BM1370BC ASIC Chip Tin Stencil for Antminer S21Pro Hashboard

BM1370BC Tin Stencil – Antminer S21 Pro Hashboard ASIC Chip Repair

Achieving a reliable BGA reflow on the BM1370BC ASIC chip starts with even solder-ball placement — and that requires a purpose-built stencil. This tin stencil is laser-cut specifically for the BM1370BC pad array used on Antminer S21 Pro hash boards. The high-temperature aluminum alloy base resists warping during preheat, and the wear-resistant steel mesh maintains aperture accuracy across hundreds of chip replacements.

Why a Dedicated Stencil Matters for the BM1370BC

The BM1370BC's BGA pad pitch is tight enough that manual solder-paste application almost always produces bridges or voids. A stencil guarantees the correct paste volume on every pad, eliminating the two most common reflow failures: solder bridges between adjacent balls (causing short circuits that can damage the chip on power-up) and insufficient paste (creating open joints that appear as intermittent hash errors). For shops running S21 Pro repairs at volume, the stencil pays for itself after the first successful chip swap.

Stencilling Workflow

After removing the failed BM1370BC with a hot-air station and cleaning the PCB pads, place the stencil over the chip footprint and align it with the corner fiducials. Apply lead-free solder paste with a squeegee in a single smooth pass, then lift the stencil vertically to avoid smearing. Place the new BM1370BC chip, aligning its pin-1 marker with the PCB reference, and reflow using a BGA-profile hot-air station. After cooling, inspect under magnification and run a test-fixture scan to confirm the chip is hashing at full speed.

BM1370BC Tin Stencil Specifications

Related BM1370BC & S21 Pro Repair Tools

• BM1370BC Tin Tool Station – S21 Pro Hashboard
• BM1370BC ASIC Chip – S21 Pro / S21XP / S21 Hydro
• S21 Pro Thermal Paste Precision Application Tool
• BM1370 Series ASIC Chip Tester

Running S21 Pro chip replacements at scale? Contact us at contact@lys-sz.com for stencil and chip bundle pricing.

Worldwide shipping from our Shenzhen warehouse.