QFP (Plastic Quad Flat Package) chips have very small distances between pins and thin pins. This packaging form is generally used for large-scale or ultra large integrated circuits, with a pin count of generally over 100. Chips packaged in this form must be soldered to the motherboard using SMD (Surface Mount Device Technology). Chips installed using SMD do not need to be punched on the motherboard, as there are usually designed solder joints for corresponding pins on the surface of the motherboard. Align the pins of the chip with the corresponding solder joints to achieve soldering with the motherboard. The chip soldered in this way is difficult to disassemble without specialized tools.
The chips packaged in PFP (Plastic Flat Package) method are basically the same as those packaged in QFP method. The difference is that QFP is generally square, while PFP can be either square or rectangular.
QFP/PFP packaging has the following characteristics:
1. Suitable for SMD surface mount technology to install wiring on PCB circuit boards.
2. Suitable for high-frequency use.
3. Easy to operate and highly reliable.
The ratio between chip area and packaging area is relatively small.
The 80286, 80386, and some 486 motherboards in the Intel series CPUs use this packaging form.
PGA pin grid array packaging
The PGA (Pin Grid Array Package) chip packaging form has multiple square shaped pins inside and outside the chip, and each square shaped pin is arranged at a certain distance along the periphery of the chip. According to the number of pins, it can be enclosed in 2-5 circles. During installation, insert the chip into a dedicated PGA socket. In order to facilitate the installation and removal of CPUs, a CPU socket called ZIF has emerged since the 486 chip, specifically designed to meet the installation and removal requirements of PGA packaged CPUs.
ZIF (Zero Insertion Force Socket) refers to a socket with zero insertion and extraction force. Gently lift the wrench on this socket, and the CPU can be easily and effortlessly inserted into the socket. Then press the wrench back to its original position and use the squeezing force generated by the special structure of the socket itself to firmly contact the pins of the CPU with the socket, without any problem of poor contact. To disassemble the CPU chip, simply lift the wrench of the socket gently to release the pressure, and the CPU chip can be easily removed.
