L293D Motor Runs at low Voltage

[yovenim]

Hi all,

I need a small help regarding L293D.

I am making a small project using L293D. Bo motor which hardly consumes 60ma at 5v.
i am powering my L293D using a step up circuit 3.7V to 5V from 3.7v li-ion battery.

output current from step up circuit is 200ma which is not a issue.
my problem is the motor voltage pin no 8 shows me 5.12v. when i drive my motor the voltage accross shows me only 3.00v... due to which the motor drives very slow.

can anybody please help why this happen....

 

[crutschow]

The output drivers for the L293 are Darlington stages which have a significant voltage drop (below):
To get near to 5V output, you need to a device that uses MOSFETs, such as the TB6612FNG.

 

[tepalia02]

The step-up converter is stepping up the voltage. But the current is being lower. L293D is not getting enough input current. Try to power it up with batteries directly.