
TCM320AC54
MONOLITHIC SERIAL INTERFACE
COMBINED PCM CODEC AND FILTER
SCTS043A – NOVEMBER 1994 – REVISED JUL Y 1996
1
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
D
Complete PCM Codec and Filtering System
Includes:
– Transmit High-Pass and Low-Pass
Filtering
– Receive Low-Pass Filter With (sin x)/x
Correction
– Active RC Noise Filters
– µ-Law Compatible Coder and Decoder
– Internal Precision Voltage Reference
– Serial I/O Interface
– Internal Autozero Circuitry
D
µ-Law Coding
D
DTAD and DSP Interface Codec
D
±5-V Operation
D
Low Operating Power...50 mW Typ
D
Power-Down Standby Mode...3 mW Typ
D
Automatic Power Down
D
TTL- or CMOS-Compatible Digital Interface
D
Maximizes Line Interface Card Circuit
Density
description
The TCM320AC54 is comprised of a single-chip PCM codec (pulse-code-modulated encoder and decoder) and
PCM line filter. This device provides all the functions required to interface a full-duplex (2-wire) voice telephone
circuit with a TDM (time-division-multiplexed) system. Primary applications include:
• Line interface for digital transmission and switching of T1 carrier,
PABX, and central office telephone systems
• Subscriber line concentrators
• Digital-encryption systems
• Digital signal processing
The device is designed to perform the transmit encoding (A/D conversion) and receive decoding (D/A
conversion) as well as the transmit and receive filtering functions in a PCM system. It is intended to be used
at the analog termination of a PCM line or trunk. The device requires two transmit and receive master clocks
that may be asynchronous (1.536 MHz, 1.544 MHz, or 2.048 MHz), transmit and receive data clocks that are
synchronous with the master clock (but can vary from 64 kHz to 2.048 MHz), and transmit and receive
frame-sync pulses. The TCM320AC54 provides the band-pass filtering of the analog signals prior to encoding
and after decoding of voice and call progress tones.
The TCM320AC54 is characterized for operation from 0°C to 70°C.
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the CMOS gates.
Copyright 1996, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
V
BB
ANLG GND
VFRO
V
CC
FSR
DR
BCLKR/CLKSEL
MCLKR/PDN
VFXI+
VFXI–
GSX
TSX
FSX
DX
BCLKX
MCLKX
DW OR N PACKAGE
(TOP VIEW)

TCM320AC54
MONOLITHIC SERIAL INTERFACE
COMBINED PCM CODEC AND FILTER
SCTS043A – NOVEMBER 1994 – REVISED JUL Y 1996
2
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
functional block diagram
R2
GSX
14
V
BB
ANLG GNDV
CC
412
–5 V
FSX
5 V
9 8 10 7 125
MCLKX MCLKR/
PDN
BCLKX BCLKR/
CLKSEL
FSR
TSX
13
Power
Amplifier
Timing and Control
DR
6
CLK
Receive
Regulator
S/H
DAC
RC Active
Filter
11
DX
OE
Transmit
Regulator
A/D
Control
Logic
Comparator
Voltage
Reference
Autozero
Logic
S/H
DAC
SwitchedCapacitor
Band-Pass Filter
RC
Active Filter
3
VFRO
+
–
VFXI+
16
R1
15
VFXI–
Analog
Input
SwitchedCapacitor
Low-Pass Filter

TCM320AC54
MONOLITHIC SERIAL INTERFACE
COMBINED PCM CODEC AND FILTER
SCTS043A – NOVEMBER 1994 – REVISED JUL Y 1996
3
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
Terminal Functions
TERMINAL
ANLG GND 2 Analog ground. All signals are referenced to ANLG GND.
BCLKR/CLKSEL 7 Receive bit (data) clock/clock select terminal for master clock. BCLKR/CLKSEL shifts data into DR after the FSR
leading edge and can vary from 64 kHz to 2.048 MHz. Alternately , BCLKR/CLKSEL can be a logic input that selects
either 1.536 MHz/1.544 MHz or 2.048 MHz for the master clock in the synchronous mode. BCLKX is used for both
transmit and receive directions (see Table 1).
BCLKX 10 Transmit bit (data) clock. BCLKX shifts out the PCM data on DX and can vary from 64 kHz to 2.048 MHz, but must
be synchronous with MCLKX.
DR 6 Receive data input. PCM data is shifted into DR following the FSR leading edge.
DX 11 The 3-state PCM data output that is enabled by FSX
FSR 5 Frame sync clock input for receive channel. FSR is an 8-kHz pulse train that enables BCLKR to shift PCM data in DR
(see Figures 1 and 2 for timing details).
FSX 12 Frame sync clock input for transmit channel. FSX is an 8-kHz pulse train that enables BCLKX to shift out the PCM
data on DX (see Figures 1 and 2 for timing details).
GSX 14 Analog output of the transmit input amplifier. GSX is used to externally set gain.
MCLKR/PDN 8 Receive master clock (must be 1.536 MHz, 1.544 MHz, or 2.048 MHz). MCLKR/PDN may be synchronous with
MCLKX but should be synchronous with MCLKX for best performance. When the input is continuously low, MCLKX
is selected for all internal timing. When the input is continuously high, the device is powered down.
MCLKX 9 Transmit master clock (must be 1.536 MHz, 1.544 MHz, or 2.048 MHz). MCLKX may be asynchronous with MCLKR.
TSX 13 Transmit time-slot strobe. TSX is an open-drain output that pulses low during the encoder time slot.
V
BB
1 Negative power supply. VBB = –5 V ±10%
V
CC
4 Positive power supply. VCC = 5 V ±10%
VFRO 3 Analog output of the receive filter
VFXI+ 16 Noninverting input of the transmit input amplifier
VFXI– 15 Inverting input of the transmit input amplifier

TCM320AC54
MONOLITHIC SERIAL INTERFACE
COMBINED PCM CODEC AND FILTER
SCTS043A – NOVEMBER 1994 – REVISED JUL Y 1996
4
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
†
Supply voltage, V
CC
(see Note 1) 7 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Supply voltage, V
BB
(see Note 1) –7 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Voltage range at any analog input or output V
CC
+0.3 V to VBB –0.3 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Voltage range at any digital input or output V
CC
+0.3 V to ANLG GND –0.3 V. . . . . . . . . . . . . . . . . . . . . . . . . .
Continuous total dissipation See Dissipation Rating Table. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operating free-air temperature range, T
A
0°C to 70°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage temperature range,T
stg
–65°C to 150°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds 260°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
†
Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTE 1: All voltages are with respect to GND.
DISSIPATION RATING TABLE
PACKAGE
TA ≤ 25°C
POWER RATING
DERATING FACTOR
ABOVE TA = 25°C
TA = 70°C
POWER RATING
TA = 85°C
POWER RATING
DW 1025 mW 8.2 mW/°C 656 mW 533 mW
N 1150 mW 9.2 mW/°C 736 mW 598 mW
recommended operating conditions (see Note 2)
MIN NOM MAX UNIT
Supply voltage, V
CC
4.5 5 5.5 V
Supply voltage, V
BB
–4.5 –5 –5.5 V
High-level input voltage, V
IH
2.2 V
Low-level input voltage, V
IL
0.6 V
Common-mode input voltage range, V
ICR
‡
±2.5 V
Load resistance, GSX, R
L
10 kΩ
Load capacitance, GSX, C
L
50 pF
Operating free-air temperature, T
A
0 70 °C
‡
Measured with CMRR > 60 dB.
NOTE 2: T o avoid possible damage to these CMOS devices and resulting reliability problems, the power-up procedure described in the device
power-up sequence paragraphs later in this document should be followed.
electrical characteristics over recommended ranges of supply voltage and operating free-air
temperature
supply current
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT

TCM320AC54
MONOLITHIC SERIAL INTERFACE
COMBINED PCM CODEC AND FILTER
SCTS043A – NOVEMBER 1994 – REVISED JUL Y 1996
5
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
electrical characteristics at VCC = 5 V±5%, V
BB
= –5 V±5%, GND at 0 V , T
A
= 25°C (unless otherwise
noted)
digital interface
PARAMETER TEST CONDITIONS MIN MAX UNIT
V
OH
High-level output voltage DX IH = –3.2 mA 2.4 V
VOLLow-level output voltage
TSX IL = 3.2 mA, Drain open 0.4
I
IH
High-level input current VI = VIH to V
CC
±15 µA
I
IL
Low-level input current All digital inputs VI = GND to V
IL
±15 µA
V
OL
Output current in high-impedance state DX VO = GND to V
CC
±15 µA
analog interface with transmit amplifier input
PARAMETER TEST CONDITIONS MIN TYP†MAX UNIT
I
I
Input current VFXI+ or VFXI – VI = –2.5 V to 2.5 V ±200 nA
r
i
Input resistance VFXI+ or VFXI – VI = –2.5 V to 2.5 V 10 MΩ
r
o
Output resistance Closed loop 1 3 Ω
Output dynamic range GSX RL ≥ 10 kΩ ±2.8 V
A
V
Open-loop voltage amplification VFXI+ to GSX 5000
B
I
Unity-gain bandwidth GSX 1 2 MHz
V
IO
Input offset voltage VFXI+ or VFXI – ±20 mV
CMRR Common-mode rejection ratio 60 dB
K
SVR
Supply-voltage rejection ratio 60 dB
†
All typical values are at VCC = 5 V, VBB = –5 V, and TA = 25
°C.
analog interface with receive filter
PARAMETER TEST CONDITIONS MIN TYP†MAX UNIT
Output resistance VFRO 1 3 Ω
Load resistance VFRO = ±2.5 V 600 Ω
Load capacitance VFRO to GND 500 pF
Output dc offset voltage VFRO to GND ±200 mV
†
All typical values are at VCC = 5 V, VBB = –5 V, and TA = 25°C.

TCM320AC54
MONOLITHIC SERIAL INTERFACE
COMBINED PCM CODEC AND FILTER
SCTS043A – NOVEMBER 1994 – REVISED JUL Y 1996
6
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
operating characteristics, V
CC
= 5 V ±5%, VBB = –5 V ±5%, GND at 0 V, V
I
= 1.2276 V, f = 1.02 kHz,
T
A
= 0°C to 70°C, transmit input amplifier connected for unity gain, noninverting (unless otherwise
noted)
timing requirements
TEST CONDITIONS MIN TYP†MAX UNIT
f
clock(M)
Frequency of master clock (see Table 1)
MCLKX
and
MCLKR
Depends on BCLKX/CLKSEL
1.536
1.544
2.048
MHz
f
clock(B)
Frequency of bit clock, transmit BCLKX 64 2.048 kHz
t
w1
Pulse duration, MCLKX and MCLKR high 160 ns
t
w2
Pulse duration, MCLKX and MCLKR low 160 ns
t
r1
Rise time of master clock
MCLKX
and
MCLKR
50 ns
t
f1
Fall time of master clock
MCLKX
and
MCLKR
50 ns
t
r2
Rise time of bit clock, transmit BCLKX
50 ns
t
f2
Fall time of bit clock, transmit BCLKX
50 ns
t
su1
Setup time, BCLKX high (and FSX in long-frame
sync mode) before MCLKX↓
First bit clock after the leading
edge of FSX
100 ns
t
w3
Pulse duration, BCLKX and BCLKR high VIH = 2.2 V 160 ns
t
w4
Pulse duration, BCLKX and BCLKR low VIL = 0.6 V 160 ns
t
h1
Hold time, frame sync low after bit clock low
(long frame only)
0 ns
t
h2
Hold time, BCLKX high after frame sync↑
(short frame only)
0 ns
t
su2
Setup time, frame sync high before bit clock↓
(long frame only)
80 ns
t
d1
Delay time, BCLKX high to data valid Load = 150 pF plus 2 LSTTL loads
‡
0 140 ns
t
d2
Delay time, BCLKX high to TSX low Load = 150 pF plus 2 LSTTL loads
‡
140 ns
t
d3
Delay time, BCLKX (or 8 clock FSX in long frame
only) low to data output disabled
50 165 ns
t
d4
Delay time, FSX or BCLKX high to data valid
(long frame only)
CL = 0 pF to 150 pF 20 165 ns
t
su3
Setup time, DR valid before BCLKR↓ 50 ns
t
h3
Hold time, DR valid after BCLKR or BCLKX↓ 50 ns
t
su4
Setup time, FSR or FSX high before
BCLKR or BCLKR↓
Short-frame sync pulse (1 or 2 bit
clock periods long) (see Note 3)
50 ns
t
h4
Hold time, FSX or FSR high after
BCLKX or BCLKR↓
Short-frame sync pulse (1 or 2 bit
clock periods long) (see Note 3)
100 ns
t
h5
Hold time, frame sync high after bit clock↓
Long-frame sync pulse (from 3 to 8 bit
clock periods long)
100 ns
t
w5
Minimum pulse duration of the frame sync
pulse (low level)
64-kbps operating mode 160 ns
†
All typical values are at VCC = 5 V, VBB = –5 V, and TA = 25°C.
‡
Nominal input value for an LSTTL load is 18 kΩ.
NOTE 3: For short-frame sync timing, FSR and FSX must go high while their respective bit clocks are high.