Summary of common breakdowns of hard disk parts

1. Hard disk power supply: The power of the hard drive from the host's switching power supply, the voltage of four terminals are: Red is 5V, black for ground, yellow is positive 12V, through the linear power conversion circuit, to transform the normal work of the hard disk voltage. If there is a problem with the power supply circuit of the hard disk, it will directly cause the hard drive to work. Fault phenomenon is often shown as no power, hard disk detection, the disc does not turn, the head does not seek road and so on. The parts of the power supply circuit are: the wiring column of the socket, the filter capacitor, the diode, the transistor, the field effect tube, the inductance, the insurance resistor and so on.

2. Interface: interface is the transmission of data between the hard disk and the computer, the interface circuit such as failure may result in hard disk detection, garbled, parameter mistaken recognition and so on. Interface circuit often out of place is the interface chip or match with the crystal oscillator bad, the interface pins or false welding or dirty, interface resistance damage, some hard disk interface plastic damage caused manufacturers do not warranty.

3. Caching: Used to speed up hard disk data transmission, such as problems may cause hard disk is not recognized, garbled, into the operating system after the abnormal panic and so on.

4.BIOS: For storage and hard disk capacity, interface information, and so on, the hard drive all the workflow is related to the BIOS program, the power of the moment may cause the BIOS program loss or disorder. Abnormal BIOS can lead to hard disk recognition, unrecognized and other kinds of failure phenomenon.

5. Head chip: Mounted on the head assembly, used to enlarge the head signal, the head logic allocation, processing voice coil motor feedback signal, the chip problems may appear the head can not be properly found, the data can not be written to the disc, can not identify the hard disk, abnormal sound and other fault phenomena.

6. Front signal Processor: used to process the processing of the data signal from the head chip, the chip if there is a problem may not correctly identify the hard drive failure phenomenon.

7. Digital Signal Processor: Used to handle the data signal transmitted by the front signal handler, decode or receive the data signal from the computer, and encode the signal.

8. Motor Drive chip: used for drive spindle motor and voice coil motor. Now the hard drive because the speed is too high cause the chip calorific value is too large and damaged, according to incomplete statistics, about 70% of the hard drive circuit roadblocks are caused by the chip damage.

9. Platters: Used to store hard disk data, minor scratches can be corrected by the software according to a certain algorithm, serious scratch, data can not be restored.

10. Spindle motor: Used to drive the disc high-speed rotation, now most of the hard drive using liquid bearing motor, precision is very high, after a violent collision may make the gap becomes large, reading data becomes difficult, abnormal sound or can not detect the hard disk. The fault phenomenon requires special equipment to read the data inside.

11. Magnetic head: Used to read or write hard disk data, is easily damaged by severe collisions, resulting in the hard drive is not recognized. The hard disk is more likely to be damaged by a collision than the head.

12. Voice Coil Motor: Closed-loop control motor for the accurate positioning of the head on the track. The motor is less damaged.

13. Positioning clamp: Used to make the head to stay in the Kai-stop zone, IBM and other series of hard disk clips easily dislocation, leading to the head can not be normal search. In the absence of open maintenance conditions, can be a certain angle appropriate percussion hard disk, so that the clamp back to the correct position.

Attached: Hard drive motor drive chip resistance measurement method

Hard disk motor drive chip is the most vulnerable part of the hard drive circuit chip, about 70% of the hard drive circuit failure is caused by the chip damage. and whether the motor-driven chip in the end can be damaged by the chip around the pin to the ground resistance to the approximate judgment. The following table is a common hard disk motor drive chip each PIN to the ground reverse resistance table. Used to confirm that the motor drive chip is damaged. Data test using a 9205-type digital multimeter, Red pen grounding, black pen pointing to the measured pin.

For chips with only two pins on both sides, starting with the first pin in a counter-clockwise direction is represented by a number of digits, the first of which represents the first resistance, and the second is the resistance on the second side.

For chips with pins on all sides, starting from the first pin in the counterclockwise direction of the pins used in four-column numbers, where the first column represents the first side of the resistance, the second column indicates the second side of the Resistance, the third column represents the third side of the Resistance, the fourth column represents the four-side resistance.