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TPS61200 diy driver help
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Hiemal
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...So basically you're asking someone to design a layout and driver for you?
No one is going to spend time making anything for that IC, mainly because it can't support that much output current at all. 600 mA from a single li-ion cell kind of sucks.
Asides that the IC is specifically for boosting only. Do a little research next time and maybe look at the datasheet for a minute or two and you would've seen that.
It is cool, though that it works down to 0.4 volts.
No one is going to spend time making anything for that IC, mainly because it can't support that much output current at all. 600 mA from a single li-ion cell kind of sucks.
Asides that the IC is specifically for boosting only. Do a little research next time and maybe look at the datasheet for a minute or two and you would've seen that.
It is cool, though that it works down to 0.4 volts.
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I was asking if the layout on the pdf could be used as a buck/boost driver, or, if wiring it another way would make it boost or buck only.
Also, I can't understand if that layout on the pdf is a high-side driver.
TPS61200 is not boost only, - The TPS61200 integrated circuit (IC) is a low-input voltage synchronous boost converter with down-conversion mode when VIN > VOUT.
600mA in boost mode is more than enough for an LPC-826.
Also, I can't understand if that layout on the pdf is a high-side driver.
TPS61200 is not boost only, - The TPS61200 integrated circuit (IC) is a low-input voltage synchronous boost converter with down-conversion mode when VIN > VOUT.
600mA in boost mode is more than enough for an LPC-826.
Hiemal
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Reading the PDF, it seems that it is a boost converter with a linear sort of mode when the voltage is over the input... AKA, why not just use a linear/buck driver in the first place?
The layout on the PDF file is not high side. The resistor comes after the load (the LED) so it's low side.
The layout on the PDF file is not high side. The resistor comes after the load (the LED) so it's low side.
benmwv
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Don't dismiss it so easy quack!
I made a driver with that chip a long time ago and it's great. Mine is super tiny at 9mm by 9mm and it's great for AA or AAA hosts. It can run off a single Li-ion or a single alkaline! Perfect for blu-ray, single mode 445, low power m140, and even 635 from AA, AAA, 14500, or 10440.
I made a driver with that chip a long time ago and it's great. Mine is super tiny at 9mm by 9mm and it's great for AA or AAA hosts. It can run off a single Li-ion or a single alkaline! Perfect for blu-ray, single mode 445, low power m140, and even 635 from AA, AAA, 14500, or 10440.
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wall: Maybe. Why don't you go search for some? I personally like current sinks rather than sources (such as this). I use a MOSFET instead a BJT for one of the transistors, but you can build them for either. Which MOSFET did I use? Whatever power MOSFET was cheapest in bulk on Mouser.com at the time.
The thing with those current sink/source designs is that you need to get a sense resistor that matches your target current. Sometimes that means finding some exotic or expensive resistor, or putting resistors in weird parallel arrangements. Even if you find the right sense resistor, I tend to see those transistor current sinks/sources as better if you want to control the output--analog or PWM.
If you just want a driver with a low drop-out maybe look into those linear drivers with a dedicated LDO linear regulator or a buck/boost circuit for efficiency.
The thing with those current sink/source designs is that you need to get a sense resistor that matches your target current. Sometimes that means finding some exotic or expensive resistor, or putting resistors in weird parallel arrangements. Even if you find the right sense resistor, I tend to see those transistor current sinks/sources as better if you want to control the output--analog or PWM.
If you just want a driver with a low drop-out maybe look into those linear drivers with a dedicated LDO linear regulator or a buck/boost circuit for efficiency.