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Printed Circuit Boards from ALLPCB

admin — Wed, 03 Jan 2018 12:16:06 +0000

For my development projects I recently ordered 10 pieces of 100x100mm double layer PCBs from ALLPCB and the process went great through and got 13 pieces as a bonus for only $5(!) including the express DHL delivery.

Order details: 10 pcs of 100x100mm PCBs for TSSOP, QFN, DSBGA with 0.5mm pitch 0.2mm pads, 8 – 32mil tracks, vias 0.4mm/40mil drill
Drilling accuracy: +-0.05mm as expected, 0.3mm holes, perfect for this precision class
Copper etch accuracy: perfect, sharp edges and peaks, follows 6mil details
Soldermask: no overflow, resolution superb, goes exactly even between 0.5mm spaced pads, no problem with arbitrary polygons, see the attached images
HASL finish: conform, no uncovered areas
Silkscreen: perfect, 0.1mm line, 0.8mm height text clear
Electrical test: full
Time of fabrication: 27 hours from first step (cutting) to packing
Time from placing an order to delivery doors: 7 days, delays: 2 days to clear the soldermask requirements, 2 days on local holidays DHL delivery
Factory support: fast by email, clear and constructive, thanks to Della Deng

Only one restriction was unexpected: text on the bottom soldermask layer was refused by factory, they offer text only on silkscreen, this information is not published, arbitrary soldermask polygons are allowed.

OVERALL RATING: GREAT, fast and accurate process and express delivery by DHL, unbeatable value/price ratio, recommending ALLPCB for fast turn prototype boards.

Definitely will order again next time.

ARM Cortex-M4 core MCUs

admin — Mon, 02 Jan 2012 21:23:27 +0000

Many embedded applications today can use 32bit microcontrollers based on ARM Cortex core which is beating down the 8bits prices and support. When you need more computing power including DSP instructions built in RISC, a huge amount of peripherals, timers, interfaces, high-pin count in FQP and BGA packages, up to 1MB of Flash and >128k RAM memories,… in one package, then you may look on a CortexM4 portfolio offered by Freescale, ST, TI, NXP.

Freescale offers its Kinetis K10 – K60 series with TOWER System development boards support. ST comes with STM32F4xx, NXP with LPC4xxx, TI with LM4Fxxx. Production samples are available from all mentioned vendors.

Foil conductor – fail and fix – all 6-sigma certified

admin — Sun, 30 Oct 2011 21:18:57 +0000

One friend called and asked me for help. His Honeywell Thermostat (model …) failed to display data on its LCD.

to be continued

LPCxpresso in my mailbox !

admin — Sun, 11 Sep 2011 21:20:07 +0000

Today landed!

Credits go to NXP and EBV for their special offer of free LPCXpresso demo/evaluation boards equipped with the target LPC1114 CortexM0 MCU. As NXP stated:

“With over 45 DMIPS of performance compared to the sub-DMIP performance typical of 8-bit MCUs and to 3-5 DMIPS for 16-bit MCUs, NXP’s LPC1100L can not only execute basic control tasks but also sophisticated algorithms, making even the most complex tasks within reach. Shorter time to do more tasks translates directly into lower energy consumption. This level of performance is delivered at 50 MHz, with extensive power optimization, at less than 10 mA.

Based on the ARM Cortex-M0 processor, the LPC1100L microcontroller delivers the industry’s lowest 32-bit active power consumption at 130 μA/MHz and reduces deep sleep current by a dramatic 60 percent.”

The power consumption parameter 130 μA/MHz in fact correlates with other CMOS process architectures implemented today.

For developers is most important the volume of product errata, quality of documentation and development boards/samples support. The LPCXpresso demo board has an hardware debugger based on secured LPC3xxx ARM9 core and the communication protocol is closed proprietary, so the user is limited to use a software debugger suite by CodeRed only. It’s serious limitation but for such a demo board is acceptable.