NTAK091.5 Mb DTI/PRI card Page451 of 544
Option11C and 11C Mini TechnicalReference Guide
Digital pad
The digital pad is an EPROM whose address-input to data-output transfer
function meets the characteristics of a digital attenuator. The digital pad
accommodates both µ255-law and A-law coding. There are 32 combinations
each for µ255 to µ255, µ255 to A-law, A-law to µ255, and A-law to A-law.
These values are selected to meet the EIA loss and level plan.
Table 1 40
Digital pad values and offset allocations
Offset PAD set 0 PAD set 1
00dB -7db
12dB -8db
23dB -9db
34dB -10db
45dB 0.6db
56.1dB 7db
68dB 9db
7-1dB 10db
8-3dB 11db
9-4dB 12db
Aidle code, 7F 3db
Bunassigned code, FF 14db
C1dB spare
D-2dB spare
E-5db spare
F-6db spare