JB-1 JTAG Bias Board for FIT Base Boards

A small, practical JTAG bias module for FIT (Fault Injection Toolbox) base boards. The JB-1 provides stable pullups for JTAG/SWD lines with a decoupling capacitor up front to smooth transients, making it easy to add or remove JTAG biasing from your test setup.

Provides:

• Pullup/Pulldown resistors for JTAG lines

• One decoupling capacitor placed before the resistors.

Key Features:

• Simple pullup array: Standard pullups for JTAG/SWD signals to ensure defined idle levels.

• Input capacitor: Small capacitor before the pullups to help stabilize surges and reduce noise during switching or injection events.

• Plug-and-play: Fits into the FIT JTAG pullups header for easy insertion and removal.

• Optional use: Leave unpopulated when your debugger supplies biasing or when pullups are not needed.

Why You Need It:

JTAG lines often require defined biasing for reliable operation and repeatable tests. The JB-1 supplies a straightforward, stable bias network you can add or remove without reworking the target or debugger. The input capacitor reduces transient effects when faults are injected or when the target toggles, improving consistency.

Typical Uses:

• Provide pullups for JTAG/SWD when your debugger lacks them

• Stabilize JTAG lines during fault injection or power disturbances

• Quickly enable/disable JTAG biasing in different test configurations

Specifications:

• Components: Array of resistors; single decoupling capacitor

• Interface: Fits FIT JTAG pullups header

• Form factor: Small plug-in module for quick changes