In today's intelligent weighing equipment is widely used in the background, high-precision, low-power, multi-functional pricing scale chip has become the core demand of the market. As an integrated circuit designed for electronic pricing scales, CXMC33130-X1 has become the preferred chip for many electronic scale manufacturers with its high-precision 24-bit Sigma-Delta ADC, rich functional interfaces and excellent anti-interference ability.
-
[ CXMC33130 ]"
In today's intelligent weighing equipment is widely used in the background, high-precision, low-power, multi-functional pricing scale chip has become the core demand of the market. As an integrated circuit designed for electronic pricing scales, CXMC33130-X1 has become the preferred chip for many electronic scale manufacturers with its high-precision 24-bit Sigma-Delta ADC, rich functional interfaces and excellent anti-interference ability.
1. Chip Overview and Core Features
The CXMC33130-X1 is a dedicated metering chip integrated with a 24-bit high-precision analog-to-digital converter (ADC) for LED electronic pricing scales. Its core strengths include:
1.1. High precision ADC: Adopt Sigma-Delta architecture to ensure accurate and reliable weighing data.
1.2. Multi-function support: Support unit price storage, peeling, accumulation, counting, single calculation and other practical functions.
1.3. Low power design: With no operation automatic sleep function, significantly extend the device standby time.
1.4. Voltage monitoring: Real-time detection of battery voltage, automatic alarm when low voltage, to avoid data loss.
1.5. Strong anti-interference ability: Built-in anti-voltage fluctuations and electromagnetic interference design to ensure stable operation of equipment.
2. Pin Function and Electrical Characteristics
The chip uses SOP20 package, the pin layout is compact and reasonable, the main interface includes:
2.1.1)PA0-PA7,PB0-PB2Multi-function I/O port, support key scanning, display communication, PWM output, etc.
2.1.2)VINIP/VININ24-bit ADC differential signal input channels.
2.1.3)PB2/ADC8-bit ADC input for voltage detection.
2.1.4)PA4/PWM0、PA5/PWM1: Support buzzer drive and brightness adjustment.
In terms of electrical characteristics, the operating voltage range of the chip is 3.0V-3.6V, supporting an industrial temperature range of -40 ℃ to 85 ℃, with 4000V HBM ESD protection and high reliability.
2.2. Electrical characteristics
3. functional details and practical application
3.1. Weighing and pricing function
The CXMC33130-X1 supports five-digit weight display and six-digit amount display. Unit price and amount support two decimal places. The user can enter the unit price through the key, the system automatically calculates the amount, the operation is simple and intuitive.
3.1.1 Power on
Connect the power switch, all fields will be fully displayed after power on, and "9", "8"... "1", "0" and "a" will be displayed after 0.5 seconds "...
"F", the measuring range, dividing value and voltage will be displayed after 0.5 seconds, and the starting and zeroing range will be detected after 0.5 seconds, which is 10% of the maximum weighing capacity. If it is positive
Normally, it enters the weighing state, and the normal weighing state is as shown in the following figure. If it exceeds the boot reset range, keep the current display and be prompted by the unit price window"
ZeroE ", this state cannot be exited and can only be restarted.
3.1.2 Direct Weighing
When the weighing instrument is in an empty scale state, place the item on the weighing pan (assuming the item weighs 1.5kg), as shown in the figure below;
Enter the unit price of the item, assuming the unit price is 3.80 yuan/kg, type [3][.][8](when the decimal key is valid) or [3][8][0](
When the decimal point key is invalid), see the figure below. If the unit price is 3.85 yuan/kg, type [3][.][8][5] or [3][8][5]. same unit price
The time interval between the input of the two numbers before and after should not exceed 4 seconds (if it exceeds 4 seconds, the system will automatically refresh the list without pressing the [Clear] key.
price).
Remove the item and display it as shown in the left figure. If the item with the same unit price is called, just put it on again. Repeat the above operation at different unit prices.
After weighing and removing the items, press the [Clear] key to clear the unit price, as shown in the following figure.
3.2. Zero setting and peeling function
The zero key quickly zeroes when the empty scale is non-zero or when tare is present, with a valid range of <28% FS. The tare function supports tare weight deduction with an effective range of <20% FS, which is suitable for packaging weighing scenarios.
3.2.1)When the empty scale display is not zero, or there are heavy objects on the weighing pan to be removed, press the [zero] key to return the weight window to zero. The [zero] key is
The effective range is <2% FS, I .e. when the full load is 30kg, the [zero set] key is valid within 600g; If the zero indicator light is on, it means zero.
3.2.2)Place a leather weight on the weighing pan, press the [Tare] key, the weight window will return to zero, and the tare indicator light will be on to indicate that the tare weight will be deducted; remove the leather weight, and weight the window.
Display the weight value of the leather heavy object, press the [Tare] button again, the weight window returns to zero, and the tare indicator light goes out to indicate that the tare operation is exited. The [peeled] key has
The effective range is <20% FS, I .e. when the full load is 30kg, the [peeling] key within 6kg is effective;
3.2.3) Clear
In the cumulative state, press the [Clear] key to clear all cumulative information;
In the weighing state, the unit price input is wrong, you can press the [Clear] key to clear the wrong unit price, and then enter the correct unit price;
In the unit price storage status. The preset unit price is incorrectly entered. You can press the [Clear] key to clear the wrong preset unit price and then enter the correct preset.
Unit price;
In the single-weight state, the single-weight input is wrong, you can press the [Clear] key to clear the wrong single weight, and then enter the correct single weight.
3.3. Accumulation and counting functions.
The cumulative function can record the total amount of multiple transactions, supporting up to 99 cumulative. The counting function can automatically calculate the number of items by inputting single weight or quantity, which is suitable for batch weighing of hardware, parts, etc.
When the same customer purchases multiple items, the amount can be accumulated. For example: A commodity 1.500kg, unit price 5.00 yuan/kg; B
Commodity 0.700kg, unit price 8.00 yuan/kg can be in the following order:
① Put commodity A on the weighing pan, the weight window displays 1.500(kg), and enter the unit price 5.00 (Yuan/kg). At this time, the amount window displays
7.50 (yuan);
② Press the [Accumulate] key, the unit price window displays "Add1", and the amount window displays 7.50 (Yuan), indicating that it has entered the cumulative state;
③ Take off the commodity from the weighing pan and wait for the system to return to the weighing state;
④ Put commodity B on the weighing pan, the weight window displays 0.700(kg), and enter the unit price 8.00 (RMB/kg). At this time, the amount window displays
5.60 (yuan);
⑤ Press the [Accumulate] key to indicate that it has entered the cumulative state, the unit price window displays "Add2", and the amount window displays 13.10 (yuan);
⑥ Operation in sequence, the cumulative number of times can reach 99 times.
Note: When the last cumulative operation is completed, the item must be removed from the weighing pan so that the electronic scale display is reset to zero before the second
The cumulative operation.
Cumulative information clearing: Press the [Accumulate] key to enter the cumulative state, and press the [Clear] key to clear all cumulative information.
Single weight and counting
Press the [Count] key to enter the counting state. The weight window displays normally, the amount window displays "COU-S", and the unit price window needs to enter the quantity manually.
, If the weight is 0.020kg, enter the quantity 1, as shown in the figure below:
Press the [count] key again to calculate the weight/quantity (if the weight or quantity is 0, the [count] key is invalid), and get the single weight (
The weight is accurate to 0.01g, the purpose is to count more accurately), the weight window displays normally, the unit price window displays single weight (in g), and the amount window displays
Show the number of counts, at this time only need to change the number of items on the scale, you can count, as shown in the following figure:
The single weight value will be stored. In the normal weighing state, press the [Single Weight] button to enter the counting state in the above figure, and the unit price window will display the single weight.
(The unit is g), you can enter the specified single weight through the number keys and decimal point keys, and you can also clear the single weight through the [Clear] key. This state
Press the [Single Weight] key again to exit counting and return to normal weighing.
Note: The display after pressing the [Count] key can only be exited by pressing the [Single] key.
3.4. Unit price storage and transfer-out:Users can store common unit price through [M1]-[M4] key, quickly retrieve and improve work efficiency. The stored unit price cannot be deleted, but can be overwritten and updated.
3.4.1)Unit price storage and transfer-out
Storage: press the [storage] key, the amount window displays "SAVE", press the number key and decimal point key to enter the preset unit price, such as 3.25 yuan, press
[3][.][2][5] key; Then press the [M1] key, the 3.25 will be saved to the single preset price 1, press the [M1] key, the unit price window will display "3.25", table
The save was successful. Other unit price storage methods are consistent with the above.
Transfer out: Press the [MX] key to transfer out the default unit price stored in [MX].
Note: the stored default unit price cannot be cleared, but can only be overwritten.
3.5. Voltage and brightness management
The chip supports three-level LED brightness adjustment and adapts to different ambient light. The voltage detection function can prompt low power when the voltage is lower than 3.9V, alarm and prohibit weighing when the voltage is lower than 3.6V, so as to protect the safety of equipment and data.
3.5.1) Voltage detection
Press the [Voltage] key, the weight window shows the range, the unit price window shows the division value, and the amount window shows the current dry/battery voltage, as shown in the following figure
Shown:
3.5.1) Brightness adjustment
TA6932 drive LED digital tube display, support three adjustable brightness, press the [brightness] key cycle to adjust the brightness.
4. Application Circuit and System Integration
The CXMC33130-X1 can be seamlessly connected with the LED driver chip (such as TA6932) to build a complete electronic scale system. Typical application circuits include:
4.1. Sensor signal conditioning circuit
4.2. Key scan matrix
4.3.LED digital tube driver interface
4.4. Buzzer drive circuit
4.4. Power management module (such as LDO)
The system supports AC/DC power supply, with charging status indication, suitable for switching of kg/kg units to meet the needs of the global market.
5. packaging and reliability
The chip is packaged in SOP20, which is compact in size and convenient for PCB layout. All pins meet industrial-grade ESD protection standards for reliable operation in dry, electrostatic environments.
6. epilogue
With its high integration, high precision and low power consumption, CXMC33130-X1 are widely used in commercial electronic scales, industrial metering equipment, intelligent retail terminals and other fields. Its rich functional interfaces and stable performance provide strong core support for weighing equipment.
Remarks: This article is based on the CXMC33130-X1 chip data sheet, the content is for reference only, please refer to the latest official information.
9. Related Products
| Model | Characteristics | SRAM | OTP space | ADC | IO control port | Timer | Interrupt Source | PWM | Encapsulation form | Remarks |
| CXMC33127 | OTP MCU | 256byte | 8k*16bit | 24bit two channels/8bit * 1 | 8 | 1 | 5 | 2 | SSOP48 | LCD with 18*4 |
| CXMC33128 | OTP MCU | 256byte | 8k*16bit | 24bit two channels/8bit * 1 | 11 | 1 | 5 | 2 | SOP20 | |
| CXMC33129 | OTP MCU | 256byte | 8k*16bit | 24bit two channels/8bit * 1 | 10/13 | 1 | 5 | 2 | SOP16/SOP20 | |
| Model | Characteristics | SRAM | OTP space | ADC | IO control port | Timer | Interrupt Source | PWM | Encapsulation form | |
| CXMC33130 | OTP MCU | 256byte | 8k*16bit | 24bit * 100.00g channel/8bit * 1 | 11 | 2 | 5 | 2 | SOP20 |
