75T2090

DESCRIPTION TDK Semiconductor’s 75T2089/2090/2091 are complete Dual-Tone Multifrequency (DTMF) Transceivers that can both generate and detect all 16 DTMF tone-pairs. These ICs integrate the performance-proven 75T202 DTMF receiver with a DTMF generator circuit. The DTMF receiver electrical characteristics are identical to the standard 75T202 device characteristics. The DTMF generator provides performance similar to the Mostek MK5380, but with an improved (tighter) output amplitude range specification and with the addition of independent latch and reset controls. An additional feature of the 75T2090/2091 is "imprecise" call progress detector. The detector detects the presence of signals in the 305-640 Hz band. (continued) 75T2089/2090/2091 DTMF Transceivers FEATURES April 2000 DTMF Generator and Receiver on one-chip Call progress detection (2090/2091 only) Early detect output (2091 only) DTMF Receiver exhibits excellent speech immunity Analog input range ...