speed monolithic integrated circuit C8051F015 control’s handhold electricity stimulator, introduced specifically the entire plan’s design concept as well as the software and hardware realize. This design may use in the family and the community resident’s healthcare, has certain use value.
[key word]Healthcare electricity stimulator C8051F015 clock chip
1. introduction
Along with society’s unceasing progress, people’s health consciousness strengthens unceasingly, the family health instrument obtains is getting more and more widespread the application. The electricity stimulator is produces a sequence voltage perhaps the current pulse health care instrument. Through transmits the electricity in the nerve perhaps the Muscular tissue, achieves the diagnosis perhaps the healthcare goal. Looking from the biology viewpoint, the organism excited organization can have the response to the outside stimulation, but only then may control its parameter precisely to the electricity stimulation. Moreover moderate electricity stimulation, even if will be redundant will not cause the organization to damage many times. The electricity stimulator may depend upon has the current pulse frequency height, causes the electric current after the skin, then the stimulation sensory nerve, often applies in the affable ache aspect, regarding anxious, chronic and the nervous ache has the treatment result.
The present medicine uses electricity the stimulator usually from to become body [1]. But in some large-scale medical equipment, the electricity stimulator only as an equipment’s in constituent, it both must be controlled frequently in the main engine system, and must isolate good with the main system, in order to avoid has the disturbance to main system equipment’s other parts. This article introduced causing the electricity stimulator which controls by the high speed monolithic integrated circuit, the characteristic is the cost is low, the volume is small, the weight light, is advantageous for the family or the community hospital use.
2. Overall design
The hand-hold stimulator system basic function request is as follows.
2.1 equipment’s each pulse widths are the maximum output scope 50%, the pulse width is 250μs ±1%.
2.2 equipment pulse’s rising time and the fall time are smaller than 5 μs; The pulse goes against falls is smaller than 2%, is the square pulse. When random output current or load the output wave shape is not distorted.
2.3 equipment output amplitude when is biggest, when rated load impedance for 0~6kΩ, the inflow load’s electric current is 80mA, but is not bigger than 80mA. Output current for constant invariable, constant flow error ±1%.
2.4 equipment’s rated load impedance for 0~6kΩ, when the loaded impedance is bigger than 6kΩ, the cut-off output (electric current and voltage are 0), and reports to the police. The equipment outputs the direct component is zero.
2.5 equipment output amplitude’s adjustment should be continuously even, the profile is not distorted, the minimum output is not bigger than the maximum output 1%.
when 2.6 equipment opening survey, the output voltage peak value should not be bigger than 500V.
According to the above request, the system uses the monolithic integrated circuit to take the master control chip together. Considered grasps equipment’s request, the choice 4×1.2V nichrome battery takes the electric power supply, and chooses the appropriate power source management chip, enhances system’s period of revolution, and may output the 12V DC voltage through the adapter to carry on the charge, coordinates the software gathering battery voltage parameter, real-time computation battery surplus capacity, when low electric quantity buzzing warning user. Uses the pressure to control the constant current the method, opens fast with the closure electric current, causes the pulse rise time and the fall time request. Uses the exterior memory, the record different user’s stimulation parameter. Uses the serial port connection, causes the stimulator and the PC function convenient carries on the correspondence. Uses LCD, the design graph writing contact surface, the simplicity of operator, enhances system’s convenient [2] large scale.
3. hardware design
Used the C8051F015 monolithic integrated circuit to take system’s master control chip [3], the liquid crystal display and the keyboard has realized the man-machine conversation function. The DataFlash space is big, saves various record numbers correspondence the stimulation parameter, the FRAM permission many read-write number of times, real-time preserved current user’s stimulation parameter, and when close-down data storage DataFlash. The clock chip provides the system real-time clock, including year, month, Japan, divides, the second, carries on the data transmission through the serial port and PC machine. The acceleration instrument uses in examines the human body to shiver the situation, the signal after the reshaping, the enlargement and filter processing, inputs monolithic integrated circuit’s ADC port.
C8051F015 is Silicon a Labs Corporation’s model of monolithic integrated circuit, integrates completely the composite signal system-on-a-chip (SoC), has with 8051 compatible high speed CIP-51 essences, is completely compatible with the MCS-51 set of instructions, the outside has the rich IO resources, internal integrated 2304 byte data RAM and 32K byte Flash,10 the position ADC module and two 12 DAC and two simulation comparator, can satisfy the system to the hardware source request. In addition, in this chip has the overlapping switch module, through the establishment, may control the register the internal counter/timer, the serial main line, the hardware interrupt, the ADC transformation enable input, the comparator to output as well as the micro controller interior other digital signal disposition to appear in the port I/O pin. This permission user acts according to own specific application choice general port I/O and needs the digital resources the combination, simplified on hardware circuit’s design, enhances system’s reliability, reduces the production cost. LCD uses 128×64 YM12864 LCD module. FRAM uses RAMTRON Corporation’s FM25256, the capacity is 256K. DataFlash uses Atmel Corporation’s AT45DB081B, the capacity is 8M. The clock chip uses RICOH Corporation’s RS5C348A. Uses SPI connection FRAM, Flash and the clock chip can save the I/O resources. Uses these commonly used chips both to be able to reduce the expenditure, and may guarantee the ample supply and prompt delivery.
C8051F015 and FM25256, AT45DB081B, RS5C348A connection connection as shown in Figure 2.
Power source management chip’s hardware connection as shown in Figure 3, the chip uses MAX712, in the chart Vin is the input voltage, V_B meets the battery both sides, when charge LED opens, the system may when the charge uses. May also by the 12V direct-current power supply power supply and to the battery charge, carries when may supply power by 4×1.2V the nichrome battery.
The pressure-rise part’s electric circuit connection, as shown in Figure 4, uses National Semiconductor Company’s pressure-rise chip LM2577 is a core, front end uses MOSFET to connect 2577 ground terminals to achieve the control the goal, the out-port connects the FB end through the feedback resistance, the reaction control output voltage.
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Figure 2 C8051F015 and memory, clock chip connection diagram
Figure 3 power source management chip hardware connection like chart
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Figure 4 pressure-rise part electric circuit connection |
4. Software design
The equipment system divides into 4 patterns: Initialize the system, menu pattern, playbacking pattern and stimulation pattern.
Figure 5 equipment system’s phase transition schematic drawing
(1) Initialize the system
The executive system initialization work, LCD demonstrates welcome information.
(2) Menu pattern
The response keyboard operation, additional and the revision record number and the corresponding stimulation parameter, realizes the man-machine conversation, including electric current, pattern, personnel, playbacking, connection, sound, back light, time, memory and starting value.
The choice electric current, the determination intensity of stimulation (1~80mA), the default value is 60mA. Choice stimulation, determination stimulation pattern (STC, TS, TOF, DBS and PTC). Chooses the personnel, definite record number, establishment scope: 000~999. Choice playbacking, enters the playbacking pattern. Choice connection, after serial port and PC correspondence. Choice sound and back light, definite sound and LCD back light switch. Selecting time, revision and definite time. The choice memory, examined that the existing record occupies total memory the percentage. The choice starting value, may reset the memory, all establishes the default value.
(3) Playbacking pattern
Examined that each record correspondence the stimulation parameter, chooses the corresponding record number, enters the stimulation pattern. Under this pattern cannot revise the stimulation parameter.
(4) Stimulation pattern
When stimulation, may act according to LCD the demonstration, responds the keyboard operation, makes the adjustment to the stimulation parameter, and preserves. Under certain non-cyclical stimulation pattern, needs the user pressed key to stimulate the time interval to carry on the control.
This series primary mission is the LCD writing contact surface demonstration and the response user’s pressed key operation, therefore the procedure main loop is the pressed key response procedure, simultaneously to its third-level menu altogether 40 condition, carries on the difference with a 8 bit status character and compared to right. Third-level menu’s condition character’s high 2bit, expressed that 0 levels of four conditions, after that 4bit expressed 1 level of ten conditions, low position 2bit expresses the final level sub-condition, only then the time pattern uses to 4.
System essential record current condition character and on a condition character, according to its reciprocity decision user input order content, then execution response operation.
6. System effect
Stimulates under the pattern, LCD demonstration as shown in Figure 6.
Figure 6 under stimulation pattern LCD demonstration
6.1 static note numbers, located at display monitor left underneath. The record number demonstrated that located at display monitor left under base, under static note number.
6.2. The clock demonstrated that located at the display monitor upper left side. Is apart from the next time execution stimulation time, located at display monitor on left underneath, under clock demonstration.
6.3 electric quantities demonstrated that when the electric quantity has 30% sends out the warning, on right goes against the side located at the display monitor. The stimulation pattern demonstrated that located at display monitor on right underneath, under electric quantity demonstration.
6.4 current intensities of stimulation demonstrated that the unit is mA, demonstrated immediately, located at display monitor on right underneath.
6.5 T1/Tc percentages demonstrated that the unit for %, demonstrated immediately, located at display monitor in place above.
6.6 T4/T1 percentages demonstrated that the unit for %, demonstrated immediately, located at display monitor central side.
6.7 feedback signal intensity (column bar line demonstrated by the histogram that vertical line for feedback signal intensity demonstrated immediately highly), located at entire display monitor’s among.
7. Subtotal
Because the system various components request’s voltage are many, and needs to produce the highest 500V stimulation voltage, transfer efficiency’s influence, needs to compare the high-capacity the battery, in later may consider that uses a higher efficiency the voltage transformation chip, enables the system to move a longer time. Moreover, this system can only carry on the stimulation to a spot, may improve in the later system for many stimulation outputs, causes the system to be more satisfied the actual need. When design next generation product, may consider that may transplant operating system’s embedded chip and the bigger LCD display monitor, causes the user graphical interface change in the operation, causes the system user-friendlier.
This article author innovates the spot: The circuit design is novel, healthcare instrument miniaturization, portable, has filled the market blank.
Reference:
[1] once rock pile nerve stimulator’s preliminary study China knew net outstanding abundant master the paper 2004(5)
[2] Zhang Jiangli Man Chengyi uses electricity stimulator’s development electrician electrical energy new technology [J] 1995(4)
[3] C8051F010/1/2/5/6/7 Mixed-Signal 32KB ISP FLASH MCU Datasheet
http://www.xhl.com.cn/sjsc/sjscdetail.asp?sid=16
[4] Pang buddhist hymn sung to flute accompaniment Sun Tongjing Qin Weigang based on C8051F330 monolithic integrated circuit’s multi-channel humiture observation system micro computer information [J] in 2004 20 volumes 4 issues, 51-52 pages
