TP3076 Datasheet, PDF (1/18 Pages) National Semiconductor (TI) – COMBO II Programmable PCM CODEC/Filter for ISDN and Digital Phone Applications

April 1994
TP3076
COMBO^® II Programmable PCM CODEC/Filter for ISDN
and Digital Phone Applications
General Description
The TP3076 is a second-generation combined PCM CODEC
and Filter devices optimized for digital switching applications
on subscriber line and trunk cards and digital phone applica-
tions. Using advanced switched capacitor techniques,
COMBO II combines transmit bandpass and receive low-
pass channel filters with a companding PCM encoder and
decoder. The devices are A-law and µ-law selectable and
employ a conventional serial PCM interface capable of being
clocked up to 4.096 MHz. A number of programmable func-
tions may be controlled via a serial control port.
Channel gains are programmable over a 25.4 dB range in
each direction.
To enable COMBO II to interface to the SLIC control leads, a
number of programmable latches are included; each may be
configured as either an input or an output. The TP3076 pro-
vides 4 latches.
Features
n Complete CODEC and Filter system including:
— Transmit and receive PCM channel filters
— µ-law or A-law companding coder and decoder
— Receive power amplifier drives 300Ω
— 4.096 MHz serial PCM data (max)
n Programmable functions:
— Transmit gain: 25.4 dB range, 0.1 dB steps
— Receive gain: 25.4 dB range, 0.1 dB steps
— Time-slot assignment; to 64 slots/frame
— 4 interface latches
— A or µ-law
— Analog loopback
— Digital loopback
n Direct interface to solid-state SLICs
n Standard serial control interface
n 80 mW operating power (typ)
n 1.5 mW standby power (typ)
n Designed for CCITT and LSSGR specifications
n TTL and CMOS compatible digital interfaces
Note: See also AN-614 COMBO II application guide.
Block Diagram
FIGURE 1.
TRI-STATE^® and COMBO^® are registered trademarks of National Semiconductor Corporation.
MICROWIRE/PLUS™ is a trademark of National Semiconductor Corporation.
© 1999 National Semiconductor Corporation DS009758
DS009758-1
www.national.com