Circuit integration in system-on-chip (SoC) drives today's embedded system design, and people want to integrate complex, flexible (programmable and configurable) analog, digital, and processing engines onto a single chip. This trend allows the SOC and MCU to integrate a variety of complex and advanced analog functions. These flexible analog circuits not only allow us to configure each module at design time, but also dynamically reconfigure the module functionality itself while the system is running. This versatile analog function can be implemented using a common switched capacitor (SC) network and some analog logic built into modern SoCs and MCUs. This article will explain how we use SC networks to implement various analog functions and their practical use in real-world applications. In addition, this article will also explain the principle and application of the SC analog module, including its functions, including mixers, mixers, filters, integrators, adders, subtractors, DACs, programmable gain amplifiers, and comparisons. , sample holders, and more.
Intelligent simulation
Analog circuit ecosystems require resistors, capacitors, and other analog blocks such as op amps, buffers, comparators, and basic analog logic. Since the fabrication of capacitors on integrated circuits is easier and more cost-effective, techniques for using switched capacitor analog resistors have been derived. These switched capacitors control the charge transfer between the capacitors with the precise timing of the switch (see Figure 1). Built-in clock/timing control allows the analog function to change in real time. These modules are sometimes referred to as Universal Simulation Modules (UABs).
Figure 1: Universal Analog Module (UAB)
The UAB consists of two fully symmetrical half-circuits that can be configured as one pseudo differential or two single-ended functions. Each half circuit is equipped with control logic for autonomous operation. Figure 2 shows a simplified UAB diagram. UAB's highly flexible conversion and continuous routing architecture enables complex analog functions such as analog filters.
Figure 2: Simplified UAB
Principle of charge transfer
Charge transfer refers to the controlled charge movement between voltage nodes. Figure 3 shows the charge transfer in the resistor and switched capacitor.
Figure 3: Simplified UAB
Â
In the resistor, the current (i) is formed by the potential difference across the resistor (R). The current flows from a voltage potential (V) through the resistor R to ground. Follow the following equation:
i = V / R
In a switched capacitor, current (i) is formed by charging a capacitor (C) at a high potential node and discharging it to a low potential node. When the Φ1 switch is closed and the Φ2 s switch is open, the capacitor C is fully charged. The stored charge is: q=CV
When the Φ1 switch is turned on and the Φ2 switch is closed, all of the stored charge moves to the ground node, moving a certain amount of charge during each switching cycle. If the control frequency of the switch is fs, the amount of charge also moves at that frequency. The repeated movement of the charge produces a current that follows the equation:
i = q/t = fsq = fsCV
Unlike resistors, the current in the switched capacitor does not move continuously. By comparing the above two current equations, we will find that if they have the same voltage drop current ratio, they are equivalent to resistors. Therefore, we can use a parallel switched capacitor series resistor.
V/i = R = 1/fsC
The equivalent resistance is inversely proportional to the switching frequency and capacitance. The relative value of the resistor can be easily changed by changing the switching frequency. A higher C value means a larger current and a smaller equivalent resistance. Similarly, a higher switching frequency (fs) means a larger current and a smaller equivalent resistance. The Φ1 and Φ2 switches must meet the timing requirements to produce the above results, including:
1) Do not turn off both switches at the same time;
2) Turn on the other switch before turning off a switch;
3) Select the maximum switching frequency so that C is fully charged and discharged during the cycle.
This switched capacitor forms a UAB with the operational amplifier and comparator. This way developers can integrate multiple simulation functions. This article explains one such analog feature - VDAC.
Implementation of VDAC Implementation VDAC:
VDAC is a digital to analog converter circuit that converts a digital input to an equivalent analog voltage. VDAC is at the heart of many control systems and determines the performance and accuracy of the system. The accuracy of the VDAC output voltage ultimately depends on its reference voltage. VDACs have many applications, such as programmable voltage generators, which provide sensor bias and compensation voltages, comparator voltage references, or dynamic output waveforms.
The UAB switched capacitor topology of the VDAC circuit is shown in Figure 3. Due to the discrete time nature of the switched capacitor module, the switched capacitor samples and buffers the data for continuous output. This module supports working in the MCU's working and sleep modes.
This topology brings flexibility to the VDAC functionality. The dynamic Vout range is determined by the Vref value at one end and the Vagnd value at the other end. This allows the user to set the dynamic Vout range by providing Vref and Vagnd through an external circuit. In addition, the gain setting selects the output range as Vagnd+Vref, Vagnd+2Vref or Vagnd+4Vref, thus ensuring the full range between Vssa and Vdda. This VDAC has a 13-bit input with an input range from -4096 to +4095. These values ​​can be written directly to the corresponding registers to take effect.
Figure 3: VDAC based on switched capacitor topology
Â
The VDAC in the analog coprocessor also supports a multiply mode, in which the VDAC output voltage is multiplied by the analog input signal to form a product output. Multiplying DACs (MDACs) are ideal for fixed reference applications where users want to generate waveforms from a fixed DC voltage. In addition, these MDACs are also suitable for a variety of reference applications where users wish to digitally convert AC or any reference voltage.
VDAC IDE configuration:
Despite the extreme flexibility and programmability of MCUs, developers are concerned that many configuration registers and tuning modules will work in order to accommodate their application design. The PSoC Creator tool supports analog coprocessors that allow users to easily configure these features. PSoC Creator is a free Windows-based integrated development environment (IDE) that enables parallel hardware and firmware design systems. The tool's design environment is similar to LEGO bricks, and users can place them on the circuit diagram by double-clicking on the components and configuring their functions. Figure 4 shows the VDAC component configuration tools in PSoC Creator, which can shorten the design cycle.
Figure 4: VDAC Component Configuration Tool in PSoC Creator
Â
PCD Inserts
PCD Inserts
OPT Cutting Tools Co., Ltd specialize in offering a comprehensive gamut of PCD diamond inserts, Some of our major product include PCD milling inserts and PCD turning inserts. Then, how to identify the different of them?
Turning is machining that is generally conducted on a lathe. To make it easier to comprehend turning, imagine the machining of a car shaft for example. The workpiece is held by both ends and rotated. Then a tool on a tool post or, if manual, held by hand is moved into the workpiece to carry out the machining.
Milling is opposite to that of turning.(major product: pcd inserts PCD cutting inserts PCD Milling Inserts PCD Grooving Inserts) When milling the workpiece is stationary and the tool is rotated. As the tool rotates one or more of the cutting edges engages with the workpiece and removes material. Therefore due to the action of the cutting edges coming into and out of contact with the workpiece the machining is interrupted machining. As the cutting edges engage and disengage with the workpiece the cutting edges are subjected to severe thermal shock. This is due to the rapid temperatures increase due to friction during the cut and rapid cooling as this cutting edge disengages from the workpiece. Therefore, to enable and achieve highefficiency machining, cutting tool manufacturers strive to improve and develop tool materials and cutting edge geometries. For milling, it is important to select a tool grade material that can withstand severe working conditions and a cutting edge geometry that can maximize the performance of the cutter.
Generally, PCD inserts are identified by different geometry by using letters of the alphabet. A wide range of geometries are listed as standard, Here we present some of PCD diamond inserts which widely used.
PRODUCT DETAIL:
product catagory :
PRODUCTING PROGRESS:
PAYMENT AND DELIVERY:
PRODUCT EQUIPMENT :
ABOUT US :
We are specialize in manufacturing PCD diamond tools and Carbide tools. Our major product inclulde PCD inserts, PCD Reamers , PCD End Mills, PCD Taps, Cabide Inserts,Carbide Drills, Carbide Reams, Taps etc.,
we also offered customized cutting tools per drawings, and provide package according to customer requirements. We manufacture a series range of cutting tools for machining of Cast iron, Aluminium alloy and Non-Ferros metal, it is widely used in all major sectors like Automobiles, Engineering, Aerospace, Aviation and 3C industry. Premium quality of raw material is used in the production and strict examination during processing with advanced equipment, so our client are satisfied with our reliable quality and on-time delivery.
Our best selling of cutting tools include PCD Inserts, PCD End Mill, PCD Ball Nose Mill, PCD Reamer, Carbide Taps , Carbide End Mill, Special Form Cutter and many more. For these years we have been made a large forward in the technologies of manufacturing cutting tools. With high quality on performance and price, our product sells well both on domestic and overseas market. And we will always focus on the quality and best service, to make long business relationship.
quanlity control:
We have dedicated team of quality control and precise equipment to keep good and stable performance for our products and processing services.
Chip Breaker,PCD Indexable Inserts,Diamond Blade,PCD Chipbreaker Groove Blade
OPT Cutting Tools Co., Ltd. , https://www.optdiamondtoolss.com