PEB2466 SIEMENS [Siemens Semiconductor Group], PEB2466 Datasheet - Page 15

• Manufacturer Part Number: PEB2466
• Description: Four Channel Codec Filter with PCM- and m-Controller Interface SICOFI4-mC
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

The change from 2 m to 1 m CMOS process requires new concepts in the realization
of the analog functions. High performance (in the terms of gain, speed, stability …) 1 m
2
2.1
CMOS devices cannot withstand more than 5.5 V of supply-voltage. On that account the
negative supply voltage VSS of the previous SICOFIs is omitted. This is a benefit for the
user but it makes a very high demand on the analog circuitry.
ADC and DAC are changed to Sigma-Delta-concepts to fulfill the stringent requirements
on the dynamic parameters.
Using 1 m CMOS does not only lead to problems - it is the only acceptable solution in
terms of area and power consumption for the integration of more than two SICOFI
channels on a single chip.
It is rather pointless to implement 4 codec-filter-channels on one chip with pure analog
circuitry. The use of a DSP-concept (the SICOFI and the SICOFI-2-approach) for this
function is a must for an adequate four channel architecture.
Figure 2
SICOFI
Semiconductor Group
®
Functional Description
SICOFI
-4 C Signal Flow Graph (for any channel)
®
-4- C Principles
15
Functional Description
PEB 2466
02.97