Low-voltage shutdown circuit for medical instrument
By designing a low-voltage shutdown circuit for medical devices, using PMOS tubes, transistors, diodes and resistance to detect battery voltage, automatic power outage is achieved at low power, solving the problem that existing medical devices cannot be automatically cut off, and extending the The service life of the device is provided and intelligent control functions are provided.
Patent Information
- Application Number
- CN202421438132.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-24
- Publication Date
- 2025-02-11
- Estimated Expiration
- 2034-06-24
AI Technical Summary
Existing medical devices cannot automatically power off at low power conditions, resulting in damage or inability to start the equipment, and lack of intelligent control functions.
A low-voltage shutdown circuit is designed, which uses PMOS tube, transistor, diode and resistor to detect the battery voltage through the discharge of capacitor C1 and the conduction of transistor Q6, and automatically reminds the user and shuts down the device when the power is low.
It realizes automatic power outage at low power conditions, protects the equipment, extends service life, and provides intelligent control functions to avoid the risk of equipment being damaged or unable to start due to low low voltage.
Smart Images
Figure CN222464585U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the electronics industry, and in particular relates to a low-voltage shutdown circuit for medical equipment. Background Art
[0002] In the current existing technology, the battery voltage of many medical devices powered by rechargeable batteries will decrease as the power decreases. If the power supply voltage is too low, it may cause damage to the equipment. The motor is a key component in medical devices. If the voltage of the motor is too low by more than 10%, the motor current will increase, the winding temperature will rise, and in severe cases, the mechanical equipment will stop running or cannot be started, or even burn the motor.
[0003] Disadvantages of existing technology
[0004] 1. When the battery is low, the device will remain in operation unless the user manually turns off the power. 2. When low battery is detected, the device will remind the user to turn off the device. Repeated reminders will accelerate power consumption. 3. If the user does not use the device for a long time and does not turn it off, the device cannot turn off the power automatically. 4. It is not convenient for intelligent control. Summary of the invention
[0005] The utility model aims to provide a novel low-voltage shutdown circuit, which can cut off the power supply to the electrical equipment when the battery voltage drops to a set value, thereby extending the service life of the equipment.
[0006] The technical solution of the utility model is composed of the following parts: a PMOS tube Q2, transistors Q1, Q5, Q6, a diode D1, resistors R1, R2, R3, R4, R5, R6, R7, R8, R9 and a capacitor C1.
[0007] The voltage of the rechargeable battery will decrease as the power is reduced. The power on / off control is set to high by default. When the battery voltage is normal, the capacitor C1 is charged through the resistor R4 and the diode D1. BAT When it decreases, C1 discharges and the voltage of Q6's e-pole remains at V BAT *R3 / (R3+R4)-0.7V, and the voltage of the b pole of Q6 decreases. At a certain moment, the voltage difference between the e pole voltage and the b pole voltage of Q6 is greater than the conduction voltage U of Q6. eb When the power is low, Q6 and Q5 are turned on, and the low battery detection changes from 3.3V to 0V. The MCU detects the low level, reminds the user and saves the data, then sets the power control to the bottom to complete the shutdown.
[0008] The voltage threshold is set by adjusting the ratio of R1 to R2. The duration of the circuit outputting the low battery signal is achieved by adjusting the capacitance of C1 and the resistance of resistors R5, R6, and R8.
[0009] Beneficial effects of the utility model:
[0010] Medical devices are generally expensive. The utility model ensures that the device does not operate under low voltage conditions, which can well protect the device and extend its service life. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Figure 1 This is a circuit connection diagram of the utility model. DETAILED DESCRIPTION
[0012] In order to enable those skilled in the art to better understand the present invention and make the above-mentioned purposes, features and advantages more obvious and understandable, the present invention is further described in detail below in conjunction with embodiments.
[0013] like Figure 1 As shown, a low-voltage shutdown circuit for medical equipment is composed of the following parts: a PMOS tube (Q2), a triode (Q1, Q5, Q6), a diode (D1), resistors (R1, R2, R3, R4, R5, R6, R7, R8, R9) and a capacitor (C1).
[0014] The voltage of the rechargeable battery will decrease as the power is reduced. The power on / off control is set to high by default. When the battery voltage is normal, the capacitor C1 is charged through the resistor R4 and the diode D1. After stabilization, after the voltage is divided by R3 and R4, the left side of D1 is V BAT *R3 / (R3+R4). After passing through D1, the voltage is reduced by a diode drop, that is, 0.7V, and finally the voltage of capacitor C1 is charged to V BAT *R3 / (R3+R4)-0.7V. After the power supply is stable, the b pole of Q6 is the power supply voltage. Since the voltage of the b pole is higher than that of the e pole, the transistor Q6 is not turned on. If Q6 is not turned on, there is no voltage at the b pole of Q5, and Q5 is also not turned on.
[0015] When V BAT When it decreases, C1 discharges and the voltage of Q6's e-pole remains at V BAT *R3 / (R3+R4)-0.7V, and the voltage of the b pole of Q6 decreases. At a certain moment, the voltage difference between the e pole voltage and the b pole voltage of Q6 is greater than the conduction voltage U of Q6. eb When Q6 is turned on, Q5 is turned on, and the low battery detection changes from 3.3V to 0V. The MCU detects the low level, reminds the user and saves the data, then sets the power control to the bottom to complete the shutdown.
[0016] The voltage threshold is set by adjusting the ratio of R1 to R2. The duration of the circuit outputting a low-battery signal is adjusted by adjusting the capacitance of C1 and the resistance of resistors R5, R6, and R8. For example, increasing the values of C1, R5, R6, and R8 can extend the discharge time of C1, which in turn extends the time Q2 continues to pull low, and ultimately extends the duration of the circuit outputting a low-battery signal.
Claims
1. A low voltage shutdown circuit for medical equipment, characterized in that: It consists of PMOS tube Q2, transistors Q1, Q5, Q6, diode D1, resistors R1, R2, R3, R4, R5, R6, R7, R8, R9 and capacitor C1. The voltage of the rechargeable battery will decrease as the power decreases. The power on / off control is set high by default. When the battery voltage is normal, the capacitor C1 is charged through resistor R4 and diode D1. When V BAT When it decreases, C1 discharges and the voltage of Q6's e-pole remains at V BAT *R3 / (R3+R4)-0.7V, and the voltage of the b pole of Q6 decreases. At a certain moment, the voltage difference between the e pole voltage and the b pole voltage of Q6 is greater than the conduction voltage U of Q6. eb When the power is low, Q6 and Q5 are turned on, and the low battery detection changes from 3.3V to 0V. The MCU detects the low level, reminds the user and saves the data, then sets the power control to the bottom to complete the shutdown.
2. A low voltage shutdown circuit for medical equipment according to claim 1, characterized in that: The voltage threshold is set by adjusting the ratio of R1 to R2.
3. A low voltage shutdown circuit for medical equipment according to claim 1, characterized in that: The duration of the circuit outputting the low battery signal is achieved by adjusting the capacitance of C1 and the resistance values of resistors R5, R6 and R8.