TEXAS INSTRUMENTS TCM37C14A, TCM37C15A Technical data

TCM37C14A, TCM37C15A

PCM COMBO WITH PROGRAMMABLE GAIN CONTROL

SLWS018B – JUNE 1996 – REVISED MAY 1998

D

Meet CCITT/(D3/D4) Channel Bank
Recommendations for Input Signals
Greater than –55 dBm0

D

Programmable Transmit and Receive Gain
Control With Pin-Selectable
Gain/Attenuation Levels

D

Includes Differential Output on the
TCM37C14A

D

Precision Switched-Capacitor Filters and
Converters

D

Improved Version TCM29C13A Series
COMBOs (CODEC and Filters)

D

Low Power CMOS
– Operating Mode...70 mW Typical
– Power-Down Mode...7 mW Typical

D

Internal Sample-and-Hold and Autozero
Functions

D

Precision Internal Voltage References

D

TCM37C14A Features Pin-Selectable µ-Law
or A-Law Companding and Pin-Selectable
Master Clock Rate (1.536 MHz, 1.544 MHz,
and 2.048 MHz Available)

D

TCM37C15A is 2.048 MHz A-Law Only

description

V

BB

PWRO+

RIN
RS1
RS2

GSR

GS1
GS0

PCMIN

FSR

V

BB

PWRO+

PWRO–

RIN
RS1
RS2

GSR

GS1
GS0

CLKSEL

PCMIN

FSR

TCM37C15A ...DW OR N PACKAGE

TCM37C14A ...DW PACKAGE

(TOP VIEW)

1
2
3
4
5
6
7
8
9
10

(TOP VIEW)

1
2
3
4
5
6
7
8
9
10
11
12

20
19
18
17
16
15
14
13
12
11

24
23
22
21
20
19
18
17
16
15
14
13

V

CC

GSX
TS1
TS2
ANLGIN
AGND
PCMOUT
FSX
MCLK
DGND

V

CC

GSX
TS1
TS2
ANLGIN
AGND
TSX
PCMOUT
FSX
ASEL
MCLK
DGND

The TCM37C14A and TCM37C15A PCM combo with programmable gain control devices are single-chip PCM
combos (pulse-code-modulated CODECs with voice-band filtering). They are designed to perform transmit
encoding (A/D conversion) and receive decoding (D/A conversion), as well as the transmit and receive filtering
functions required to meet CCITT/(D3/D4) G.711 and G.714 specifications in a PCM system. Each device
provides all the functions required to interface a full-duplex, 4-line voice telephone circuit with a TDM
(time-division-multiplexed) system, and also perform the encoding and decoding of call progress tones. The
TCM37C14A and TCM37C15A are based on the proven TI TCM29C13A core, and have the added feature of
programmable transmit and receive gain.

Primary applications include line interface for digital transmission and switching of T1/E1 carrier (P ABX [private
branch automatic exchange] and central office telephone systems), subscriber line concentrators, digital
encryption systems, and digital signal processing. They are intended to be used at the analog termination of
a PCM line or trunk to the POTS (plain old telephone system) local-loop line.

The TCM37C15A is available in 20-pin DW SOIC (small-outline IC) or 20-pin N PDIP (plastic dual-in-line
package) packages, and the TCM37C14A is available in a 24-pin DW SOIC package and includes differential
output. All are characterized for operation from –40°C to 85°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 MOS gates.

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

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.

POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

Copyright  1998, Texas Instruments Incorporated

1

TCM37C14A, TCM37C15A

T

A

PCM COMBO WITH PROGRAMMABLE GAIN CONTROL

SLWS018B – JUNE 1996 – REVISED MAY 1998

AVAILABLE OPTIONS

PACKAGE

20 PIN 24 PIN

SMALL OUTLINE

(DW)

–40°C to 85°C TCM37C15AIDW TCM37C15AIN TCM37C14AIDW

functional block diagram

PLASTIC DIP

(N)

SMALL OUTLINE

(DW)

TS1
TS2

ANLGIN

GSX

RIN

GSR

RS1
RS2

PWRO+

PWRO–

Transmit Section

22
21

20

23

4
7
5
6

2

3

†

Gain

Set

Transmit

Third-Order

Antialias

Low-Pass

Filter

(Analog)

Gain

Set

Transmit

Sixth-Order

Low-Pass

Filter

(Switched Cap)

Fc = 3400 Hz

Reference

Filter

(Switched Cap)

Buffer

Auto Zero

Transmit

Third-Order

High-Pass

Filter

Fc = 200 Hz

Analog to

Digital Control

Logic

Digital-to-

Analog

Converter

Sample

and Hold

ADC

Control SectionReceive Section

Digital-to-

Analog Control

Logic

Output

Register

Control

Logic

Input

Register

17

18

16

14

10
15
9
8

11

PCMOUT

†

TSX

FSX

MCLK

CLKSEL

†

ASEL
GS0
GS1

PCMIN

†

24 1 13 19 12

FSRAGNDDGNDVBBVCC

†

TCM37C14A only

NOTE A: Terminal numbers shown are for the TCM37C14A.

2

POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

NAME

TCM37C14A, TCM37C15A

PCM COMBO WITH PROGRAMMABLE GAIN CONTROL

SLWS018B – JUNE 1996 – REVISED MAY 1998

Terminal Functions

TERMINAL

NO.

’37C15A ’37C14A

AGND 15 19 Analog ground return for all internal voice circuits. AGND is connected internally to DGND.
ANLGIN 16 20 I Analog input to transmit operational amplifier.
ASEL 15 I Selection between A-law and µ-law operation. When ASEL is connected to VBB, A-law is selected.

CLKSEL 10 I Clock frequency selection. CLKSEL must be connected to VBB, VCC, or ground to select the master

DGND 11 13 Digital ground for all internal logic circuits. DGND is internally connected to AGND.
FSR 10 12 I Frame-synchronization clock input/time-slot enable for receive channel. The receive channel enters

FSX 13 16 I Frame-synchronization clock input/time-slot enable for transmit. The transmit channel enters the

GS0 8 9 I Input for first bit of the programmable gain control circuitry. GS0 works in combination with GS1 to

GS1 7 8 I Input for second bit of the programmable gain control circuitry . GS1 works in combination with GS0

GSR 6 7 I Input to gain-setting network of the output power amplifier. Gain is set by external resistors with three

GSX 19 23 O Output terminal of internal uncommitted operational amplifier. Internally , GSX is the voice signal input

MCLK 12 14 I Master clock (input). For the TCM37C14A, the master clock frequency can be either 2.048 MHz,

PCMIN 9 11 I Receive PCM input. PCM data is clocked in on PCMIN on eight consecutive negative transitions of

PCMOUT 14 17 O Transmit PCM output. PCM data is clocked out on PCMOUT on eight consecutive positive transitions

PWRO+ 2 2 O Noninverting output of power amplifier. PWRO+ can drive transformer hybrids or high-impedance

PWRO– 3 O Inverting output of power amplifier. PWRO– is functionally identical with and complementary to

RIN 3 4 I Input to receive section amplifiers. (See Figure 6 and Figure 7 for recommended circuitry.)
RS1 4 5 Terminal for first gain-control resistor of the receive section. RS1 is selected through closure of the

RS2 5 6 Terminal for second gain control resistor of the receive section. RS2 is selected through closure of

TS1 18 22 Terminal for gain-control resistor on input of transmit section. TS1 is selected through closure of the

TS2 17 21 Terminal for gain-control resistor on input of transmit section. TS2 is selected through closure of the

TSX 18 O Transmit channel time-slot strobe for the transmit channel (active low). TSX is an open drain output

V

BB

V

CC

1 1 Negative supply voltage. Input is –5 V ± 5%.

20 24 Positive supply voltage. Input is 5 V ± 5%.

I/O DESCRIPTION

When ASEL is connected to VCC or ground, µ-law is selected.

clock frequency. When CLKSEL is tied to VBB, MCLK is 2.048 MHz. When it is tied to ground, MCLK
is at 1.544 MHz. When it is tied to VCC, MCLK is 1.536 MHz.

the standby state when FSR is held low for 300 ms.

standby state when FSX is held low for 300 ms.

simultaneously control transmit and receive gain, and controls power-down instruction. (See
Table 1 and 2 for control logic information.)

to simultaneously control transmit and receive gain, and controls power-down instruction. (See T able
1 and 2 for control logic information.)

levels of programmable gain or attenuation control. (See Figure 6 and Figure 7 for recommended
configuration.)

to the transmit filter.

1.544 MHz, or 1.536 MHz, and is selected by CLKSEL. MCLK for the TCM37C15A is 2.048 MHz.

the receive data clock (MCLK).

of the transmit data clock (MCLK).

loads directly in a differential or a single-ended configuration.

PWRO +.

first gain control switch. (See Figure 6 and Figure 7 for recommended circuitry.)

the second gain control switch. (See Figure 6 and Figure 7 for recommended configuration.)

first gain-control switch. (See Figure 6 and Figure 7 for recommended configuration.)

second gain-control switch. (See Figure 6 and Figure 7 for recommended configuration.)

and can be used as an enable signal for a 3-state output buffer .

POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

3

TCM37C14A, TCM37C15A

Load resistance, R

Load capacitance, C

pF

PCM COMBO WITH PROGRAMMABLE GAIN CONTROL

SLWS018B – JUNE 1996 – REVISED MAY 1998

absolute maximum ratings over operating free-air temperature range (unless otherwise noted)

Supply voltage, V
Supply voltage, V
Voltage range at any analog input, V

(see Note 1) 7 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CC

(see Note 1) –7 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

BB

V

I

+ 0.3 V to V

CC

BB

†

– 0.3 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Continuous total power dissipation at (or below) 25°C free-air temperature 1300 mW. . . . . . . . . . . . . . . . . . .

Operating free-air temperature range, T
Storage temperature range, T

–65°C to 150°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

stg

–40°C to 85°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

A

Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds: DW or N package 260°C. . . . . . . . . . . . . . .

JEDEC Latch up ±250 mA or ±10 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

†

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: Voltage values are with respect to GND.

recommended operating conditions (see Note 2)

MIN NOM MAX UNIT

Supply voltage, VCC (see Notes 2 and 3) 4.75 5 5.25 V
Supply voltage, V
DGND voltage with respect to AGND 0 V
High-level input voltage, V
Low-level input voltage, V

p

Operating free-air temperature, T

NOTES: 2. To avoid possible damage to these CMOS devices and resulting reliability problems, the power-up procedure described in the device

BB

IH

IL

L

L

A

power-up sequence paragraphs later in this document should be followed.

3. Voltages at analog inputs and outputs, VCC and VBB terminals, are with respect to the AGND terminal. All other voltages are
referenced to the DGND terminal unless otherwise noted.

At GSX/GSR 10 kΩ
At PWRO+ and/or PWRO– 300 Ω
At GSX/GSR 50
At PWRO+ and/or PWRO– 100

–4.75 –5 –5.25 V

2.2 V

0.8 V

p

–40 85 °C

4

POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

PARAMETER

TEST CONDITIONS

UNIT

V

CC

V

BB

TCM37C14A, TCM37C15A

PCM COMBO WITH PROGRAMMABLE GAIN CONTROL

SLWS018B – JUNE 1996 – REVISED MAY 1998

electrical characteristics over recommended ranges of supply voltage and operating free-air
temperature (outputs not loaded) (unless otherwise noted)

supply current

0°C to 85°C –40°C to 0°C

MIN TYP MAX MIN TYP MAX

Supply current from

I

CC

Supply current from

I

BB

PDPower dissipation

digital interface

V

High-level output voltage at PCMOUT IOH = –9.6 mA 2.4 V

OH

V

Low-level output voltage at PCMOUT, TSX IOL = 3.2 mA 0.5 V

OL

I

High-level input current, any digital input VI = 2.2 V to V

IH

I

Low-level input current, any digital input VI = 0 to 0.8 V 12 µA

IL

C

Input capacitance 5 pF

i

C

Output capacitance 5 pF

o

†

All typical values are at VBB = –5 V , VCC = 5 V, and TA = 25°C.

Operating 7 10 8 11
Standby FSX, FSR at VIL (after 300 ms) 0.5 1.3 1 1.7
Power down GS0, GS1 = VIL (after 300 ms) 0.5 1.2 1 1.7
Operating –7 –9 –9 –11.5
Standby FSX, FSR at VIL (after 300 ms) –0.6 –1 –0.8 –1.2
Power down GS0, GS1 = VIL (after 300 ms) –0.3 –0.9 –0.4 –1.2
Operating 70 100 80 110
Standby
Power down GS0, GS1 = VIL (after 300 ms) 7 12 10 17

PARAMETER TEST CONDITIONS MIN TYP†MAX UNIT

FSX, FSR at VIL (after 300 ms) 9 13 10 17

CC

mA

mA

mW

12 µA

transmit amplifier input

PARAMETER TEST CONDITIONS MIN TYP†MAX UNIT

Input current at ANLGIN VI = –2.17 V to 2.17 V ±100 nA
Input offset voltage at ANLGIN VI = –2.17 V to 2.17 V ±25 mV
Common-mode rejection at ANLGIN VI = –2.17 V to 2.17 V 55 dB
Open-loop voltage amplification at GSX 5000
Open-loop unity-gain bandwidth at GSX 1 MHz
Input resistance at ANLGIN 10 MΩ

†

All typical values are at VBB = –5 V , VCC = 5 V, and TA = 25°C.

receive filter output‡

PARAMETER MIN TYP†MAX UNIT

Output offset voltage PWRO+, PWRO– (single ended), Relative to AGND 80 mV
Output resistance at PWRO+, PWRO– 1 Ω

†

All typical values are at VBB = –5 V , VCC = 5 V, and TA = 25°C.

‡

PWRO– on TCM37C14A only

POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

5

TCM37C14A, TCM37C15A

R

600 Ω

Zero-transmission-level point, transmit channel (0 dBm0)

dBm

R

900 Ω

R

600 Ω

Zero-transmission-level point, receive channel (0 dBm0)

dBm

R

900 Ω

PCM COMBO WITH PROGRAMMABLE GAIN CONTROL

SLWS018B – JUNE 1996 – REVISED MAY 1998

electrical characteristics over recommended ranges of supply voltage and operating free-air
temperature (outputs not loaded) (unless otherwise noted) (continued)

gain and dynamic range, V

PARAMETER TEST CONDITIONS MIN TYP MAX UNIT

Encoder milliwatt response (transmit gain tolerance)
Encoder milliwatt response variation with temperature and

supplies
Digital milliwatt response (receive gain tolerance) relative to zero-

transmission level point
Digital milliwatt response variation with temperature and supplies TA = –40°C – 85°C, supplies = ±5% ±0.08 dB

p

p

NOTES: 4. Unless otherwise noted, the analog input is a 0-dBm0, 1020-Hz sine wave, where 0 dBm0 is defined as the zero-reference point

of the channel under test with unity gain set on the amplifier. This corresponds to an analog signal input of 1.064 V rms, or an output
of 1.503 Vrms.

5. The input amplifier is set for unity gain, noninverting. The digital input is a PCM bit stream generated by passing a 0-dBm0, 1020-Hz
sine wave through an ideal encoder.

6. Receive output is measured single ended with the output amplifier in the unity-gain configuration. All output levels are (sin x)/x
corrected.

= 5 V, VBB = –5 V, TA = 25°C (see Notes 4, 5, and 6) (unless otherwise noted)

CC

µ-law
A-law
µ-law
A-law
µ-law
A-law
µ-law
A-law

Signal input = 1.064 Vrms for µ-law,
Signal input = 1.068 Vrms for A-law

TA = –40°C – 85°C, supplies = ±5% ±0.08 dB
Signal input per CCITT G.711,

output signal = 1 kHz

=

L

=

L

=

L

=

L

±0.04 ±0.2 dBm0

±0.04 ±0.2 dBm0

2.76

2.79
1

1.03

5.76

5.79
4

4.03

gain tracking, reference level = –10 dBm0

PARAMETER TEST CONDITIONS MIN MAX UNIT

3 > input level ≥ –40 dBm0 ±0.25

Transmit gain tracking error , sinusoidal input

Receive gain tracking error, sinusoidal input

–40 > input level ≥ –50dBm0 ±0.5
–50 > input level ≥ –55 dBm0 ±1.2
3 > input level ≥ –40 dBm0 ±0.25
–40 > input level ≥ –50 dBm0 ±0.5
–50 > input level ≥ –55 dBm0 ±1.2

dB

dB

noise

PARAMETER TEST CONDITIONS MIN TYP†MAX UNIT

Transmit noise, C-message weighted ANLGIN = AGND 1 7 dBrnC0
Transmit noise, psophometrically weighted ANLGIN = AGND –82 –80 dBm0p

Receive noise, C-message-weighted quiet code at PWRO+
Receive noise, psophometrically weighted PCM = lowest positive decode level –81 dBm0p

†

All typical values are at VBB = –5 V , VCC = 5 V, and TA = 25°C.

PCMIN = 11111111 (µ-law),
PCMIN = 11010101 (A-law)

2 5 dBrnC0

6

POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

V

ppl

oltage rejection ratio, transmit channel

200 mV

dB

y

V

ppl

oltage rejection ratio, transmit channel

yg ,

dB

y

CC

ygj ,

yg ,

dB

y

BB

ygj ,

yg ,

dB

dBm0

TCM37C14A, TCM37C15A

PCM COMBO WITH PROGRAMMABLE GAIN CONTROL

SLWS018B – JUNE 1996 – REVISED MAY 1998

electrical characteristics over recommended ranges of supply voltage and operating free-air
temperature (outputs not loaded) (unless otherwise noted) (continued)

power supply rejection and crosstalk attenuation

PARAMETER TEST CONDITIONS MIN TYP†MAX UNIT

pp

su

CC

BB

V
(single ended)

V
(single ended)

Crosstalk attenuation, transmit-to-receive at PWRO+ (single ended)

Crosstalk attenuation, receive-to-transmit at PWRO+ (single ended)

†

All typical values are at VBB = –5 V , VCC = 5 V, and TA = 25°C.

y v

pp

su

y v

supply voltage rejection ratio, receive channel

supply voltage rejection ratio, receive channel

0 < f < 30 kHz
30 < f < 50 kHz

0 < f < 30 kHz

30 < f < 50 kHz

0 < f < 30 kHz

30 < f < 50 kHz

0 < f < 30 kHz

30 < f < 50 kHz

Idle channel,

pp

supply signal =
f measured at PCMOUT

Idle channel,
suppl

signal = 200 mVpp,
f measured at PCMOUT
Idle channel,

Idle channel,
suppl

signal = 200 mVpp,
narrow-band,
f measured at PWRO+

Idle channel,
suppl

signal = 200 mVpp,
narrow-band,
f measured at PWRO+

ANLGIN = 0 dBm0,
f = 1.02 kHz, unity gain,
PCMIN = lowest decode level

PCMIN = 0 dBm0,
f = 1.02 kHz

pp

pp,

–40
–45

–35

–55

–40

–45

–40

–45

75 dB

75 dB

distortion

PARAMETER TEST CONDITIONS MIN MAX UNIT

0 > ANLGIN ≥ –30 dBm0 36

Transmit signal to distortion ratio, sinusoidal input (CCITT G.712 – Method 2)

Receive signal to distortion ratio, sinusoidal input (CCITT G.712 – Method 2)

Transmit single-frequency distortion products Input signal = 0 dBm0 –46 dBm0
Receive single-frequency distortion products Input signal = 0 dBm0 –46 dBm0

Intermodulation distortion, end-to-end
Spurious out-of-band signals, end-to-end

–30 > ANLGIN ≥ –40 dBm0 30

–40 > ANLGIN ≥ –45 dBm0 25

0 > ANLGIN ≥ –30 dBm0 36

–30 > ANLGIN ≥ –40 dBm0 30

–40 > ANLGIN ≥ –45 dBm0 25

CCITT G.712 (7.1) –35

CCITT G.712 (7.2) –49

CCITT G.712 (6.1) –25

CCITT G.712 (9) –40

dB

dB

POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

7