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www.DataSheet4U.com Freescale Semiconductor
Technical Data
MC14578 Rev 2, 05/2005
CMOS Micro-Power Comparator plus Voltage Follower
The MC14578 is an analog building block consisting of a very-high input impedance comparator. The voltage follower allows monitoring the noninverting input of the comparator without loading. Four enhancement-mode MOSFETs are also included on chip. These FETs can be externally configured as open-drain or totem-pole outputs. The drains have on-chip static-protecting diodes. Therefore, the output voltage must be maintained between VSS and VDD. The chip requires one external component. A 3.9 MΩ ±10% resistor must be connected from the Rbias pin to VDD. This circuit is designed to operate in smoke detector systems that comply with UL217 and UL268 specifications.