I've used Cout = Cadj = 10 uF and Cout = Cadj = 22 uF. I didn't notice a difference between the two in actual use. I just happened to have either 10 uF or 22 uF elsewhere in the design, so I bought in bulk rather than buying two different values.
Tom
Tom
Found these two links and thought I'd share.
LM317 Resistor Calculator
LM337 Resistor Calculator
Regards,
Dan
LM317 Resistor Calculator
LM337 Resistor Calculator
Regards,
Dan
I just wired up an LM337T for regulating -15 V. Input voltage is -20 V. The adjust resistor is 240 ohms, the R1 is 2.7k. I have 100 uF at the output and 33 uF at the adjust. The issue is it does not regulate, the output voltage is more than 18 V. This is at unloaded condition, do I reduce the adjust resistor, or just add some load? How much mA?
Fake LM337? What a world. Again a reason to use parts obtained from official distributors and not the Ebay/Aliexpress lottery.
For positive voltages TPS7A4700 has an equal or lower part count and no extra circuitry needed either (who still has oversight in that jungle?). Excellent regulator with comparable properties as 36V (maximum 20V output though), 1A but then 4 µV of noise. No worries about cap ESR. Just works.
For positive voltages TPS7A4700 has an equal or lower part count and no extra circuitry needed either (who still has oversight in that jungle?). Excellent regulator with comparable properties as 36V (maximum 20V output though), 1A but then 4 µV of noise. No worries about cap ESR. Just works.
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Unfortunately, I myself have come across fake LM337s recently (source: kontel.hu) 3pcs ONsemi fake, "f" (Fairchild?) Is original/works
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You did remember that the pinouts are different to the +ve regulators?
Which of us was the question intended for? 🙂
For my part, I tried it in an already workin pcb, it was so unbelievable to be fake all 3 of them, and later I found 5 more from the same series.
