Click to expand full text
DESCRIPTION
w
The 75T202 and 75T203 are complete 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 components 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, complementary 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 .
75T202 Datasheet
