Maintaining an Antminer S19 can be a daunting task if you don’t know what to look for. Knowing the basic steps of maintenance and troubleshooting is essential in keeping your miner running smoothly and efficiently. In this guide, we will cover the basics of Antminer S19 maintenance, from routine inspections to testing hash boards and replacing faulty chips. We will also provide tips on how to use Putty software to diagnose problems with the NONCE response status and domain voltage levels. With this guide, you’ll have all the information needed to keep your Antminer S19 running at optimal performance.
Preparation and Maintenance Guidelines
It’s essential to take the time to properly prepare and maintain components before, during, and after installation. This includes applying thermal gel for better heat transfer, forming air ducts for better airflow, connecting power supplies in the correct sequence, fixing chips to prevent overheating, and ensuring test fixtures meet production requirements. Additionally, these guidelines should also include instructions on cleaning components with approved solvents such as isopropyl alcohol or distilled water, as well as how to store components away from extreme temperatures and humidity levels safely. Finally, regularly scheduled maintenance checks should be carried out every few months or at least annually to guarantee the proper functioning of all parts within the system.
Preparation Requirements for Repair Platform, Tools, and Equipment
I. Platform Requirements
- To perform maintenance work, an anti-static maintenance workbench is required. It should be grounded, and an anti-static wristband and grounding are necessary.
II. Equipment Requirements
- Constant temperature soldering iron (350°C-380°C) with a pointed tip for soldering small patches such as chip resistors and capacitors.
- Hot air guns and BGA rework stations are used for chip / BGA disassembly and welding.
- Multimeter with welded steel pins and heat-shrinkable sleeves for easy measurement. The recommended model is the Fluke 15b+ multimeter.
- Oscilloscope. The recommended model is UTD2102CEX+. A network cable is required for an internet connection and a stable network.
III. Test Tool Requirements
- ARC Antminer Hashboard Tester
- Lab PSU 10-30V / 1-15A
- APW12 power supply: AP12_12V-15V_V1.2 and power adapter cable. It is recommended to use thick copper wire for the positive and negative poles of the power supply to connect the power supply and the power board and only limited to PT1 and maintenance test use.
- Use the test fixture of the V2.3 control board (test fixture material number ZJ0001000001). The positive and negative poles of the test jig need to be installed with discharge resistors. Using a cement resistance of 20 ohms and 100W or more is recommended.
IV. Maintenance Auxiliary Materials/Tools Requirements
- Solder Paste 138°C, flux, Mechanic lead-free circuit board cleaner, and anhydrous alcohol.
- Mechanic lead-free circuit board cleaner cleans up the flux residue after maintenance.
- Thermally conductive gel is used to apply to the chip surface after repair.
- Ball-planting steel mesh, desoldering wick, and solder balls (the recommended ball diameter is 0.4mm).
- When replacing a new chip, it is necessary to tin the chip pins and then solder them to the hash board. Apply thermally conductive gel evenly on the chip’s surface, then lock the heatsink.
- Serial port code scanner.
- Serial port adapter board RS232 to TTL adapter board 3.3V.
- Self-made short-circuit probe (use the pins for wiring and welding and heat the shrinkable sleeve to prevent short-circuit between the probe and the small heatsink).
V. Common Maintenance Spare Material Requirements
- 0402 resistor (0R, 10K, 4.7K,)
- 0402 capacitor (0.1uF, 1uF)
- When replacing a chip, pay attention to the operation method. After replacing any component, check that the PCB board has no obvious deformation. Check the replacement and surrounding parts for missing, open, and short circuits.
- Maintenance personnel must have electronic knowledge, at least one year of maintenance experience, and proficiency in BGA/QFN/LGA packaging and welding technology.
- After repair, the hashboard must be tested more than twice, and all tests must pass.
- Check the tools to ensure that the test fixture can work typically. Determine the parameters of the maintenance station test software, the version of the test jig, and other related parameters.
- To test repairing and replacing the chip, test the chip first and then do the functional test after it passes. The functional test must ensure that the small heatsink is welded correctly, the large heat sink is installed, and the thermal adhesive gel is applied evenly. Two hash boards should be placed simultaneously to form an air duct when using the chassis to dissipate heat. For single-sided testing in production, the air duct must also be formed.
- When measuring the signal, use fans to dissipate heat and ensure the fans are at full speed.
- When powering on the hashboard, connect the negative copper cord of the power supply first, then the positive copper cord of the power supply, and finally, insert the signal cable.
- When disassembling, reverse the order of installation. First, remove the signal cable, then pull the positive copper cord of the power supply, and finally, remove the negative copper cord. If you do not follow this order, it may cause damage to U1 and U2.
- Before testing the pattern, the repaired hashboard must cool down before testing; otherwise, it will lead to testing NG.
- Pre-tin the chip pins with solder paste to replace a new chip and then solder them to the PCB for repair.
Overview of Antminer S19 Components
S19 Hashboard Structure
The S19 hash board is made up of 76 BM1398 chips, which are divided into 38 groups (domains). Each group consists of 2 ICs, and the operating voltage of the BM1398 chip used in the S19 hash board is 0.36V. For the 38th, 37th, 36th, 35th, 34th, 33rd, and 32nd groups (a total of 7 groups), LDO is powered by the 19V output from the boost circuit U9 and outputs 1.8V. The 30th group to the 1st group are supplied by VDD13.64V through the LDO to provide 1.8V, and the voltage of each domain is reduced by 0.36V. All 0.8V is provided by the 1.8V output of this domain via LDO.
S19 Hashboard Boost Circuit
The boost circuit transfers the 14V power supplied by the power supply to 19V
Signal Trend of S19 Chip
The S19 chip has several signal trends:
- The CLK (XIN) signal is generated by Y1 25M oscillator and transmitted from chip 01 to chip 76, with a voltage of 0.7V-1.3V.
- The TX (CI, CO) signal is transmitted from IO port 7 pin (3.3V) into IC U2 through level conversion, and then transmitted from chip 01 to chip 76. The voltage is 0V when the IO signal is not inserted, and the voltage is 1.8V during operation.
- The RX (RI, RO) signal is transmitted from chip 76 to chip 01, returns to the signal cable terminal pin 8 through U1, and then returns to the control board. The voltage is 0.3V when the IO signal is not inserted, and the voltage will be 1.8V during computing.
- The BO (BI, BO) signal is transmitted from chip 01 to chip 76, with a multimeter measurement value of 0V.
- The RST signal is transmitted from pin 3 of the IO port, and then from chip 01 to chip 76. If no IO signal is inserted and the equipment is in standby, the voltage is 0V, and 1.8V when computing.
Whole Miner Architecture:
The whole miner consists of 3 hash boards, 1 control board, APW12 power supply, and 4 cooling fans.
Identifying Common Issues with Hashboards and Troubleshooting Procedures
Phenomenon 1: The detection chip on a single hash board test shows 0
The hash board is an important component of a cryptocurrency mining machine. If it is not functioning properly, it can cause serious problems. This article aims to provide troubleshooting steps for common faults related to the hash board.
Check the power output of the hashboard
- Check the power output of the hashboard.
- If the power output is abnormal, troubleshoot the issue using the following steps.
- Check the input voltage of the hash board and ensure that it is normal.
- Check the input voltage of the power module and ensure that it is normal.
- Check whether the input voltage is outputting from the power module.
- Check the MOS tube’s resistance and ensure it is not short-circuited.
- If the MOS tube is short-circuited, replace it with a new one.
- Check the output voltage of the power module and ensure that it is normal.
- Check the output voltage of the hash board and ensure that it is normal.
- If the voltage is abnormal, troubleshoot the issue using the next step.