Strange Behavior on DC/DC Converter

[tyguy2]

Hello,

I've been tinkering with the PAM2401SCADJ (https://www.diodes.com/assets/Datasheets/PAM2401.pdf). I'm using it in an application that runs off a single AAA battery, and boosting that to 3.6 volts. Looking over the datasheet, this chip should easily supply 100 ma (see page 3, first graph.) However, I can't load it down with more than 35 ma; after that the voltage drops significantly. I'm not sure if I'm reading the datasheet wrong or have just wired it incorrectly. I have the MSOP-8 package, so no PG pin for current limiting. Currently, when I try to power a small motor, it will turn on and off quickly, and the oscilloscope confirms the device is sending short pulses to it. On smaller loads, it sends continuous voltage. Am I tripping some sort of over current protection?

[tyguy2]

Update:
I connected the RSET to Voltage in, and now it seems to be supplying more current, and it occasionally does supply full current, but it still fails to consistently reach its full output and voltage. 

[ahbushnell]

A motor will pull more current when it ramps up to speed.  Could that be the problem?

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[tyguy2]

A motor will pull more current when it ramps up to speed.  Could that be the problem?

I wouldn't think so. The motor intermittently reaches full speed, but if the initial current draw was the issue, once it sped up, it would maintain its speed. 

Edit: Just to confirm, I spun the motor by hand while powering it, no go

[tyguy2]

Figured out the issue, I had to reduce the inductance of the coil from 2.2 uH to 1.5 uH

[thexeno]

Hi, personal curiosity: what part exactly did you used? It should normally work with higher inductor, not viceversa.