This part is an ARM JTAG/SWD 10-pin 0.05 in / 1.27 mm debug connector footprint/symbol. It is not an active electronic device; it is a compact board connector used to connect an external programmer/debugger to an ARM microcontroller.
Key purpose:
Provides access to SWD and/or JTAG debug signals.
Lets tools such as ST-LINK, J-Link, CMSIS-DAP, or other ARM debuggers program firmware, halt/run the CPU, set breakpoints, inspect memory, and sometimes reset the target board.
The project shows 9 pads for a 10-position connector because the standard ARM Cortex 10-pin header commonly has pin 7 omitted/keyed for polarization.
Typical pin functions:
VTref, pin 1: Target voltage reference. The debugger senses the target board’s I/O voltage here, e.g. 1.8 V, 3.3 V, etc. It is usually not meant to power the board.
SWDIO/TMS, pin 2: SWD bidirectional data line, or JTAG TMS.
GND, pins 3 and 5: Ground reference and return path.
SWDCLK/TCK, pin 4: SWD clock, or JTAG clock.
SWO/TDO, pin 6: Optional trace/output signal, or JTAG TDO.
NC/TDI, pin 8: Usually unused in SWD mode; used as JTAG TDI in full JTAG mode.
GNDDetect, pin 9: Ground detect / cable detect on some tools.
RESET, pin 10: Optional target reset control.
How it operates in a circuit:
The connector simply routes debugger signals between the external debug probe and the target MCU.
In SWD mode, the essential signals are usually VTref, GND, SWDIO, SWDCLK, and often RESET.
In JTAG mode, more pins are used: TMS, TCK, TDI, TDO, plus reset/reference/ground.
It should be placed near the MCU if possible, with short, clean traces for SWDIO and SWDCLK. Pull-ups/pull-downs are usually determined by the MCU vendor’s reference design.
Common applications:
ARM Cortex-M development boards
Production programming fixtures
Firmware debugging
Factory test access
Low-volume bring-up and diagnostics
Embedded products that need a compact debug connector
Family / series context:
This belongs to the ARM Cortex 10-pin 0.05 in debug connector standard, often called the Cortex Debug connector.
Compared with the older 20-pin 0.1 in ARM JTAG header, this version is much smaller and better suited for compact PCBs.
Compared with 6-pin SWD headers, it supports more optional signals such as SWO, JTAG TDI/TDO, GND detect, and reset.
Compared with Tag-Connect cable pads, it uses a physical mating connector, making repeated debugging easier but consuming more board height and BOM cost.
Variations include shrouded vs unshrouded headers, vertical vs right-angle, through-hole vs SMD, keyed/missing-pin versions, and smaller board-edge or pogo-pin alternatives.
Notable characteristic: this connector is mainly a debug/programming interface, not a user-facing communication port. It normally carries low-current logic-level signals and should match the target MCU’s I/O voltage through VTref.
Wirelessly connects nets on schematic. Used to organize schematics and separate functional blocks. To wirelessly connect net portals, give them same designator. #portal
General Purpose Thick Film Standard Power
and High-Power Chip Resistor
47 kOhms ±5% 0.125W, 1/8W Chip Resistor 0805 (2012 Metric) Automotive AEC-Q200 Thick Film
Features:
- RMCF – standard power ratings
- RMCP – high power ratings
- Nickel barrier terminations standard
- Power derating from 100% at 70ºC to zero at +155ºC
- RoHS compliant, REACH compliant, and halogen free
- AEC-Q200 compliant