Smartie
Member
LED Driver Issues [Solved] (Human Error)
Hey guys,
I've been working on a LCD watch project as some of you may know already.
I got the circuit boards from Batch PCB a few days ago and I have assembled one of the boards. this is my very first SMD board and have hand soldered all the components (Solder Paste does a great job![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
However when I program my MCU to turn on the LED Driver, Nothing happens, the charge capacitor does not go over the circuits normal voltage and there is about 1V output on the LEDs...
I'm using a LT3593 LED Driver (Datasheet), it is designed to provide a programmed constant current and boosting the voltage until that current is met (max 20mA though).
I have tested the output of the MCU to make sure the LED Driver is getting the signal, which it is. I have attached the schematic of the LED Driver.
The LEDs are the backlight to a Nokia 6100 LCD screen which require 6V to run but my battery only supplies 3.7V hence why I'm using a LED Driver to boost the voltage.
The inductor i scavanged from another PCB from my junk box, it reads '100' and I'm sure it's 10uH, (I honestly did try Googling it)
Any idea what's wrong?
Cheers
roman
Edit: The LT3593 is the 6pin chip on the bottom, to the left is the inductor, next a Schottky Diode then the two Capacitors C4 and C5
Hey guys,
I've been working on a LCD watch project as some of you may know already.
I got the circuit boards from Batch PCB a few days ago and I have assembled one of the boards. this is my very first SMD board and have hand soldered all the components (Solder Paste does a great job
However when I program my MCU to turn on the LED Driver, Nothing happens, the charge capacitor does not go over the circuits normal voltage and there is about 1V output on the LEDs...
I'm using a LT3593 LED Driver (Datasheet), it is designed to provide a programmed constant current and boosting the voltage until that current is met (max 20mA though).
I have tested the output of the MCU to make sure the LED Driver is getting the signal, which it is. I have attached the schematic of the LED Driver.
The LEDs are the backlight to a Nokia 6100 LCD screen which require 6V to run but my battery only supplies 3.7V hence why I'm using a LED Driver to boost the voltage.
The inductor i scavanged from another PCB from my junk box, it reads '100' and I'm sure it's 10uH, (I honestly did try Googling it)
Any idea what's wrong?
Cheers
roman
Edit: The LT3593 is the 6pin chip on the bottom, to the left is the inductor, next a Schottky Diode then the two Capacitors C4 and C5
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