Post by thread:[OT] 0-10V 100mA supply

As the description says....0-10V @100mA, input is 24VDC So the way I see choices are: Micro with PWM output driving an opamp (+24VDC rails...cable driver maybe?) DAC driving a opamp again Adjustable LDO - using a digital pot to adjust the ouput (micro drives over I2C) So what might the forum choose?

On 17/4/2012 12:08 AM, alan smith wrote: > As the description says....0-10V @100mA, input is 24VDC > > So the way I see choices are: > Micro with PWM output driving an opamp (+24VDC rails...cable driver maybe?) > DAC driving a opamp again > Adjustable LDO - using a digital pot to adjust the ouput (micro drives over I2C) At 0.1 V / 100 mA you are dissipating 2.4W. Not your yellybean OpAmp! Buck converter? -- Wouter van Ooijen -- ------------------------------------------- Van Ooijen Technische Informatica: http://www.voti.nl consultancy, development, PICmicro products docent Hogeschool van Utrecht: http://www.voti.nl/hvu C++ on uC blog: http://www.voti.nl/erblog

> As the description says....0-10V @100mA, input is 24VDC > > So the way I see choices are: > > Micro with PWM output driving an opamp (+24VDC rails...cable driver maybe?) > > DAC driving a opamp again > > Adjustable LDO - using a digital pot to adjust the ouput (micro drives over I2C) > > > So what might the forum choose? At that input voltage I would research buck regulators designed for PoE or automotive use ... -- Scanned by iCritical.

At 06:08 PM 4/16/2012, you wrote: >As the description says....0-10V @100mA, input is 24VDC > >So the way I see choices are: > >Micro with PWM output driving an opamp (+24VDC rails...cable driver maybe?) > >DAC driving a opamp again > >Adjustable LDO - using a digital pot to adjust the ouput (micro >drives over I2C) > > >So what might the forum choose? Easier if you can relax the spec to something more like 1.5-10V, otherwise having a negative supply might be better. Digital pot (or DAC) and regulator is easy.. you don't need an LDO since you have plenty of input voltage. If you knock the 24V down to 12V first with a buck regulator then use a linear (eg. LM317) that would not be a bad solution. Only a small heat sink required on the LM317 (1.2W), and relatively low noise. You get the short-circuit and thermal overload protection included. Best regards, Spehro Pefhany --"it's the network..." "The Journey is the reward" spam_OUTspeffTakeThisOuTinterlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com