75T202
DESCRIPTION w
The 75T202 and 75T203 are plete Dual-tone Multifrequency (DTMF) receivers detecting a selectable group of 12 or 16 standard digits. No front-end pre-filtering is needed. The only externally required ponents are an inexpensive 3.58 MHz television “colorburs” crystal (for frequency reference) and a bias resistor. Extremely high system density is made possible by using the clock output of a crystal-connected 75T202 or 75T203 receiver to drive the time bases of additional receivers. Both are monolithic integrated circuits fabricated with low-power, plementary symmetry MOS (CMOS) processing. They require only a single low tolerance voltage supply and are packaged in a standard 18-pin plastic DIP. w at .D w h S a t e e
4U m o .c
75T202/203 5V Low-Power DTMF Receiver
February 1998
FEATURES
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- Central office quality NO front-end band-splitting filters required Single, low-tolerance, 5-volt supply Detects either 12 or 16 standard DTMF digits Uses...
