PSB2163T-V31TR Infineon Technologies, PSB2163T-V31TR Datasheet - Page 174

• Manufacturer Part Number: PSB2163T-V31TR
• Description: IC AUDIO RINGING CODEC 28-PDSO
• Manufacturer: Infineon Technologies
• Series: ARCOFI®r

Specifications of PSB2163T-V31TR

• Function: CODEC Filter
• Interface: IOM-2, PCI, Serial
• Number Of Circuits: 1
• Voltage - Supply: 5V
• Current - Supply: 900µA
• Power (watts): 1mW
• Operating Temperature: -25°C ~ 80°C
• Mounting Type: Surface Mount
• Package / Case: DSO-28
• Includes: Activation and Deactivation, B-Channel and D-Channel HDLC Controllers, D-Channel Priority Handler, Monitor Channel Handler
• Lead Free Status / RoHS Status: Request inventory verification / Request inventory verification
• Other names: PSB2163T-V31INTR; PSB2163T-V31TR

Grounding of Microphones
Some transducers as electret microphones for example, always need a reference to
ground and therefore the question arises, which point of the circuit should serve as a
microphone ground.
As long as truly differential signal sources are used, this is not a problem. The high
common mode rejection ratio of the differential microphone inputs eliminates interfering
signals. But if an electret microphone is used, this microphone requires some biasing
and will be tied to ground with one pin (see chapter 3.2 for more examples about
connecting microphones). Figure 2 shows the typical arrangement for connecting
electret microphones. The microphone inputs MIN1/MIP1 and MIN2/MIP2 are
differential inputs with an input impedance of 15 k
required for these inputs. In the unbalanced configuration in figure 2, one of the inputs
is tied to the reference voltage (
very clean DC voltage; a current of up to 1.0 mA can be drawn from
is used externally, it has to be blocked to the analog ground (
capacitor (ceramic). If the
From figure 2 it becomes obvious, that any voltage difference introduced in the circle
marked with a dashed line, will be regarded as a wanted signal and therefore will be
amplified and converted by the ARCOFI-SP. In a real application, only the voltage
originating from the microphone itself has to be amplified. This leads to the requirement,
that the microphone ground must be connected directly to the pin
plane which incorporates
If on a PCB the microphone is not placed directly next to the ARCOFI-SP, it is a good
solution to use a separate ground trace between the microphone and the analog ground
of the ARCOFI-SP. If the microphone is connected via a longer cable, the cable should
be shielded and again the screen is tied to the analog ground.
Summary
• Good decoupling between the pins given in one row of table 1
• Large ground plane underneath the chip connecting all ground pins
• Careful grounding of unsymmetrical signal sources
If these considerations receive attention, the full performance of the PSB 2163 is
available even in a very "noisy" environment.
Semiconductor Group
V
V
SSA
REF
).
pin remains open, no blocking capacitor is required.
V
REF
pin). The reference voltage is a stable (2.4 V) and
Layout and Wiring Recommendations
173
or more. No external biasing is
V
V
V
SSA
SSA
REF
) with a 100nF
(or to a ground
. If the
V
REF
pin