Block detection
About the Block detection PCB
Block detection is an open source PCB design by bazauto, published on GitHub under the CERN-OHL-P-2.0 license. It is a 2-layer board measuring 48 × 38 mm, with 28 components from 18 distinct parts.
Other key parts include the TLV9002IDGKR and TLV3212IDGKR. By type, the board carries 11 resistors, 5 capacitors, 4 diodes, 3 connectors, 2 ICs and 1 jumper.
From the project
Two-channel active-high DCC block detector board (KiCad) for the Westgate Hollow layout
CT-based occupancy detection for the Westgate Hollow layout. Two independent channels, each turning the current in an external current transformer into a push-pull logic level: HIGH (3.3 V) = block occupied, LOW (0 V) = clear.
Single +3.3 V rail, fed in through the output header. Board is 48 × 38 mm, 2 layers, four M2 mounting holes.
So that a broken cable or connection under the layout doesn't register as a clear block.
Main components on the Block detection
Block detection bill of materials (BOM)
28 components, 18 distinct parts — part numbers from the project's BOM.
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 1 | TLV9002IDGKR | MSOP-8_3x3mm_P0.65mm | U1 |
| 1 | TLV3212IDGKR | MSOP-8_3x3mm_P0.65mm | U2 |
| 1 | CT1 | TerminalBlock_Phoenix_PT-1,5-2-3.5-H_1x02_P3.50mm_Horizontal | J1 |
| 1 | CT2 | TerminalBlock_Phoenix_PT-1,5-2-3.5-H_1x02_P3.50mm_Horizontal | J2 |
| 1 | OUT | PinHeader_1x04_P2.54mm_Vertical | J3 |
| 1 | MODE | PinHeader_1x02_P2.54mm_Vertical | JP1 |
| 2 | 10k | Potentiometer_Bourns_3269W_Vertical | RV1, RV2 |
| 2 | BAT54S | SOT-23 | D1, D2 |
| 2 | 1N4148W | D_SOD-123 | D3, D4 |
| 2 | 100nF | C_0805_2012Metric | C1, C2 |
| 3 | 10uF | C_0805_2012Metric | C3, C4, C5 |
| 1 | 1.1k | R_1206_3216Metric | R1 |
| 1 | 110R | R_1206_3216Metric | R2 |
| 1 | 100R | R_1206_3216Metric | R3 |
| 2 | 1k | R_0805_2012Metric | R4, R5 |
| 2 | 100R | R_0805_2012Metric | R6, R7 |
| 2 | 100k | R_0805_2012Metric | R8, R9 |
| 2 | 10M | R_0805_2012Metric | R10, R11 |
Block detection design files
The KiCad project lives in the bazauto/block-detection repository on GitHub; these links point at the commit this page was built from.
Block detection: common questions
How big is the Block detection PCB?
The Block detection measures 48 × 38 mm, has 2 copper layers and is 1.6 mm thick.
How many components are on the Block detection?
28 components, from 18 distinct parts, with part numbers taken from the project's own BOM. The full bill of materials is listed on this page.
Where can I download the Block detection design files?
From the bazauto/block-detection repository on GitHub, which has the KiCad layout, the schematic and the BOM; the links under Design files point to each one.
Can I use the Block detection design in my own project?
Yes, under the terms of its CERN-OHL-P-2.0 license, which bazauto chose for the repository.