The AD7741/AD7742 are a new generation of synchronous voltage-to-frequency converters (VFCs). The AD7741 is a single-channel version in an 8-lead package (SOIC/DIP) and the AD7742 is a multichannel version in a 16-lead package (SOIC/DIP). No user trimming is required to achieve the specified performance.The AD7741 has a single buffered input whereas the AD7742 has four buffered inputs that may be configured as two fully-differential inputs or three pseudo-differential inputs. Both parts include an on-chip +2.5 V bandgap reference that provides the user with the option of using this internal reference or an external reference.The AD7741 has a single-ended voltage input range from 0 V to REFIN. The AD7742 has a differential voltage input range from –VREFto +VREF. Both parts operate from a single +5 V supply consuming typically 6 mA, and also contain a power down feature that reduces the current consumption to less than 35 μA.ApplicationsLow Cost Analog-to-Digital ConversionSignal IsolationAD7742 is obsolete