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popn_pico/PCB/agg-kicad/agg.pretty/README.md
2022-08-22 21:51:48 +08:00

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# PCB Footprints
## Common Guidelines
* Origin/anchor on part centre
* Pad 1 on the left and then at the top
* Ensure rotational symmetry for symmetric parts
* Text has size 1mm x 1mm and thickness 0.15mm (checked automatically)
* Aim to conform to IPC-7351B footprint design
* Reference and Value fields:
* On the `F.Fab` layer (checked automatically)
* May only be hidden for non-functional parts such as mounting holes
* Place just outside the part courtyard, without overlapping the part
* If the part is usually arrayed vertically, place on left and right, with
text running vertically
* If the part is usually arrayed horizontally, place on top and bottom,
with text horizontal
* Otherwise, prefer top and bottom
* Reference on top or left, value on bottom or right
* Fabrication Layer:
* Include reasonably accurate part drawing
* Courtyard:
* Lines 0.01mm thick on 0.05mm grid (checked automatically)
* Clearance:
* 0.25mm normally
* Other clearances as applicable per-package
* Silkscreen:
* May be omitted only for very small footprints where inclusion would
impede close packing or soldering, or for non-functional parts such as
mounting holes
* All lines 0.15mm thick (checked automatically)
* Provide pin 1 indicator where applicable
* No silk over exposed copper
* Internal drawings where possible
* Not for ICs with exposed pads
* Be careful of situations where the height of the silk could cause
soldering issues
* Placement alignment indications for no-lead packages will need to be
external
* In general prefer less silk visible post-assembly
## Associated Documentation
* Has the footprint been validated in practice? With what symbol? Where?
* Link to any specific layout recommendations or requirements
* Any other notes / gotchas
Footprints in `unchecked/` have not been standardised or documented yet.
## Footprints
### 0201, 0201-L, 0402, 0402-L, 0603, 0603-L, 0805, 1206
Imperial sized chip device.
* Footprints are IPC-7351B compliant
* Default NOMINAL environment, `-L` parts in LEAST environment
* Clearance and courtyards are all 0.25mm from the pad edges
* Fabrication layer shows typical device and terminal size
* Generally all tested in production but are by no means process-optimised
### 0603-LED
0603 (aka 1.6mm x 0.8mm) sized LED.
* Standard 0603 footprint pads
* LED polarity arrow with pin 1 as cathode
* Farnell codes:
* Red 2290329
* Green 2290328
* Amber 2290330 ("yellow")
* Blue 1686062
### 0805-LED
0805 (aka 2.0mm x 1.25mm) sized LED.
* Standard 0805 footprint pads
* LED polarity arrow with pin 1 as cathode
* Farnell codes:
* Red 5790840
* Green 5790852
* Yellow 5790876
* Orange 5790864
* Blue 8554749
### SOIC, MSOP, LQFP, QFN, DFN, LGA, LPCC, others
Standard footprints, either from IPC-7351B in nominal environments or otherwise
modified for a specific package or device.
Generated automatically by `scripts/icmod.py`. Please see the notes by each
footprint in that script for further details.
### MICROUSB_MOLEX_47589-0001
MicroUSB connector.
* Farnell 1568023
* Not tested yet
* Bottom mount (so USB cables will be upside down if footprint is on top)
* Footprint uses round drill hits for oblong slots
* Probably wants hand soldering the through connections
### MICROSD_MOLEX_503398-1892
MicroSD card holder.
* Farnell 2358234
* Used successfully
### M3_HOLE, M3_MOUNT
M3 sized mounting holes.
* The `M3_MOUNT` variant includes a no-mask region with extra drill hits for a
locking washer.
* The `M3_HOLE` courtyard does _not_ include space for a bolt head or washer
(as it may not always be required) so be sure to check this or use the
`M3_MOUNT` variant.
### WIREPAD
3mm diameter circular copper pad. Useful for particularly large testpoints and
pads for soldering wires to.
### PowerFLAT5x6
Dual switching N-MOSFET (not linked), 9mΩ Rdson.
* STL15DN4F5
* http://www.st.com/web/en/resource/technical/document/datasheet/CD00279555.pdf
### PowerPair3x3
Dual switching N-MOSFET totem pole, 14mΩ (upper) and 7mΩ (lower) Rdson.
* SiZ340DT
* http://www.vishay.com/docs/62877/siz340dt.pdf
### PowerPAK SC-75-6L-Single
Single switching N/P MOSFET.
* SiB452DK, SiB433EDK
* http://www.vishay.com/docs/68832/sib452dk.pdf
* http://www.vishay.com/docs/65652/sib433ed.pdf
### PowerPAK-SO-8
Single switching P-MOSFET, 3mΩ Rdson.
* Si7157DP
* http://www.vishay.com/docs/62860/si7157dp.pdf
### SON2x2
Single switching P-MOSFET, 59mΩ Rdson.
* CSD25310Q2
* http://www.ti.com/lit/ds/symlink/csd25310q2.pdf
### VML1006
Single switching N MOSFET.
* RV2C010UN
* http://rohmfs.rohm.com/en/products/databook/datasheet/discrete/transistor/mosfet/rv2c010unt2l-e.pdf
### VLS201610HBX-1
VLS201610HBX-1 Inductor series.
* https://product.tdk.com/info/en/catalog/datasheets/inductor_commercial_power_vls201610hbx-1_en.pdf