Help...problem with test circuit of SG3524..with duty ratio.

[AbhimanyuSingh1]

This is one of the test circuits given in datasheet of SG3524, with a little modification, mostly insignificant, like changing the value of inductor and using just one BJT instead of 2, as given in datasheet. I am not getting any output there. The expected % volts is not there. The signal out of pin 13 has a duty ratio of almost 0. What could the reason be. What possible mistake have I made. Even if I change the voltage at pin 2 (off course remove this voltage divider and put a rheostat), I dont find any change in duty ratio.
Also once it happened, in another occasion that I was getting 2 volts at that point once I switched on the circuit and that voltage remained there even after i switched off the power supply. What could be a reason for this.
The circuit is built on a bread-board. So its a little lousy, but there were no loose-wires.
I am posting the circuit diagrams. The first file is the circuit i have built and the second file is the test circuit given in datasheet of Texas Instruments.

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[indulis]

These are both buck converters. First, what do you have for a load? You gotta have one, or else it will pulse skip or just shut down once the 500

 

[AbhimanyuSingh1]

Thank you for your reply and for your concern.
There is no load, which I thought would be inappropriate at first. The value of the inductor is 0.150 mH.
Ramp voltage, as in normal situation is there on pin 7. Pin 12 and 13 are shorted and there is signal with almost 0 duty ratio on pin12 and 13 shorted.

 

[indulis]

Put some minimal load on the output... say 20%.

 

[lucy1]

what is load?

 

[indulis]

"Load" as in draw a load current out of the output.