tp3067 National Semiconductor Corporation, tp3067 Datasheet - Page 13

• Manufacturer Part Number: tp3067
• Description: ``enhanced Serial Interface Cmos Codec/filter Combo
• Manufacturer: National Semiconductor Corporation

Applications Information
POWER SUPPLIES
While the pins of the TP3060 family are well protected
against electrical misuse it is recommended that the stan-
dard CMOS practice be followed ensuring that ground is
connected to the device before any other connections are
made In applications where the printed circuit board may be
plugged into a ‘‘hot’’ socket with power and clocks already
present an extra long ground pin in the connector should
be used
All ground connections to each device should meet at a
common point as close as possible to the GNDA pin This
Typical Asynchronous Application
Note 1 Transmit gain
Note 2 Receive gain
e
e
20
20
FIGURE 4
c
c
log
log
13
2
R1
minimizes the interaction of ground return currents flowing
through a common bus impedance 0 1
pling capacitors should be connected from this common
ground point to V
possible
For best performance the ground point of each CODEC
FILTER on a card should be connected to a common card
ground in ‘‘STAR’’ formation rather than via a ground bus
This common ground point should be decoupled to V
V
Note See Application Note 370 for further details
c
R4
R2
BB
a
R3
R2
with 10 F capacitors
R4
(R1
t
10 k
a
R2)
t
CC
10 k
and V
TL H 5070– 5
BB
as close to the device as
F supply decou-
CC
and