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BLF driver DDm-17 [rev04b][tried & tested]
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BLF driver DDm-17 [rev04b][tried & tested]
by DEL.
2
layer board of
0.69x0.69
inches
(17.42x17.42
mm).
Shared on
January 12th, 2017 23:32.
BLF flashlight driver, 17 mm, DD+m
Features
- 17 mm direct drive + 350 mA regulator LED driver
- No OTC - Intended for e-switch, memory-decay or no-memory firmware.
- R5 to eliminate unintentional Vcc boosting during PWM.
- R3 to eliminate unintentional flashing during mode changes.
- Oversized heat plane for the 7135 with good thermal link to the ground ring.
- Generous 0603 pad sizes through-out that will accept 0805 parts as well.
- ‘SS’ SOIC package size for MCU. Tiny85 requires pin-bending to fit.
Revision changes
- Move MCU and 7135 slightly for better programming clip clearance
Suggested parts list
- U1: Atmel Attiny25, SSU or SSN package
- U2: 7135 350 mA LED driver
- Q1: Vishay SiR800DP
- C1: 10 uF, X5R or better, 0603 or 0805
- D1: Schottky diode, 200 mA 20 V or better, 0805 or SOD323
- R1: 22 / 330 kohm, 1%, 0603 (R1, R2 larger values for e-switch lights)
- R2: 4.7 / 100 kohm, 1%, 0603
- R3: 100 kohm, 5%, 0603
- R5: 4.7 ohm, 5%, 0603