What is High TG PCB?
In addition to basic FR-4 materials in PCB production, some projects need to use high TG materials, so what are high TG materials? High Tg is another name for a high-temperature PCB, meaning printed circuit boards designed to stand up to high-temperature extremes. A circuit board is defined as high Tg if its glass transition temperature (Tg) is higher than 170 degrees Celsius. The full name of TG used in PCB fabrication is glasstransitiontemperature, which stands for glass transition temperature. The Glass Transition Temperature (Tg) is one of the most important properties of any epoxy and is the temperature region where the polymer transitions from hard, glassy material to a soft, rubbery material. The circuit board must be flame-resistant, it cannot burn at a certain temperature, it can only soften. The temperature point at this time is called the glass transition temperature (Tg point), and this value is related to the dimensional stability of the PCB board. The higher the TG value, the better the temperature resistance of the PCB. When the temperature rises to a certain area with a high TgPCB, the substrate will change from a “glass state” to a “rubber state”, which is called the glass transition of the sheet (Tg). temperature.
The importance of high-TG PCBs.
High TG PCB’s high performance operation and high stability at high temperature make it a reasonable solution for high power density design. The higher the TG of the board, the higher the heat resistance, chemical resistance and mechanical stability of the electronic device.
High-TG PCB has good heat dissipation for multilayer PCB and HDI PCB. These PCBs generate more heat because the components in multilayer PCBs and HDI PCBs are more compact and the circuits are very dense. High TG PCB has good thermal control, which helps to ensure the reliability of the product during operation.
We all know that if electronic products often work for a long time, the heat generated during the working process will be transferred to other parts, which will ultimately affect the durability and performance of the product. For some electronic products with multiple functions but limited size and weight applications, high TG PCB will be a cost-effective method to improve thermal management efficiency.
What Is A DIP Package?
Dual in-line package (DIP) is the most common through-hole IC package in the PCB electronic component packaging process, abbreviated as DIP or DIL. DIP packages are typically melt-molded from an opaque epoxy resin with a lead frame supporting the device chip. And provide connecting pins extending vertically out of the rectangular plastic housing. Silver, gold or tin plating is optional around the parallel metal pins (pin headers) on both sides of the IC.
DIP packages can be mounted on a circuit board or inserted into a socket using through holes. DIPs are often referred to as DIPn, where n is the total number of pins. For example, a through-hole IC package with two rows of eight pins would be a DIP16. Common packages range from 3 to 64 or even 100. DIP derives a higher density package form – SDIP (Shrink DIP), which has six times the pin density of standard DIP.
The number of pins determines the overall size of the DIP package. The most common stitch counts are four, six, eight, ten, twelve, fourteen, sixteen, eighteen, twenty, twenty-eight, and forty, among others. The pins on the DIP IC have different pitches such as 0.5mm, 0.65mm, 1.27mm, and 2.54mm. Regular Standard Pitch – Ideal for loading into breadboards, veroboards and other prototype boards. Of course, there are also some special pitches in some special DIP package series.
Features Of DIP Package.
The dual in-line package is characterized by easy perforation soldering of printed circuit boards and good compatibility with circuit boards. However, due to the gradual high-density interconnection of electronic devices, the limited number of pins in the DIP package cannot achieve small-scale high-density integration. Now, DIP has slowly faded out of people’s field of vision.
The internationally accepted DIP package JEDEC standard has a pitch of 2.54 mm between two pins. The DIP package used in some Eastern European countries is slightly different from the JEDEC standard, and its pitch is metric 2.5mm. The distance between the two rows of pins depends on the number of pins. Other less common distances are: 1.78 mm, 7.62 mm, 15.24 mm, 10.16 mm or 22.86 mm.
Number of needles:
The number of pins in a DIP package is always an even number. Common DIP pin counts are 8, 14, 16, 18, 20, 24, 28, 32 or 40, 48. Of course, there are also 52- or 64-pin packages, which are the maximum pin counts commonly used in DIP packages today.
Orientation and Pin Numbers:
When the identification notch of the DIP component is facing up, the first pin on the upper left is pin 1, and the other pins in the same row are sorted in anti-clockwise order. Jumping to the opposite row of pins after going to the bottom is to sort from bottom to top.
Take the DIP18 integrated circuit as an example: when the identification notch is facing up, the pins on the left are 1-9 pins from top to bottom, and the pins on the right are 10-18 pins from bottom to top.