I would like to drive 4" large 7-segments LEDs from an Arduino/ESP8266(WiFi Module) @ 3.3V.
7-segment LED is a Common Anode type - 9V @ 20mA per segment (~150mA).
I have understood that I need to use a some LED driver with more than 150-mA Current Limit Capability and TPIC6C595 seems to the best option.
But, But operating voltage of TIPC6C595 is 4.5-5.5V.
Please suggest, Some alternative "Driver Ic" which can work as 3,3V. Some Ic similar to TIPC6C595(Its a Shift Register).
But I wanted to create a PCB specific for this project. So, It seems to be that I have to use three different voltage regulators (3.3V, 5V, 9V) for Wifi, LED Driver and 7Segments respectively.
If there is any alternative IC, which can drive 7-Segement LEDs @ 3.3V as Vcc would be very helpful.
BhanuTejaJ:
If there is any alternative IC, which can drive 7-Segement LEDs @ 3.3V as Vcc would be very helpful.
The vast majority of the projects I've done have been with a 3.3V microcontroller. I almost always use a 5V regulator with these projects in order to use support chips which require 5V supplies.
Do you plan to use a TPIC6C595 with each display or do you plan on controlling the anodes of each display? If you will control the anodes, do you have an IC in mind to do this?
One option would be to connect the anode of each display to the 9V supply and use a shift register chip for each digit.
You'll want a current limiting resistor between the display's cathode and the TPIC6C595 chip.
74HC595 shift registers can be powered with 3.3V but I doubt they're a good match for this project.
There may be other 3.3V chips which would do what you want, but I'm not aware of them.
Do you plan to use a TPIC6C595 with each display or do you plan on controlling the anodes of each display? If you will control the anodes, do you have an IC in mind to do this?
Yes, I am thinking of using TPIC6C595 with each display and connect anodes directly to 9v( I have common Anode 7Segment 4" LED's)
74HC595 shift registers can be powered with 3.3V but I doubt they're a good match for this project.
Yes, Thanks again. I also checked the datasheet. 54/74HC595 both IC can work at 3.3V, but their max current limit is only 70mA. Here we need >150mA.
Post the link to the display.
The large Kingbright displays I have worked with have four ~2.2volt LEDs in series per segment.
A forward voltage of ~8.8volt.
If the datasheet states a forward voltage of 9volt, that does NOT mean you can use a 9volt supply.
You need some extra voltage for the current limiting resistor or constant current driver.
I run my displays on 12volt.
Leo..
Finally, Now thinking of using, 74Hc595 with ULN2803 to drive Seg A-G & Dp (with equivalent current limiting resistor). and Three transistors for supplying 9v to Anodes for using multiplexing concept( as I have only 3 - 7Segment displays in my project).
Need help with transistors arrangement...PNP...MostFet.. DontKnow!, Which transistor should I use to drive 7 Segments at 9V and ~150mA current (8 Segments*20ma) and which faster switching rate for multiplexing.
Any specific example or transistor name where can I refer to?
DontKnow!, Which transistor should I use to drive 7 Segments at 9V and ~150mA current (8 Segments*20ma) and which faster switching rate for multiplexing.