SOT-23-6 PCB Footprint: Dimensions, DFM, and Assembly Guide

SOT-23-6 is a gull wing package used for surface mount assembly, also seen labeled SOT-26, TSOT-23-6, SC-74 variants. A dependable footprint follows the exact orderable-device drawing rather than the family name: nominal body About 2.9 × 1.6 mm nominal, overall span About 2.8–3.0 mm lead span, seated height Typically 0.9–1.45 mm, pitch 0.95 mm, pin count 6, and exposed pad Normally none.

Use the exact six-lead drawing and pin table; do not derive it by filling the missing position of SOT-23-5.

Typical uses include dual transistors, small converters, ESD and analog ICs. SOT-23-6 is a family label with dimensional variants; the selected manufacturer's drawing is authoritative.

• Three evenly spaced leads per side make a symmetric outline, so reliable pin-one marking is more important than on SOT-23-5.
• Converter parts in this body can have hot switching nodes only one pitch from feedback or ground pins.

Follow the device reference layout for switching loops; the compact package does not make a long external inductor loop harmless.

• Place bypass parts against their actual pins and keep copper under sensitive nodes out of the switch-node field where the datasheet directs.

Hand assembly is rated moderate. Fluxed drag soldering or controlled reflow. Watch for fine bridges and rotating the footprint 180 degrees during library creation.

• Keep the pin-one marker visible after placement and consistent across copper, silk, and assembly drawing.
• Use balanced paste apertures across both rows to prevent rotation.
• Confirm that a proposed alternate is really SOT-23-6 rather than smaller SC-70-6 or a thin incompatible variant.

Inspection focus:

• AOI can see all six joints, but a pin-one rotation requires placement-data and functional checks.
• For converters, inspect the switch-node area and measure startup current before connecting the intended load.

Common mistakes:

• Copying a six-pin symbol from a different device and trusting matching package names.
• Routing feedback beside the switch node because both pins are physically adjacent.

1. Before approving SOT-23-6, compare the exact orderable-device drawing with the library item: body range (About 2.9 × 1.6 mm nominal), terminal or lead span (About 2.8–3.0 mm lead span), pitch (0.95 mm), pin count (6), height (Typically 0.9–1.45 mm), and exposed-pad definition (Normally none). Record the source drawing revision and every intentional courtyard, toe, heel, side, mask, or paste adjustment.
2. Treat the moderate hand-solder rating as a prototype-planning input, not proof of production yield. Review fine bridges and rotating the footprint 180 degrees during library creation with the assembler, confirm that fluxed drag soldering or controlled reflow is compatible with the build, and require the S1 connectivity gate plus relevant S2 geometry checks to pass against the released footprint and selected fabrication profile.

Manufacturing gate checks:

1. S1Pad count, numbering, and schematic parity. A symmetric body makes rotation and wrong pin maps difficult to spot visually.
2. S2Solder-mask web and pad opening. Six 0.95 mm-pitch pads must retain mask dams under the chosen process.
3. S2Courtyard and body clearance. The surrounding inductor or protection parts still need placement and rework clearance.