Welcome to Peak Asic's L7 Hashboard repair guide! We specialize in providing expert Antminer hashboard repairs, but we understand that some of you might want to try repairing your devices yourself. To support your efforts, we've created this comprehensive guide to help you through the process. Follow the steps below, and feel free to reach out to us if you need professional assistance or would like to send in miners for repair.
I. Preparation for Maintenance: Platform, Tools, and Equipment
1. Platform Requirements:
- **Static repair workbench:** Ensure it is grounded.
- **Anti-static wristband:** Must be grounded.
2. Equipment Requirements:
- **Constant temperature soldering iron:** Set between 350°C and 380°C with a pointed tip for small components like chip resistors and capacitors.
- **Hot air gun and BGA rework station:** For chip/BGA disassembly and soldering.
- **Multimeter:** Fluke 17B+ recommended, with welded steel needles and heat-shrinkable sleeves for easy measurement.
- **Oscilloscope and network cable.**
3. Test Tool Requirements:
- **APW12 power supply:** APW12_14V-17V_V1.2 and power adapter cable for hash board power supply.
- **Test fixture:** Material number ZJ0001000001. Discharge resistors of 20 ohms, 100W or more should be installed on the power supply’s positive and negative poles.
4. Auxiliary Materials and Tools for Maintenance:
- **Solder paste (M705), flux, and cleaning solution:** Use anhydrous alcohol to clean flux residue after repairs.
- **Thermal gel (Fujipoly SPG-30B):** Apply on the chip surface after repairs.
- **Ball-planting steel mesh, solder-absorbing wire, and solder balls:** Recommended diameter is 0.4mm.
- **New chip soldering:** Pre-tin chip pins before soldering them onto the hash board, apply thermal gel evenly on the chip surface before securing the heat sink.
- **Serial port code scanner and serial port adapter board:** RS232/TTL adapter board 3.3V.
- **Self-made short-circuit probe:** Use pins to wire and solder, with heat-shrinkable sleeves to prevent short-circuiting between the probe and the small heat sink.
5. Common Spare Parts for Maintenance:
- **0402 Resistors:** (0R, 1K, 4.7K, 10K).
- **0402 Capacitors:** (0.1uF, 1uF).
II. Repair Requirements
1. Chip Replacement:
- Ensure no visible deformation of the PCB after replacing any components. Check for missing parts, open circuits, or short circuits around replaced components.
2. Personnel Expertise:
- Maintenance personnel should have a good understanding of electronics, more than one year of maintenance experience, and proficiency in BGA/QFN/LGA soldering techniques.
3. Post-Maintenance Testing:
- Test the hash board at least twice to ensure it passes both times.
- Verify the functionality of tools and test fixtures, ensuring correct parameters and versions of test software and fixtures.
4. Chip Testing:
- Perform chip tests before functional tests. Ensure small heat sinks are soldered correctly, and large heat sinks are installed with evenly applied thermal adhesive. Use full-speed fans for cooling.
5. Signal Measurement:
- Use four fans for heat dissipation and keep them at full speed during signal measurement.
6. Power Connection Order:
- Connect the negative copper wire first, then the positive copper wire, and finally the signal cable. Reverse the order during disassembly to avoid damaging U1 and U2 chips.
7. New Chip Soldering:
- Pre-tin chip pins before soldering to the PCBA. Apply thermal gel evenly on the chip surface before attaching the large heat sink.
III. Test Fixture Creation and Precautions
- Ensure the test fixture meets the cooling requirements of the hash board and facilitates signal measurement.
1. Part Number:
- Use ZJ0001000001 Test fixture and consider using the new digital display Antminer test fixture.
2. FPGA Update:
- Use the 7Z007 series test fixture SD card swipe program to update the FPGA of the fixture control board. Insert the SD card into the test fixture card slot, power on, and wait for the control board indicator lights to double flash at least 3 times.
3. Test SD Card Creation:
- For single-sided heat sink inspection chips, decompress the package to create the SD card. PT1 tests do not require a network cable or code scanner.
- PT2 tests require a code scanner and network cable for running the Patter test. Refer to the L7 test process document for details.
IV. Principle Overview
1. Working Structure of L7 Hash Board:
- Composed of 120 BM1489 chips divided into 24 domains, each with 5 ASIC chips. Working voltage of BM1489 chips is 0.6V. The 24th to 21st groups are powered by 19.6V from the boost circuit U13, outputting 1.8V and 0.8V. The 20th group LDO is powered by 14.4V, reducing domain voltage by 0.6V each domain back.
2. Boost Circuit:
- Converts 15V from the power supply to 19.6V.
3. Signal Direction:
- **CLK Signal:** Generated by Y1&Y2 25M crystal oscillator, Y1 provides for chips 01 to 60, Y2 for chips 61 to 120.
- **RST and CI Signals:** Flow from the IO port 3 pin (3.3V) into level conversion ICs U1-U3-U4, then from chip 01 to 120.
- **RX (RI, RO) Signal:** Flows from chip 120 to 01, back to the control board.
- **BO (BI, BO) Signal:** Flows from chip 01 to 120.
4. Antminer L7 Structure:
- Composed of 3 hash boards, 1 control board, APW12 power supply, and 4 cooling fans.
V. Common Fault Phenomena and Troubleshooting Steps for Hash Board
Phenomenon 1: Single-Board Test Detects 0 Chips (PT1/PT2 Station)
- **Step 1:** Check power supply output.
- **Step 2:** Check voltage domain output, should be around 0.6V.
- **Step 3:** Check PIC circuit and reprogram if necessary.
- **Step 4:** Check boost circuit output (should be 23V at C70).
- **Step 5:** Check each LDO output (1.8V or 0.8V).
- **Step 6:** Check chip signal outputs against expected voltage ranges.
Phenomenon 2: Single-Board Detection Lacks Chips (PT1/PT2 Station)
- **a)** If ASIC NG: (0), measure domain and boost circuit voltages, and use a short-circuit probe to test RO and 1V8 between chips.
- **b)** If one chip is found, use similar methods to check subsequent chips.
- **c)** If a fixed chip is reported, measure signal voltage normally.
Phenomenon 3: Single Board Pattern NG (PT2 Station)
- Replace the chip with the lowest reply rate in each domain based on fixture screen or log information.
Phenomenon 4: Incomplete Reply Rate (P:NG)
- Replace the two chips with the lowest reply rates to meet the standard.
Phenomenon 5: Sensor NG
- Check temperature sensor circuit, ensuring 3.3V power supply and normal SDA and SCL buses. PT2 test environment should be between 25℃ and 30℃.
VI. Control Board Problems and Solutions
1. Miner Does Not Work:
- Check voltage output points and replace corresponding ICs if necessary. Inspect DDR/CPU soldering and try updating the flash program.
2. Miner Cannot Find IP:
- Check network port, transformer T1, and CPU for proper soldering.
3. Miner Cannot Upgrade:
- Check network port, transformer T1, and CPU for proper soldering.
4. Miner Fails to Read Hash Board or Chain is Missing:
- Check cable connections, control board components, and wave soldering quality of header pins and resistances.
VII. Whole Miner Failure Phenomenon
1. Preliminary Test of Whole Machine:
- Check for assembly and control board process problems, such as IP detection issues, fan abnormalities, and chain detection issues. Repair based on monitoring interface and test LOG prompts.
2. Aging Test:
- **Fan Abnormality:** Check fan operation and connections.
- **Less Chain:** Inspect cable connections and test individual boards.
- **Abnormal Temperature:** Ensure the maximum PCB temperature does not exceed 90°C and inspect fan operation.
- **Chip Detection Issues:** Test individual boards with PT2.
- **Network Connection Issues:** Check the network connection.
- **Aging Test Status:** Monitor the status of the normal good miner.
VIII. Other Precautions
Maintenance Flow Chart:
1. **Routine Testing:**
- Visually inspect the hash board for deformation, scorching, or missing parts. Check for short circuits or open circuits and ensure voltage in each domain is around 0.6V.
2. **Chip Inspection:**
- Use a test fixture to inspect chips, determine fault location, and check chip test points and voltages.
3. **Signal Flow:**
- Identify unusual points of failure based on signal direction and power supply sequence.
4. **Re-Soldering:**
- Re-solder faulty chips with no-clean flux, heat the solder joints to a dissolved state, and promote re-tinning.
5. **Post-Repair Testing:**
- Test the hash board twice to confirm it is
OK. Record maintenance/analysis results.
I. Preparation for Maintenance: Platform, Tools, and Equipment
1. Platform Requirements:
- **Static repair workbench:** Ensure it is grounded.
- **Anti-static wristband:** Must be grounded.
2. Equipment Requirements:
- **Constant temperature soldering iron:** Set between 350°C and 380°C with a pointed tip for small components like chip resistors and capacitors.
- **Hot air gun and BGA rework station:** For chip/BGA disassembly and soldering.
- **Multimeter:** Fluke 17B+ recommended, with welded steel needles and heat-shrinkable sleeves for easy measurement.
- **Oscilloscope and network cable.**
3. Test Tool Requirements:
- **APW12 power supply:** APW12_14V-17V_V1.2 and power adapter cable for hash board power supply.
- **Test fixture:** Material number ZJ0001000001. Discharge resistors of 20 ohms, 100W or more should be installed on the power supply’s positive and negative poles.
4. Auxiliary Materials and Tools for Maintenance:
- **Solder paste (M705), flux, and cleaning solution:** Use anhydrous alcohol to clean flux residue after repairs.
- **Thermal gel (Fujipoly SPG-30B):** Apply on the chip surface after repairs.
- **Ball-planting steel mesh, solder-absorbing wire, and solder balls:** Recommended diameter is 0.4mm.
- **New chip soldering:** Pre-tin chip pins before soldering them onto the hash board, apply thermal gel evenly on the chip surface before securing the heat sink.
- **Serial port code scanner and serial port adapter board:** RS232/TTL adapter board 3.3V.
- **Self-made short-circuit probe:** Use pins to wire and solder, with heat-shrinkable sleeves to prevent short-circuiting between the probe and the small heat sink.
5. Common Spare Parts for Maintenance:
- **0402 Resistors:** (0R, 1K, 4.7K, 10K).
- **0402 Capacitors:** (0.1uF, 1uF).
II. Repair Requirements
1. Chip Replacement:
- Ensure no visible deformation of the PCB after replacing any components. Check for missing parts, open circuits, or short circuits around replaced components.
2. Personnel Expertise:
- Maintenance personnel should have a good understanding of electronics, more than one year of maintenance experience, and proficiency in BGA/QFN/LGA soldering techniques.
3. Post-Maintenance Testing:
- Test the hash board at least twice to ensure it passes both times.
- Verify the functionality of tools and test fixtures, ensuring correct parameters and versions of test software and fixtures.
4. Chip Testing:
- Perform chip tests before functional tests. Ensure small heat sinks are soldered correctly, and large heat sinks are installed with evenly applied thermal adhesive. Use full-speed fans for cooling.
5. Signal Measurement:
- Use four fans for heat dissipation and keep them at full speed during signal measurement.
6. Power Connection Order:
- Connect the negative copper wire first, then the positive copper wire, and finally the signal cable. Reverse the order during disassembly to avoid damaging U1 and U2 chips.
7. New Chip Soldering:
- Pre-tin chip pins before soldering to the PCBA. Apply thermal gel evenly on the chip surface before attaching the large heat sink.
III. Test Fixture Creation and Precautions
- Ensure the test fixture meets the cooling requirements of the hash board and facilitates signal measurement.
1. Part Number:
- Use ZJ0001000001 Test fixture and consider using the new digital display Antminer test fixture.
2. FPGA Update:
- Use the 7Z007 series test fixture SD card swipe program to update the FPGA of the fixture control board. Insert the SD card into the test fixture card slot, power on, and wait for the control board indicator lights to double flash at least 3 times.
3. Test SD Card Creation:
- For single-sided heat sink inspection chips, decompress the package to create the SD card. PT1 tests do not require a network cable or code scanner.
- PT2 tests require a code scanner and network cable for running the Patter test. Refer to the L7 test process document for details.
IV. Principle Overview
1. Working Structure of L7 Hash Board:
- Composed of 120 BM1489 chips divided into 24 domains, each with 5 ASIC chips. Working voltage of BM1489 chips is 0.6V. The 24th to 21st groups are powered by 19.6V from the boost circuit U13, outputting 1.8V and 0.8V. The 20th group LDO is powered by 14.4V, reducing domain voltage by 0.6V each domain back.
2. Boost Circuit:
- Converts 15V from the power supply to 19.6V.
3. Signal Direction:
- **CLK Signal:** Generated by Y1&Y2 25M crystal oscillator, Y1 provides for chips 01 to 60, Y2 for chips 61 to 120.
- **RST and CI Signals:** Flow from the IO port 3 pin (3.3V) into level conversion ICs U1-U3-U4, then from chip 01 to 120.
- **RX (RI, RO) Signal:** Flows from chip 120 to 01, back to the control board.
- **BO (BI, BO) Signal:** Flows from chip 01 to 120.
4. Antminer L7 Structure:
- Composed of 3 hash boards, 1 control board, APW12 power supply, and 4 cooling fans.
V. Common Fault Phenomena and Troubleshooting Steps for Hash Board
Phenomenon 1: Single-Board Test Detects 0 Chips (PT1/PT2 Station)
- **Step 1:** Check power supply output.
- **Step 2:** Check voltage domain output, should be around 0.6V.
- **Step 3:** Check PIC circuit and reprogram if necessary.
- **Step 4:** Check boost circuit output (should be 23V at C70).
- **Step 5:** Check each LDO output (1.8V or 0.8V).
- **Step 6:** Check chip signal outputs against expected voltage ranges.
Phenomenon 2: Single-Board Detection Lacks Chips (PT1/PT2 Station)
- **a)** If ASIC NG: (0), measure domain and boost circuit voltages, and use a short-circuit probe to test RO and 1V8 between chips.
- **b)** If one chip is found, use similar methods to check subsequent chips.
- **c)** If a fixed chip is reported, measure signal voltage normally.
Phenomenon 3: Single Board Pattern NG (PT2 Station)
- Replace the chip with the lowest reply rate in each domain based on fixture screen or log information.
Phenomenon 4: Incomplete Reply Rate (P:NG)
- Replace the two chips with the lowest reply rates to meet the standard.
Phenomenon 5: Sensor NG
- Check temperature sensor circuit, ensuring 3.3V power supply and normal SDA and SCL buses. PT2 test environment should be between 25℃ and 30℃.
VI. Control Board Problems and Solutions
1. Miner Does Not Work:
- Check voltage output points and replace corresponding ICs if necessary. Inspect DDR/CPU soldering and try updating the flash program.
2. Miner Cannot Find IP:
- Check network port, transformer T1, and CPU for proper soldering.
3. Miner Cannot Upgrade:
- Check network port, transformer T1, and CPU for proper soldering.
4. Miner Fails to Read Hash Board or Chain is Missing:
- Check cable connections, control board components, and wave soldering quality of header pins and resistances.
VII. Whole Miner Failure Phenomenon
1. Preliminary Test of Whole Machine:
- Check for assembly and control board process problems, such as IP detection issues, fan abnormalities, and chain detection issues. Repair based on monitoring interface and test LOG prompts.
2. Aging Test:
- **Fan Abnormality:** Check fan operation and connections.
- **Less Chain:** Inspect cable connections and test individual boards.
- **Abnormal Temperature:** Ensure the maximum PCB temperature does not exceed 90°C and inspect fan operation.
- **Chip Detection Issues:** Test individual boards with PT2.
- **Network Connection Issues:** Check the network connection.
- **Aging Test Status:** Monitor the status of the normal good miner.
VIII. Other Precautions
Maintenance Flow Chart:
1. **Routine Testing:**
- Visually inspect the hash board for deformation, scorching, or missing parts. Check for short circuits or open circuits and ensure voltage in each domain is around 0.6V.
2. **Chip Inspection:**
- Use a test fixture to inspect chips, determine fault location, and check chip test points and voltages.
3. **Signal Flow:**
- Identify unusual points of failure based on signal direction and power supply sequence.
4. **Re-Soldering:**
- Re-solder faulty chips with no-clean flux, heat the solder joints to a dissolved state, and promote re-tinning.
5. **Post-Repair Testing:**
- Test the hash board twice to confirm it is
OK. Record maintenance/analysis results.