ROBERTO BERNER

MULTIPLEXED 7 SEGMENT LED DISPLAY DIRECT DRIVE FROM PORT 9S08QE8CLC POSSIBLE ?

Discussion created by ROBERTO BERNER on Mar 7, 2012
Latest reply on Mar 19, 2012 by ROBERTO BERNER

Hello friends, I need to connect 6 multiplexed 7 segment LED display digits to a 9S08QE8CLC MPU. Considering 1 ms per digit on-time ( 1/6 duty cycle common cathode active), is it possible to drive the 7 segments through current limiting resistors for each segment and a MOSFET for switching each cathode to ground ? I thought 27 Ohms limiting resistors for a 60 mA peak current for each segment, considering ~ 1.5 V drop @ 60 mA with 3.00 V power supply, 10 mA regular LEDs. The idea is not to use driver MOSFET's or buffers.

 

Any comments will be very much appreciated.

 

Kind regards

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