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Ver1.1
8
BL8506
Function description:
Comparator
High precision low temperature co-efficiency reference voltage is applied to the
negative input of a comparator. Input voltage, divided by resistor array of Ra Rb and Rc,
is applied to the positive input of the comparator. Output of the comparator controls a
pair of NMOS and PMOS switches, generating the hysteresis. Output of the comparator
passes a series of buffer to drive the output CMOS pair.
+ VDET,- VDET,VHYS can be calculated as follows:
- VDET =VREF*(1+Ra/(Rb+Rc))
+ VDET =VREF*(1+(Ra+Rd)/Rb)= VREF *(1+(Ra+Rc)/Rb)
VHYS=+ VDET -(- VDET)= VREF*(Ra+Rb+Rc)(1/Rb-1/(Rb+Rc))