SI2457-D-FT Silicon Laboratories Inc, SI2457-D-FT Datasheet - Page 288

• Manufacturer Part Number: SI2457-D-FT
• Description: IC ISOMODEM SYSTEM-SIDE 24TSSOP
• Manufacturer: Silicon Laboratories Inc

Specifications of SI2457-D-FT

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

AN93
Examples of Line Impairments
DTMF Distorted by Low Line Level
Solutions:
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288
Fix the telephone line.
Lower the DTMF level with AT:U46, 0BD0 or AT:U46, 0CF0
Check the loop-current level with AT:R79 and AT:R6C.
Figure 71. Defective DTMF
Figure 72. Normal DTMF
Rev. 1.3