Hey, I'm designing a voltage to current converter using a single 5v supply. Most bipolar op amps (that aren't open collector) don't seem to go that low. I need to ensure that the input and output are both rail to rail so that leaves me with generally just cmos op amps.
After simulating my circuit within LTspice, the LT1006 and LT1007 fit the bill perfectly but seem a bit overspecced and pricey for the job.
How would the CA3240 hold up? I know its a tad old but it still boasts quite good spec. Failing that, the TS272 or LMC662?
The input will be a time varying signal but will have a maximum period of 50Hz so bandwidth is not a major biggy. The output will be a green LED with a 120ohm feedback resistor The green LED has a forward voltage of 2.8v (measured @ 20mA) therefore at 5v, maximum current flow with the 120ohm feedback resistor can be about 18mA. The input voltage will be about 1v so theoretically with 1v dropped across 120ohm, the current flow will be about 8mA which is fine.
Would the TS272 be suited to this application? (Its the cheapest of the bunch, swiftly followed by the CA3240)
Cheers
After simulating my circuit within LTspice, the LT1006 and LT1007 fit the bill perfectly but seem a bit overspecced and pricey for the job.
How would the CA3240 hold up? I know its a tad old but it still boasts quite good spec. Failing that, the TS272 or LMC662?
The input will be a time varying signal but will have a maximum period of 50Hz so bandwidth is not a major biggy. The output will be a green LED with a 120ohm feedback resistor The green LED has a forward voltage of 2.8v (measured @ 20mA) therefore at 5v, maximum current flow with the 120ohm feedback resistor can be about 18mA. The input voltage will be about 1v so theoretically with 1v dropped across 120ohm, the current flow will be about 8mA which is fine.
Would the TS272 be suited to this application? (Its the cheapest of the bunch, swiftly followed by the CA3240)
Cheers