Low Noise Photodiode Transimpedance Circuit

2 layer board of 0.99x1.36 inches (25.04x34.62 mm).
Shared on April 28th, 2015 04:20.

Designed for OPA827 and OPA 4227, this circuit amplifies a very small photodiode current input to a +-15V voltage output. OPA827 is chosen to minimize bias current, offset voltage, noise density and price!

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BLF SRK FET V2 - 46mm

2 layer board of 1.89x1.83 inches (48.01x46.43 mm).
Shared on April 28th, 2015 01:37.

This is an update on the original BLF SRK FET driver which was designed by Mattaus, and inspired by the work of Comfychair and several other BLF members.

REQUIRED Parts List (1S Input):

• FET: D2PAK
• RGATE: 0805 - 10 ohm - 50 ohm
• R1: 19.1K (1S input)
• R2: 4.7K
• U1: attiny13a-SSU
• C1: 0805 - 10uF - X5R (or better)
• D1: SOD-323 Schottky Diode

REQUIRED Parts List (2S+ Input):

• FET: D2PAK
• RGATE: 0805 - 10 ohm - 50 ohm
• R1: 36K (2S-3S input)
• R2: 4.7K
• U1: attiny13a-SSU
• C1: 0805 - 10uF - X5R (or better)
• CLDO: 0805 - 10uF - X5R (or better)
• LDO: Many fit - choose on price and availability

OPTIONAL Parts:

• 7135: Optional 7135 for secondary PWM output (Pin 5)
• OTC (for clicky FW use): 0805 - 1uF - X7R
• Ctemp: 0805 Capacitor
• RT1; RT2; T-; T+: Connection points and related component pads for external temperature sensor

Changes from original:

• Additional vias
• Deleted L1 and D1 pads (they were mostly unused)
• Added more LED pads
• Added optional 7135 on secondary PWM channel
• Added optional LDO for 2S+ use
• Changed ADC LVP feed point; now connected directly to input
• No more jumpers or solder bridges needed for switch pads
• SW- and several other low current pads now have thermal relief for easier soldering
• Added optional OTC pad for clicky use
• Added external temperature sensor provisions
• Added gate resistor / pulldown resistor for big FET

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MotionSensorTest Board.v01

2 layer board of 0.71x0.51 inches (17.91x12.83 mm).
Shared on April 28th, 2015 00:03.

Breakout board for four popular motion sensors including the Invensense MPU9250, ST’s LSM9DS0, Maxim Integrated’s MAX21100, and Bosch’s BMX055. Intent is to characterize the performance of the accelerometers, gyros, and magnetometers on these sensors under the same conditions. Separate analog and digital voltage sources to probe effect of digital signal line voltage and noise on data jitter. At least one interrupt broken out per sensor to allow comparison between polling and hardware interrupt on performance. Is there a significant difference between these sensor elements in terms of jitter, drift, stability, and response time? Let’s find out…

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8-SOIC & 8-MSOP Breakout Board v2

2 layer board of 0.41x0.41 inches (10.34x10.44 mm).
Shared on April 27th, 2015 23:54.

Cost: $0.80 for three.

Breakout board for 8-SOIC and 8-MSOP packages. Converts these 8-pin SMD components to breadboard-friendly 0.1-inch pitch by 0.3-inch width through-hole format. Pins numbered on both sides for quick reference.

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RPi2 I/O Breakout (Single Side)

2 layer board of 1.61x2.17 inches (40.97x55.25 mm).
Shared on April 27th, 2015 23:20.

Break out PCB for Raspberry Pi 2, broken out to the right of the header.

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