描述

This Gel is special-purpose for Antminer S21

Structure of the whole machine:

The S21 is mainly composed of 3 hash boards, 1 control board, and 1 APW171215a power supply.(Control board, PSU In Stock）

The T21 is mainly composed of 3 hash boards, 1 control board, and 1 APW11A1216-1a power supply.(Control board, PSU In Stock）

Antminer S21 T21 hash board Maintenance platform/tool/equipment preparation requirements

1. Platform requirements:
Anti-static repair workbench (the workbench must be grounded), anti-static wrist strap and grounding.

2. Equipment requirements:
Thermostatic soldering iron (350-380 degrees Celsius), fine-tip soldering iron tip for soldering small SMD resistors and capacitors; hot air gun, BGA rework station for chip/BGA removal and soldering; multimeter, soldering steel needles covered with heat-shrink tubing for easy measurement (Fluke recommended); oscilloscope, ethernet cable (Requirements: for Internet connection, stable network).

3. Repair test tools requirements:
S21 power supply uses APW171215a, 12V-15V, V1.3, safety regulations (calibration). Or use other power supplies in the BOM and power adapter cables (DIY: use thick copper wires for the positive and negative poles to connect the power supply and the hash board. It is recommended to use 4AWG copper wires with a length of less than 60cm, only for PT1 and repair testing) used to power hash boards.

The fixture uses a V2.1 or V2.3 control board (material number ZJ0001000004). The positive and negative poles of the test fixture’s power supply need to be installed with discharge resistors. Use cement resistors of 20 ohms and above 100W. When using the 19 series universal test fixture for the first time, need to swipe the fixture B047 version (refer to the S21 test guidance document for details).

T21 PT3 test power supply APW11A1216-1a, 12V-16V, V1.1, safety regulations (calibration), PT1 can use conventional 1215 PSU.

(Control board, Test fixture In Stock）

4. Repair auxiliary materials/tools requirements:

Solder paste M705, flux, cleaning solution with anhydrous alcohol (cleaning solution is used to clean flux residues after repair); thermal gel used to apply on the chip surface after repair; tin tool stencil (BM1368 LGA 6mm * 8mm chip size), desoldering wire; solder balls (recommended diameter 0.4mm); when replacing a new chip, solder paste must be applied to the chip pins before soldering onto the hash board, apply thermal gel evenly on the chip surface before attaching the large heatsink.

( thermal gel, chip , tin tool stencil In Stock）

5. Common spare parts for repair:

SMD resistor 33 ohms, ±1%, 1/20W, R0201 (0603);
SMD resistor 10K, ±1%, 1/16W, 0402;
SMD resistor 0 ohms, ±5%, 1/16W, 0402;
SMD ceramic capacitor 1uF, +/-10%, 16V, X5R, 0402;
SMD ceramic capacitor 1uF, 6.3V, 20%, X5R, C0201 (0603);
SMD ceramic capacitor 22uF, +/-20%, 6.3V, X5R, 0603.

Repair requirements:

1. When replacing chips, pay attention to the operation techniques. After replacing any components, ensure there is no visible deformation of the PCB. Check for missing parts, open circuits, or short circuits around the replaced components.
2. Repair personnel must have certain electronic knowledge, at least one year of repair experience, and be proficient in BGA/QFN/LGA soldering techniques.
3. After repair, the hash board must be tested at least twice with both results being OK to pass. Each work order has a corresponding number of hash board SNs, and each board must be unique.
4. During repair testing, SNs must not be cross-scanned or reused. Check if the tools and testing fixtures are working properly. Ensure the repair The workstation’s test software parameters and the version of the test fixture are correct.
5. For testing after replacing chips, first perform a chip detection test. If it passes, proceed with the PT3 sweep function test. Ensure the heatsink assembly is properly installed for functional testing. Apply thermal gel evenly on the chip surface when installing the heatsink, and connect the fan to the test fixture for controlled testing.
6. Without fan cooling or continuous PT1 testing, the chip may overheat and damage the board.
7. When measuring signals and voltages with the heatsink attached, use a fan to blow air on the TOP side for measurement.
8. When replacing a new chip, use a tin stencil to apply solder paste to the chip pins. Ensure the chip is pre-tinned before soldering it onto the PCBA for repair.
9. All fixtures at the repair end must use Test_Mode and scan mode for testing. After the test passes, the production end will start from the first test station, proceed with normal machine assembly and aging (following the same level assembly).
10. After the PCBA with The removed heatsink is repaired and confirmed OK, be sure to reapply thermal paste to the heatsink before reinstallation and flow line testing (otherwise, the whole machine may not operate properly).