Antminer APW8 - User Manual

APW8 Power Supply Maintenance Guide
1
Instructions for Power Supply Maintenance
Version date: 2010.7.23
File Category: Maintenance Guide
Content of this Volume: It mainly describes the troubleshooting of various faults of the power
supply APW8, and how to use the test tool for accurate positioning.
※ The copyright of this article belongs to Bitmain. The article shall solely be reprinted, extracted or used in
any other ways with the permission of the copyright owner. Please contact Bitmain official customer service if
there is any need of reprinting or quoting.
I. Requirements on the Maintenance Platform
1. The constant temperature soldering iron above 80W (soldering temperature: 300-350°C). The tip
soldering iron head is used for soldering chip resistors and capacitors. The blade type soldering iron
head is used for soldering and replacement of plug-in components (soldering temperature: 380-
420°C)
2. The thermal chimney is used for chip disassembly and soldering, be careful not to heat for a long
time to avoid PCB foaming (soldering temperature: 260°C ±2 °C).
3. The AC controllable power supply voltage regulator (output 200-250V, can limit 0-20A current)
is used for APW8 power-on inspection. If there is no such condition, a 100W ordinary light bulb
can also be strung on the AC fire line with mains. Be careful.
4. For electronic load (power 2KW, meet the voltage 0-50V), if there is no such condition, a
resistive load that matches the APW8 can also be made.
5. The multimeter, suction gun, tweezers, V9-1.2 test jig and special power test card firmware (if
there is condition, an oscilloscope can be configured).
6. Flux, lead-free tin wire, water for cleaning panel with anhydrous alcohol; water for cleaning
panel is used to clean flux residue and appearance after maintenance.
7. Thermally conductive silicone grease (2500) is used to repair the thermal conduction between the
MOS and the cooling fin, thermal conductive silicone (704 silica gel) is used for fixing and
covering the glue damage at the original after the repair of the PCBA components
II. Requirements on Maintenance Operations
1. The maintenance personnel must have certain electronic knowledge, more than one year of
maintenance experience, and a certain understanding of the working principle of switching power
supply, and well master the soldering technology.

Summary

I. Requirements on the Maintenance Platform

1. The constant temperature soldering iron above 80 W (soldering temperature: 300-350°C). The tip soldering iron head is used for soldering chip resistors and capacitors. The blade type soldering iron head is used for soldering and replacement of plug-in components (soldering temperature: 380-420°C)

Specifies soldering iron requirements and temperatures for different component types.

2. The thermal chimney is used for chip disassembly and soldering, be careful not to heat for a long time to avoid PCB foaming (soldering temperature: 260°C ±2 °C).

Describes the thermal chimney for chip soldering and cautions about overheating.

3. The AC controllable power supply voltage regulator (output 200-250 V, can limit 0-20 A current) is used for APW8 power-on inspection. If there is no such condition, a 100 W ordinary light bulb can also be strung on the AC fire line with mains. Be careful.

Details the use of AC controllable power supply for inspection.

4. For electronic load (power 2 KW, meet the voltage 0-50 V), if there is no such condition, a resistive load that matches the APW8 can also be made.

Outlines the requirement for an electronic load or suitable resistive load.

5. The multimeter, suction gun, tweezers, V9-1.2 test jig and special power test card firmware (if there is condition, an oscilloscope can be configured).

Lists essential tools and testing equipment for maintenance.

6. Flux, lead-free tin wire, water for cleaning panel with anhydrous alcohol; water for cleaning panel is used to clean flux residue and appearance after maintenance.

Lists consumables like flux, tin wire, and cleaning agents.

7. Thermally conductive silicone grease (2500) is used to repair the thermal conduction between the MOS and the cooling fin, thermal conductive silicone (704 silica gel) is used for fixing and covering the glue damage at the original after the repair of the PCBA components

Specifies thermal conductive materials for heat dissipation and component fixing.

II. Requirements on Maintenance Operations

1. The maintenance personnel must have certain electronic knowledge, more than one year of maintenance experience, and a certain understanding of the working principle of switching power supply, and well master the soldering technology.

Defines qualifications and experience for maintenance personnel.

2. Before the product is opened and the PCBA panel is repaired, the large capacitor must be discharged, and the voltage must be measured with a multimeter (less than 5 V discharge), and then the soldering operation can be performed! Be sure to confirm to avoid electric shock.

Safety procedure for discharging capacitors before opening and soldering.

3. Pay attention to the working method when judging the circuit components. After replacing any device, the PCB panel has no obvious deformation, the soldering of bonding pad is reliable, and the replacement parts and the surrounding area have no problem such as insufficient parts, open circuit or short circuit.

Guidance on component judgment, soldering reliability, and checking for shorts/opens.

4. After replacing the key components, the main circuit shall have no short circuit and other obvious abnormalities before the AC voltage test, otherwise there is a hidden danger of explosion.

Pre-test caution for key component replacement to avoid explosion risks.

5. It needs AC220 V voltage to judge the circuit signal; pay attention to operational protection.

Notes on using AC220V for circuit judgment and operational protection.

III. The Principle and Structure of the Power Supply

1. Principle overview

Provides a general overview of the power supply's principle.

1.1 APW8 consists of 1 large panel, 2 fans and the upper and lower enclosures. The normal input AC220 V has two DC output voltages, which are SB 12 V respectively. The main voltage

Describes the physical composition and basic voltage outputs of APW8.

1.2 Performance characteristics and scope of use: S15, T15 with APW8 power supply 16.32 V-20.04 V as follows:

Details performance specs and usage scenarios for APW8.

1.3 Appearance of APW8 Power Supply

Describes the physical appearance of the APW8 power supply.

1.4 Parameters of APW8 Power Supply:

OUT1

Details parameters for the primary adjustable voltage output.

OUT2

Details parameters for the secondary fixed 12V output.

2. Maintenance ideas and cases of common faults

2.1 Block diagram for power basic principle

Presents a block diagram illustrating the power supply's basic operational principle.

2.2 Power PCBA board layout

2.21 AC inputs EMI to PFC circuit schematic, focus on measuring whether F1 insurance, U2 rectifier bridge, Q4, D7, D5, D6 are damaged.

2.22 12 V auxiliary circuit principle, focus on measuring whether voltage detection starts resistor R33, 47 K and connecting with HV to D1, D2, and whether Q5, D8, D9, T1 is damaged.

2.23 The main control PWM drive circuit, PIC control voltage regulation schematic diagram, focus on the main IC VCC power supply and drive transformer.

2.24 Main switch MOS and transformer conversion buck synchronous rectification DC filter output circuit, focus on the main switch MOS Q14; Q15; Q6; Q16, the output rectifier side positive and negative have no short circuit.

2.25 Location of A side of SMD patch and B side of plug-in

2.3 Maintenance steps

2.31. Check whether the appearance of the power supply is seriously damaged or deformed, and whether the DC fan and the AC socket are damaged.

Initial visual inspection for physical damage to the power supply and fan.

2.32. Power on AC220 V, check whether the fan is rotating normally, and use the multimeter to measure whether the output J6 terminals voltage is 12 V (12.1 V-12.50) to eliminate measuring error

Checks fan operation and measures output voltage at J6 terminal.

2.33. Open the enclosure to check whether the components and solder surface have sparking phenomenon (focus on whether the R33 resistor is damaged), use a multimeter to detect whether the AC input terminals F1 fuse has open circuit, whether the U2 rectifier bridge; PFC MOS Q1; D7; D5; D6 have short circuit, whether the PWM circuits main switches MOS Q6; Q14; Q15; Q16 and output patches MOS Q17; Q18; Q19; Q20 have short circuit; if there is a short circuit, the component position should be checked and replaced, pay attention to the circuit resistance around bad bit MOS tube; the transistor may be damaged and needs to be replaced.

Inspects for sparking, checks AC fuse, rectifier bridge, PFC MOS, and PWM MOS for shorts.

2.34. Detect whether the auxiliary 12 V circuits U5; T1; Q5; D11 have short circuit or open circuit, and whether the surrounding components are burned, etc., replace if necessary.

Checks auxiliary 12V circuits for shorts, opens, or burn marks.

2.35. If there is no abnormality in the above locations, the F1 fuse path is normal. After the AC is powered on, the DC fan rotates (if there is no rotation, check whether the fan socket has voltage of 12 V, if the voltage is normal, replace the fan); the output terminal J6 has 12 V voltage, measure whether there is DC370 V-380 V at both ends of PFC large capacitor C16 or C17, otherwise check whether U1, pin 7 V VCC power supply has 12 V or judge material damage and replace, if there is no abnormality, it needs to detect PWM circuit U9; U10; U11; whether supply VCC has 12 V voltage or judge material damage and replace, and whether the T4 drive transformer is damaged.

Checks PFC capacitor voltage, VCC power supply, and PWM circuit for issues.

2.36, other bad needs to be further analyzed and judged according to the skills of maintenance personnel,

Notes that further analysis depends on technician skill for other faults.

(一)测试设备:功率计 万用表 电子负载 或者其他同类型自动测试仪器。(DC 输出正常时,如没有负载也可以用带矿机测试)

(二)测试连接图如下:

TEST11 与 TEST7 负极万用表量测 VCC 12-13 V: TEST11 and TEST7 negative multimeters measure VCC 12-13 V

2.41 Diagram for S15 control panel V1.2 and APW8 power PIC port connection test, label 1 is the dedicated card test firmware, 2 is the DC voltage debugging high-low conversion button, 3 is the PIC communication port, 4 is the control panel socket, 5 is 12 V power supply; note that yellow indicates positive and black indicates negative. Note: After the general power supply defective products are repaired, the power supply only needs to be short connected with the PIC communication J15 port EN-GND pin, and if there is voltage output 16 V, it is normal, and the following single test for the control panel is not requried (when the PIC single chip is damaged, or when the firmware is abnormal, it needs to test a small panel before re-burning), and the corresponding mining machine test can be directly installed.

2.5 Simple judgment and maintenance of common faults of mine power supply

1 The fan does not run, there is no 12 V output

Fault: Fan not running, no 12V output. Cause: AC side abnormal. Solution: Check AC input and plugs.

2 The fan runs normally, there is no 12 V output

Fault: Fan runs, no 12V output. Cause: Low grid voltage, protection. Solution: Check voltage, short circuit/overload.

3 After the power supply stops output for a few seconds, it resumes normal operation. After a few minutes of continuous operation, it stops outputting again.

Fault: Intermittent output stops. Cause: Over-temperature protection. Solution: Check fan, cooling, dust, ambient temp.

4 Output is normal, the fan does not work

5 The normally working power supply suddenly has no output and will not start again

2.6 After the power supply maintenance test is normal, it is required to operate normally for 2 hours with the rated load of 80% (80 A) or more before it can be used by the client.

Antminer APW8 Specifications

General

Model	APW8
Input Voltage	200-240V AC
Rated Power	1800W
Output Power	1600W
Input Current	10A
Frequency	50/60Hz
Output Voltage	12V
Cooling	Fan
Operating Temperature	0°C to 40°C