L6271

Each L6271 has two output stagesscaled in cur- rentbya factorK =10.

In voltagemodeconfigurationthetwo outputsare shorted.

In charge mode configuration OUT1 drives a ca- pacitor Cint and is closed in feedback, while OUTK drives thepiezo, mirroring thecurrent sup- plied to Cint, with a current multiplied by a K fac- or(seeFig.1).

Thesupplyvoltagecanbeinternallygeneratedby theDC-DCconverter,or external,maintainingthe DC-DC converter in sleep mode (PIN15 shorted to ground),in thiscase the supply voltage can be 0 to V512+4 minimum value up to 80V in single supplyor V512+4to 40Vsymmetricalto ground.

The L6271s have 130dB DC gain and the Band- width is 500KHz. Stability is granted with a mini- mum gain of 20dB, for a capacitive load in the range0.4nFupto 24nF.

The L6271s can besuppliedwith HVP-HVM (dou- ble supply mode) or with HVP-Ground (single supply mode). In both cases they can achieve a rail-to rail outputdynamic range with a maximum load currentof ±75mA.

In double supply mode the input stage has - 5V/+5V dynamic range, while in single supply modeit has1.2Vup to 10Vinput dynamicrange. A 2.5V internal reference voltage is available at one pin (Vref) thatcan be usedto closethe feed- back if the input signal is symmetrical around 2.5V.

In this case the output dynamic is symmetrical around 2.5V. L6271 is present a 2.5V down level shifter that can be connectedbetween the input signal and the input of the opamp, to work inter- nally witha signalsymmetricalto ground.