Multi-channel furnace temperature acquisition device based on multi-layer cascaded analog switch circuit
By using a multi-channel furnace temperature acquisition device based on a multi-layer cascaded analog switch circuit, the problems of limited temperature measurement range and electromagnetic interference in the integrated circuit packaging process are solved. High-speed and high-precision multi-channel temperature acquisition is achieved, which is suitable for measuring the furnace temperature of integrated circuit packaging in large spaces and with strong electromagnetic interference.
Patent Information
- Application Number
- CN202111663865.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2021-12-30
- Publication Date
- 2025-12-30
- Estimated Expiration
- 2041-12-30
AI Technical Summary
Existing temperature measurement devices in the integrated circuit packaging process suffer from problems such as limited temperature measurement range, susceptibility to electromagnetic interference, few channels, slow temperature measurement speed, and complex deployment, making it difficult to meet the multi-channel temperature measurement requirements of large-space, high-temperature welding environments.
A multi-channel furnace temperature acquisition device based on a multi-layer cascaded analog switch circuit is adopted, including a temperature information acquisition module, a multi-channel signal selection module, a temperature signal processing module, an MCU module, a power supply module, a storage module, and a display module. It utilizes a K-type thermocouple, an electromagnetic shielding layer, a ceramic shell, and a grounding bus, combined with an STM32F103 series ARM core processor and a MAX6675 analog-to-digital converter, to achieve high-speed and high-precision multi-channel temperature acquisition.
It achieves high-speed, reliable, accurate and wide-range multi-channel temperature acquisition in environments with strong electromagnetic interference, and is suitable for temperature measurement in integrated circuit packaging furnaces with large spaces and strong electromagnetic interference.
Smart Images
Figure CN114323325B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a furnace temperature acquisition device used in the field of integrated circuit packaging, specifically a multi-channel furnace temperature acquisition device based on a multi-layer cascaded analog switch circuit. Background Technology
[0002] Modern semiconductor integrated circuit packaging involves multiple high-temperature soldering processes, and the furnace temperature profile is a crucial factor affecting soldering quality. Deviations in furnace temperature parameters often lead to numerous cold solder joints, thus affecting the reliability and hermeticity of the integrated circuit package and rendering the circuit unusable. However, due to the large space of most soldering furnaces, improper design of the heating area or environmental interference can cause significant deviations between the actual and set temperatures in some areas, thereby affecting the soldering effect.
[0003] Currently, most temperature measurement devices use PT100 resistance temperature detectors (RTDs), which have limited measurement range and are unsuitable for measuring the temperature of integrated circuit packaging furnaces. Some temperature measurement devices using K-type thermocouples suffer from problems such as limited measurement channels, susceptibility to interference from high electromagnetic radiation environments, complex implementation, slow measurement speed, incomplete temperature measurement functions, and cumbersome deployment. Therefore, to meet the needs of large-space, high-electromagnetic-interference environments and multi-channel temperature measurement, there is an urgent need to develop a multi-channel furnace temperature acquisition device based on multi-layer cascaded analog switches. Summary of the Invention
[0004] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a multi-channel furnace temperature acquisition device based on a multi-layer cascaded analog switch circuit, which features high speed, high reliability, high precision and wide measurement range.
[0005] According to the technical solution provided by the present invention, the multi-channel furnace temperature acquisition device based on multi-layer cascaded analog switch circuit includes a temperature information acquisition module, a multi-channel signal selection module, a temperature signal processing module, an MCU module, a power supply module, a storage module, and a display module.
[0006] The power module is connected to the multi-channel signal selection module, the temperature signal processing module, the MCU module, the storage module, and the display module. The output of the temperature information acquisition module is connected to the first input of the multi-channel signal selection module, the output of the multi-channel signal selection module is connected to the second input of the temperature signal processing module, the first input / output of the temperature signal processing module is connected to the first input / output of the MCU module, the second input / output of the MCU module is connected to the first input / output of the storage module, the third output of the MCU module is connected to the second input of the multi-channel signal selection module, and the fourth output of the MCU module is connected to the input of the display module.
[0007] Preferably, the temperature information acquisition module includes a K-type thermocouple, an electromagnetic shielding layer, a ceramic shell, and a grounding bus.
[0008] The ceramic shell encloses the temperature probe of the K-type thermocouple, which is enclosed by an electromagnetic shielding layer connected to the grounding bus.
[0009] Preferably, the multi-channel signal selection module includes A m-pole n-throw analog switches, where n ≥ 2m, and the temperature signal processing module includes B analog-to-digital converters, where the value of B is equal to the number of MCU signal receiving ports.
[0010] The relationship between the number of cascaded layers l of the multi-channel signal selection module and the analog switch and analog-to-digital converter is as follows: The relationship between the number of temperature measurement channels c and the analog switch and analog-to-digital converter is c = A(nm) + B.
[0011] Preferably, the MCU module is a Cortex-M3 processor with an STM32F103 series ARM core.
[0012] Preferably, the power supply module provides 5V voltage to the multi-channel signal selection module, temperature signal processing module, MCU module, storage module, and display module.
[0013] Preferably, the storage module uses a high-speed TF card with a capacity of 32G.
[0014] Preferably, the display module uses a 3.7-inch color LCD screen.
[0015] This invention meets the need for multi-channel temperature measurement in large spaces and environments with strong electromagnetic interference. At the same time, this invention has the characteristics of high speed, high reliability, high accuracy and wide measurement range. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the principle of the present invention.
[0017] Figure 2 This is a schematic diagram of the minimum functional structure unit of the multi-layer cascaded analog switch circuit in this invention.
[0018] Figure 3 This is a schematic diagram of a 4-layer cascaded analog switch circuit in this invention to achieve a 64-to-4 selection. Detailed Implementation
[0019] The present invention will be further described below with reference to specific embodiments.
[0020] The multi-channel furnace temperature acquisition device based on a multi-layer cascaded analog switch circuit of the present invention, such as Figure 1As shown, it includes a temperature information acquisition module 1, a multi-channel signal selection module 2, a temperature signal processing module 3, an MCU module 4, a power supply module 5, a storage module 6, and a display module 7;
[0021] The power module 5 is connected to the multi-channel signal selection module 2, the temperature signal processing module 3, the MCU module 4, the storage module 6, and the display module 7. The output terminal of the temperature information acquisition module 1 is connected to the first input terminal of the multi-channel signal selection module 2, the output terminal of the multi-channel signal selection module 2 is connected to the second input terminal of the temperature signal processing module 3, the first input / output terminal of the temperature signal processing module 3 is connected to the first input / output terminal of the MCU module 4, the second input / output terminal of the MCU module 4 is connected to the first input / output terminal of the storage module 6, the third output terminal of the MCU module 4 is connected to the second input terminal of the multi-channel signal selection module 2, and the fourth output terminal of the MCU module 4 is connected to the input terminal of the display module 7.
[0022] The temperature information acquisition module 1 includes multiple temperature sensors, which convert the physical temperature signals from multiple temperature measurement points into multiple sets of electrical signals. The multi-channel signal selection module 2 selects all input ports of the signal and connects to the MCU module 4. The MCU module 4 uses the multi-channel signal selection module 2 to sort the multiple sets of electrical signals and then sequentially passes them through the temperature signal processing module 3 for analog-to-digital conversion. The temperature data is read, processed, and stored in the storage module 6 by the MCU module 4, and then displayed in real time on the display module 7.
[0023] The temperature information acquisition module 1 includes a K-type thermocouple, an electromagnetic shielding layer, a ceramic shell, and a grounding bus.
[0024] The ceramic shell encloses the temperature probe of the K-type thermocouple. The K-type thermocouple is enclosed by an electromagnetic shielding layer, which is connected to the grounding bus. The electromagnetic shielding layer can be well grounded. The anodes of all K-type thermocouples are connected to the input terminal of the multi-channel signal selection module 2. The K-type thermocouples measure the furnace temperature at the actual temperature of the ceramic shell. The grounding bus is connected to the cathodes of all K-type thermocouples.
[0025] The minimum functional unit of the multi-channel selection module is constructed using a double-pole four-throw analog switch as an example. The minimum functional unit is as follows: Figure 2 As shown, it includes a first double-pole four-throw analog switch IC1, a second double-pole four-throw analog switch IC2, a third double-pole four-throw analog switch IC3, a first inverter INV1, a second inverter INV2, a first selection signal Control_A, and a second selection signal Control_B.
[0026] The first double-pole four-throw analog switch IC1, the second double-pole four-throw analog switch IC2, and the third double-pole four-throw analog switch IC3 form a two-layer cascaded structure. The cascaded structure, consisting of the first double-pole four-throw analog switch IC1, the second double-pole four-throw analog switch IC2, the first inverter INV1, and the first selection signal Control_A, has 8 signal input channels (the NO1, NO2, NC1, and NC2 control terminals on the first double-pole four-throw analog switch IC1 and the NO1, NO2, NC1, and NC2 control terminals on the second double-pole four-throw analog switch IC2). 2 control terminals and 4 signal outputs (COM1 and COM2 control terminals on the first double-pole four-throw analog switch IC1 and COM1 and COM2 control terminals on the second double-pole four-throw analog switch IC2). The first selection signal Control_A is connected to the IN2 control terminal of the first double-pole four-throw analog switch IC1 and the IN2 control terminal of IC2. The signal after the first selection signal Control_A is inverted by the first inverter INV1 is connected to the IN1 control terminal of the first double-pole four-throw analog switch IC1 and the IN1 control terminal of the second double-pole four-throw analog switch IC2.
[0027] The second layer (the third double-pole four-throw analog switch IC3, the second inverter INV2, and the second selection signal Control_B) has 4 signal inputs (the NO1, NO2, NC1, and NC2 control terminals of the third double-pole four-throw analog switch IC3) and 2 signal outputs (the COM1 and COM2 control terminals of the third double-pole four-throw analog switch IC3). The second selection signal Control_B is connected to the IN2 control terminal of IC3. The signal of the second selection signal Control_B after being inverted by the inverter (INV2) is connected to the IN1 control terminal of the third double-pole four-throw analog switch IC3. The output terminals of the first layer (COM1 and COM2 control terminals of the first double-pole four-throw analog switch IC1 and COM1 and COM2 control terminals of the second double-pole four-throw analog switch IC2) are connected to the input terminals of the second layer (NO1, NO2, NC1, and NC2 control terminals of the third double-pole four-throw analog switch IC3). The output terminals of the second layer (COM1 and COM2 control terminals of the third double-pole four-throw analog switch IC3) output the output signals of the minimum functional unit. The input signals are sequentially output from the module output terminals through a timing conversion channel selection signal.
[0028] Taking a double-pole four-throw analog switch circuit to implement a 64-to-4 signal selection module as an example, such as Figure 3As shown, the implemented 64-to-4 signal selection module includes 64 signal input ports (CH1 control terminal, CH2 control terminal, CH3 control terminal, CH4 control terminal...CH62 control terminal, CH63 control terminal, CH64 control terminal), 4 signal output ports (COM1 control terminal, COM2 control terminal, COM3 control terminal, COM4 control terminal), and 4 selection signals (IN1 control terminal, IN2 control terminal, IN3 control terminal, IN4 control terminal).
[0029] The relationship between the number of cascaded layers l and the analog switches and analog-to-digital converters is as follows: The relationship between the number of temperature measurement channels *c* and the analog switches and analog-to-digital converters is *c* = A(nm) + B, where B equals the number of MCU signal receiving ports. Substituting these values, the 64-to-4 signal selection module has a 4-layer cascaded structure, containing a total of 30 double-pole four-throw analog switch circuits. Each layer of analog switches uses one binary selection signal for control, requiring a total of 4 binary selection signals. The on-resistance *R* of the analog switches should be less than 1 ohm. The double-pole four-throw analog switches are selected from RS2105, with an on-resistance of 0.6Ω, which has a minimal impact on mV-level potential differences. The temperature signal processing module 3 corresponding to the 64-to-4 signal selection module contains 4 MAX6675 analog-to-digital converters. Since the single signal conversion time of each MAX6675 ADC is approximately 180ms, the parallel conversion of 4 MAX6675 ADCs can effectively improve signal conversion efficiency.
[0030] The temperature signal processing module 3, in conjunction with the pull-up ceramic capacitor between the power supply, can effectively prevent power supply coupling noise from interfering with the temperature measurement results.
[0031] Based on the analysis of the device's computing power requirements and microprocessor performance, the MCU module 4 is mainly based on the STM32F103 series ARM core Cortex-M3 processor. It outputs a set of channel selection signals to the multi-channel selection module 2 through the GPIO port to ensure that all channels are turned on and off in sequence. This allows the voltage analog signal generated by the K-type thermocouple to be input sequentially into the MAX6675 analog-to-digital converter of the temperature signal processing module 3. The converted temperature information is then input into the MCU module 4 through the SPI port for software filtering.
[0032] The power module 5 provides 5V voltage to the multi-channel signal selection module 2, temperature signal processing module 3, MCU module 4, storage module 6, and display module 7.
[0033] The storage module 6 uses a 32GB high-speed TF card, connected to the MCU module 4 via a GPIO port, to save the temperature information of each channel in real time. The saved data is in Excel format, and the file naming convention is as follows.
[0034] "0: / %d-%d-%d-%d_%d_%d.xls",calendar.w_year,calendar.w_month,calendar.w_date,calendar.hour,calendar.min,calendar.sec.
[0035] To facilitate real-time monitoring of temperature data for each channel by on-site commissioning personnel and to enable timely adjustment of furnace temperature parameters, the display module 7 uses a 3.7-inch color LCD screen and is connected to the MCU module 4 via a multiplexed SPI interface to display the temperature information for each channel separately.
Claims
1. A multi-channel furnace temperature acquisition device based on a multi-layer cascaded analog switch circuit, characterized by: It includes temperature information acquisition module (1), multi-channel signal selection module (2), temperature signal processing module (3), MCU module (4), power module (5), storage module (6) and display module (7); The power module (5) is connected with the multi-channel signal selection module (2), the temperature signal processing module (3), the MCU module (4), the storage module (6) and the display module (7), the output end of the temperature information acquisition module (1) is connected with the first input end of the multi-channel signal selection module (2), the output end of the multi-channel signal selection module (2) is connected with the second input end of the temperature signal processing module (3), the first input / output end of the temperature signal processing module (3) is connected with the first input / output end of the MCU module (4), the second input / output end of the MCU module (4) is connected with the first input / output end of the storage module (6), the third output end of the MCU module (4) is connected with the second input end of the multi-channel signal selection module (2), the fourth output end of the MCU module (4) is connected with the input end of the display module (7); The multi-channel signal selection module (2) comprises A m-cuts-n-throw analog switches, and The temperature signal processing module (3) comprises B analog-to-digital converters. The number of cascade layers of the multi-channel signal selection module (2) The relationship between the analog switch and the analog-to-digital converter is The relationship between the number of temperature measurement channels c and the analog switch and the analog-to-digital converter is .
2. The multi-channel furnace temperature acquisition device based on the multi-layer cascaded analog switch circuit according to claim 1, characterized in that: The temperature information acquisition module (1) includes K-type thermocouple, electromagnetic shielding layer, ceramic shell and ground bus; The ceramic shell wraps the temperature measuring probe of the K-type thermocouple, the K-type thermocouple wraps the electromagnetic shielding layer, and the electromagnetic shielding layer is connected with the ground bus.
3. The multi-channel furnace temperature acquisition device based on the multi-layer cascaded analog switch circuit according to claim 1, characterized in that: The MCU module (4) is a Cortex-M3 processor with STM32F103 series ARM core.
4. The multi-channel furnace temperature acquisition device based on the multi-layer cascaded analog switch circuit according to claim 1, characterized in that: The power module (5) provides 5V voltage for the multi-channel signal selection module (2), the temperature signal processing module (3), the MCU module (4), the storage module (6) and the display module (7).
5. The multi-channel furnace temperature acquisition device based on the multi-layer cascaded analog switch circuit according to claim 1, characterized in that: The storage module (6) uses a high-speed TF card with a capacity of 32G.
6. The multi-channel furnace temperature acquisition device based on the multi-layer cascaded analog switch circuit according to claim 1, characterized in that: The display module (7) uses a 3.7-inch color LCD screen.
Citation Information
Patent Citations
Smelting temperature real-time measuring system suitable for high-activity metal smelting substances in course of vacuum induction smelting
CN101975621A
Signal acquisition system
CN102213956A
Furnace temperature meter
CN204422091U