LEDs for photographic applications

Saturday, November 29, 2003

Stroboscope Specs

// posted by Richard @ 6:54 PM

Comprehensive document on MOSFETs. Shows basic open collector TTL drive circuit on page 25.

// posted by Richard @ 6:39 PM

Switch regulator specifically designed for powering LEDs from line voltage.

// posted by Richard @ 6:11 PM

Thursday, November 20, 2003

Charge Pump Doubles Negative�Voltage

// posted by Richard @ 7:18 PM

Describes cap only voltage inverter part MAX1681, that can synthesize a negative voltage of -10 volts with 5.5 volts in.

Also see negative doubler app note.

// posted by Richard @ 7:17 PM

Tuesday, November 18, 2003

SPICE models... Source of SPICE models is at

http://homepages.which.net/~paul.hills/Circuits/Spice/ModelIndex.html

// posted by Richard @ 1:45 PM

Sunday, November 16, 2003

This is a light to voltage converter with integral Blue or Green filter.
Should work for auto brightness regulation.

// posted by Richard @ 8:51 PM

JFET - linearized variable resistor

Shows how to use a JFET as a variable resistor in a circuit with a control voltage to vary the resistance. This circuit is probably adaptable to the Infineon TLE 4241.

// posted by Richard @ 8:13 PM

Neat chip for constant current supply. Has variable current and adequate voltage. Also has enable input that could be used for either PWN or true enable.

Current set makes inclusion of a feedback brightness circuit pretty simple.

// posted by Richard @ 7:44 PM

Saturday, November 15, 2003

Motorola data sheet has a "lab" supply schematic in figure 20. It could be useful... It could also be adapted.

// posted by Richard @ 5:49 PM

Friday, November 14, 2003

Constant current switching supply. Two op amps. cool.

// posted by Richard @ 1:46 PM

EDN Access-- 6.22.95 40V current source operates from -40 to 85°C

Good constant current supply based on LM317. Good notes.
Also saved in photo file on disk drive.

// posted by Richard @ 1:31 PM