SGS Thomson Microelectronics TS616IDWT, TS616IDW, TS616 Datasheet

TS616
DUAL WIDE BAND OPERATIONAL AMPLIFIER
WITH HIGH OUTPUT CURRENT
LOW NOISE : 2.5nV/Hz
HIGH OUTPUT CURRENT : 420mA
VERY LOW HARMONIC AND INTERMODU-
LATION D I S TORTIO N
HIGH SLEW RA TE : 420V/µs
-3dB BANDWIDTH : 40MHz@gain=12dB on
25load single ended.
on 50load, 12V power supply
CURRENT FEEDBACK STRUCTURE
5V to 12V POWER SUPPLY
SPECIFIED FOR 20 and 50
DIFFERENTIAL LOAD
DESCRIPTION
The TS616 is a dual operational am plifier featur­ing a high output current o f 410m A. T he drivers can be configured differentially for driving signals in telecommunication systems using multiple car­riers. The TS616 is ideally suited for xDSL (High Speed Asymmetrical Digital Subscriber Line) ap­plications. This circuit is c apable of driving a 10 or 25 load at ±2.5V, 5V, ±6V or +12V power supply. The TS616 is able to reach a -3dB band­width of 40MHz on 25 load with a 12dB gain. This device is designed for high slew rates sup­porting low harmonic distortion and intermodula­tion.
DW
SO8 Exposed-Pad
(Plastic Micro package)
ORDER CODE
Part Number Temperature Range Package
TS616IDW -40, +85°C DW TS616IDWT -40, +85°C DW
DW = Small Outline Package with Exposed-Pad, T = Tape & Real
PIN CONNECTIONS (top view)
Output1
Output1
1
1 2
VCC -
VCC -
2
-
-
+
+
3
3 4
4
Inverting Input1 Output2
Inverting Input1 Output2
Non Inverting Input1
Non Inverting Input1
VCC +
VCC +
8
8 7
7
Inverting Input2
Inverting Input2
6
6
-
-
+
+
Non Inverting Input2
Non Inverting Input2
5
5
APPLICATION
Line driver for xDSL
Multiple Video Line Driver
December 2002
Cross Section View Showing Exposed-Pad
Cross Section View Showing Exposed-Pad
This pad can be connected to a (-Vcc) copper area on the PCB
This pad can be connected to a (-Vcc) copper area on the PCB
1/27
TS616
ABSOLUTE MAXIMUM RATINGS
Symbol Parameter Value Unit
V
T
T
R R P
ESD
only pins 1, 4, 7, 8
ESD
only pins 2, 3, 5, 6
Supply voltage
CC
V
Differential Input Voltage
id
V
Input Voltage Range
in
Operating Free Air Temperature Range -40 to + 85 °C
oper
Storage Temperature -65 to +150 °C
std
T
Maximum Junction Temperature 150 °C
j
Thermal Resistance Junction to Case 16 °C/W
thjc
Thermal Resistance Junction to Ambient Area 60 °C/W
thja
Maximum Power Dissipation (@Ta=25°C) for Tj=150°C 2 W
max.
CDM : Charged Device Model HBM : Human Body Model MM : Machine Model
CDM : Charged Device Model HBM : Human Body Model MM : Machine Model Output Short Circuit
1. All voltage values, except differential voltage are with respect to network terminal.
2. Differential voltage are non-inverting input terminal with respect to the inverting input terminal.
3. The magnitude of input and output voltage must never exceed V
4. An output current limitation protects the circuit from transient currents. Short-circuits can cause excessive heating. Destructive dissipation can result from short circuit on amplifiers.
1)
2)
3)
±7 V ±2 V ±6 V
1.5 2
200
1.5 2
100
4)
+0.3V.
CC
kV kV
V
kV kV
V
OPERATING CONDITIONS
Symbol Parameter Value Unit
V
V
Power Supply Voltage ±2.5 to ±6 V
CC
+1.5V to +VCC-1.5V
Common Mode Input Voltage
icm
-V
CC
TYPICAL APPLICATION:
Differential Line Driver for xDSL Applications
8
8
3
3
2
2
Vi
Vi
Vi
Vi
R1
R1
R4
R4
Vi Vo
Vi Vo
Vi Vo
Vi Vo
4
4
5
5
+
+
+
+
1/2TS615
1/2TS616
1/2TS615
1/2TS616
_
_
_
_
R2
R2
GND
GND
R3
R3
_
_
_
_
1/2TS615
1/2TS616
1/2TS615
1/2TS616
+
+
+
+
4
4
+Vcc
+Vcc
+Vcc
+Vcc
-Vcc
-Vcc
-Vcc
-Vcc
12.5
12.5
12.5
12.5
1
1
1
1
Vo
Vo
Vo
12.5
12.5
12.5
12.5
Vo
25
25
25
25
1:2
1:2
1:2
1:2
100
100
100
100
V
2/27
TS616
ELECTRICAL CHARACTERISTICS
V
= ±6Volts, Rfb=910,T
CC
Note: As described on page 24 (table 71), the TS616 requires a 620Ω feedback resistor for an optimized bandwidth with a gain of 12B for a 12V power supply. Nevertheless, due to production test constraints, the TS616 is tested with the same feedback resistor for 12V and 5V power su ppl i es (910Ω).
Symbol Parameter Test Condition Min. Typ. Max. Unit
DC PERFORMANCE
V
Input Offset Voltage
io
V
Z
C
CMR
SVR
Differential Input Offset Voltage
io
I
Positive Input Bias Current
ib+
I
Negative Input Bias Current
ib-
Input(+) Impedance 82 k
IN+
Z
Input(-) Impedance 54
IN-
Input(+) Capacitance 1 pF
IN+
Common Mode Rejection Ratio 20 log (∆V
/∆Vio)
ic
Supply Voltage Rejection Ratio 20 log (∆V
I
Total Supply Current per Operator No load 13.5 17 mA
CC
/∆Vio)
cc
DYNAMIC PERFORMANCE and OUTPUT CHARACTERISTIC
R
Open Loop Transimpedance
OL
-3dB Bandwidth
Full Power Bandwidth
BW
Gain Flatness @ 0.1dB
Tr Rise Time
Tf Fall Time
Ts Settling Time
SR Slew Rate
V
High Level Output Voltage
OH
V
Low Level Output Voltage
OL
Output Sink Current
I
out
Output Source Current
= 25°C (unless otherwise specified)
amb
T
amb
< T
T
min.
T
amb
T
amb
T
min.
T
amb
T
min.
V
ic
T
min.
V
cc
T
min.
V
out
T
min.
< T
amb
= 25°C
< T
< T
amb
< T
< T
amb
= ±4.5V
< T
< T
amb
=±2.5V to ±6V < T
< T
amb
= 7Vp-p, RL = 25
< T
amb.
Small Signal V A
= 12dB, RL = 25
V
Large Signal V
= 12dB, RL = 25
A
V
Small Signal V
= 12dB, RL = 25
A
V
V
= 6Vp-p, AV = 12dB, RL
out
= 25
= 6Vp-p, AV = 12dB, RL
V
out
= 25
= 6Vp-p, AV = 12dB, RL
V
out
= 25
= 6Vp-p, AV = 12dB, RL
V
out
= 25
R
=25Ω Connected to GND
L
R
=25Ω Connected to GND
L
V
= -4Vp
out
< T
T
min.
V
out
T
min.
amb
= +4Vp
< T
amb
< T
< T
< T
max.
max.
max.
max.
max.
max.
<20mVp
out
=3Vp
out
<20mVp
out
max.
max.
1 3.5
1.6
mV
2.5 mV
530
7.2 315
3.1
A
µ
A
µ
58 64
62
72 81
80
5 13.5
5.7
dB
dB
M
25 40
MHz
26
7 MHz
10.6 ns
12.2 ns
50 ns
330 420 V/µs
4.8 5.05 V
-5.3 -5.1 V
-320 -490
-395
330 420
mA
370
3/27
TS616
Note: As described on page 24 (table 71), the TS616 requires a 620Ω feedback resistor for an optimized bandwidth with a gain of 12B for
a 12V power supply. Nevertheless, due to production test constraints, the TS616 is tested with the same feedback resistor for 12V and 5V power su ppl i es (910Ω).
Symbol Parameter Test Condition Min. Typ. Max. Unit
NOISE AND DISTORTION
eN Equivalent Input Noise Voltage F = 100kHz 2.5 nV/√Hz iNp Equivalent Input Noise Current (+) F = 100kHz 15 pA/√Hz iNn Equivalent Input Noise Current (-) F = 100kHz 21 pA/√Hz
= 14Vp-p, AV = 12dB
HD2
HD3
IM2
IM3
2nd Harmonic Distortion (differential configuration)
3rd Harmonic Distortion (differential configuration)
2nd Order Intermodulation Product (differential configuration)
3rd Order Intermodulation Produ ct (differential configuration)
V
out
F= 110kHz, R
= 14Vp-p, AV = 12dB
V
out
F= 110kHz, R
= 50Ω diff.
L
= 50Ω diff.
L
F1= 100kHz, F2 = 110kHz
= 16Vp-p, AV = 12dB
V
out
= 50Ω diff.
R
L
F1= 370kHz, F2 = 400kHz
= 16Vp-p, AV = 12dB
V
out
R
= 50Ω diff.
L
F1 = 100kHz, F2 = 110kHz
= 16Vp-p, AV = 12dB
V
out
= 50Ω diff.
R
L
F1 = 370kHz, F2 = 400kHz
= 16Vp-p, AV = 12dB
V
out
= 50Ω diff.
R
L
-87 dBc
-83 dBc
-76 dBc
-75
-88 dBc
-87
4/27
TS616
ELECTRICAL CHARACTERISTICS
V
= ±2.5Volts, Rfb=910,T
CC
Symbol Parameter Test Condition Min. Typ. Max. Unit
DC PERFORMANCE
V
Input Offset Voltage
io
V
Z
C
CMR
SVR
Differential Input Offset Voltage
io
I
Positive Input Bias Current
ib+
I
Negative Input Bias Current
ib-
Input(+) Impedance 71 k
IN+
Z
Input(-) Impedance 62
IN-
Input(+) Capacitance 1.5 pF
IN+
Common Mode Rejection Ratio 20 log (∆V
/∆Vio)
ic
Supply Voltage Rejection Ratio 20 log (∆V
I
Total Supply Current per Operator No load 11.5 15 mA
CC
/∆Vio)
cc
DYNAMIC PERFORMANCE and OUTPUT CHARACTERISTICS
R
Open Loop Transimpedance
OL
-3dB Bandwidth
BW
Full Power Bandwidth
Gain Flatness @ 0.1dB
Tr Rise Time
Tf Fall Time
Ts Settling Time
SR Slew Rate
V
High Level Output Voltage
OH
V
Low Level Output Voltage
OL
Output Sink Current
I
out
Output Source Current
= 25°C (unless otherwise specified)
amb
T
amb
< T
T
min.
T
amb
T
amb
T
min.
T
amb
T
min.
V
ic
T
min.
V
cc
T
min.
V
out
T
min.
< T
amb
= 25°C
< T
< T
amb
< T
< T
amb
= ±1V
< T
< T
amb.
=±2V to ±2.5V < T
< T
amb.
= 2Vp-p, RL = 10
< T
< T
amb.
Small Signal V
= 12dB, RL = 10
A
V
Large Signal V
= 12dB, RL = 10
A
V
Small Signal V A
= 12dB, RL = 10
V
V
= 2.8Vp-p, AV = 12dB
out
= 10
R
L
V
= 2.8Vp-p, AV = 12dB
out
= 10
R
L
= 2.2Vp-p, AV = 12dB
V
out
= 10
R
L
= 2.2Vp-p, AV = 12dB
V
out
R
= 10
L
R
=10Ω Connected to GND
L
R
=10Ω Connected to GND
L
= -1.25Vp
V
out
< T
T
min.
V
out
T
min.
< T
amb
= +1.25Vp
< T
< T
amb
max.
max.
max.
max.
max.
max.
<20mVp
out
= 1.4Vp
out
<20mVp
out
max.
max.
0.2 2.5
1
2.5 mV 430 7
1.1 11
1.2
55 61
60
63 79
78
24.2
1.5
20 28
MHz
20
5.7 MHz
11 ns
11.5 ns
39 ns
100 130 V/µs
1.5 1.7 V
-1.9 -1.7 V
-300 -400
-360
200 270
240
mV
A
µ
A
µ
dB
dB
M
mA
5/27
TS616
Symbol Parameter Test Condition Min. Typ. Max. Unit
NOISE AND DISTORTION
eN Equivalent Input Noise Voltage F = 100kHz 2.5 nV/√Hz iNp Equivalent Input Noise Current (+) F = 100kHz 15 pA/√Hz iNn Equivalent Input Noise Current (-) F = 100kHz 21 pA/√Hz
= 6Vp-p, AV = 12dB
HD2
HD3
IM2
IM3
2nd Harmonic Distortion (differential configuration)
3rd Harmonic Distortion (differential configuration)
2nd Order Intermodulation Product (differential configuration)
3rd Order Intermodulation Produ ct (differential configuration)
V
out
F= 110kHz, R
= 6Vp-p, AV = 12dB
V
out
F= 110kHz, R
= 20Ω diff.
L
= 20Ω diff.
L
F1= 100kHz, F2 = 110kHz
= 6Vp-p, AV = 12dB
V
out
R
= 20Ω diff.
L
F1= 370kHz, F2 = 400kHz V
= 6Vp-p, AV = 12dB
out
= 20Ω diff.
R
L
F1 = 100kHz, F2 = 110kHz
= 6Vp-p, AV = 12dB
V
out
= 20Ω diff.
R
L
F1 = 370kHz, F2 = 400kHz V
= 6Vp-p, AV = 12dB
out
R
= 20Ω diff.
L
-97 dBc
-98 dBc
-86
-88
-90
-85
dBc
dBc
6/27
TS616
Figure 1: Load Configuration
Load: RL=25Ω, VCC=±6V
+6V
TS616
TS616
+6V
-6V
-6V
+
+
_
_
25
25
50
50
cable
49.9
49.9
33
33 1W
1W
cable
Figure 2: Closed Loop Gain vs. Frequency
AV=+1
2
0
-2
-4
-6
-8
(gain (dB)
-10
-12
-14
(Vcc=±2.5V, Rfb=1.1k, Rload=10) (Vcc=±6V, Rfb=750
-16 100 1k 10k 100k 1M 10M 100M
gain
phase
, Rload=25Ω)
Frequency (Hz)
(Vcc=±6V)
(Vcc=±2.5V)
(Vcc=±2.5V)
(Vcc=±6V)
50
50
40
20
0
-20
-40
-60
-80
-100
-120
Figure 4: Load Configuration
Load: RL=10Ω, VCC=±2.5V
+2.5V
TS616
TS616
+2.5V
-2.5V
-2.5V
10
10
+
+
_
_
11
11
0.5W
0.5W
49.9
49.9
Figure 5: Closed Loop Gain vs. Frequency
AV=-1
2
0
-2
)
°
Phase (
-4
-6
-8
(gain (dB))
-10
-12
-14
(Vcc=±2.5V, Rfb=1k, Rin=1k, Rload=10) (Vcc=±6V, Rfb=680
-16 100 1k 10k 100k 1M 10M 100M
gain
phase
(Vcc=±2.5V)
, Rin=680, Rload=25Ω)
Frequency (Hz)
(Vcc=±2.5V)
(Vcc=±6V)
50
50
cable
cable
(Vcc=±6V)
50
50
-140
-160
-180
-200
-220
-240
-260
-280
-300
)
°
Phase (
Figure 3: Closed Loop Gain vs. Frequency
AV=+2
8
6
4
2
0
-2
(gain (dB))
-4
-6
(Vcc=±2.5V, Rfb=1k, Rload=10)
-8
(Vcc=±6V, Rfb=680
-10 100 1k 10k 100k 1M 10M 100M
gain
phase
(Vcc=±2.5V)
, Rload=25Ω)
Frequency (Hz)
(Vcc=±6V)
(Vcc=±2.5V)
(Vcc=±6V)
40
20
0
-20
-40
-60
-80
-100
-120
Figure 6: Closed Loop Gain vs. Frequency
AV=-2
8
6
4
)
°
Phase (
2
0
-2
(gain (dB))
-4
-6
(Vcc=±2.5V, Rfb=1k, Rin=510, Rload=10)
-8
(Vcc=±6V, Rfb=680
-10 100 1k 10k 100k 1M 10M 100M
gain
phase
(Vcc=±2.5V)
, Rin=750//620, Rload=25Ω)
Frequen c y (Hz)
(Vcc=±2.5V)
(Vcc=±6V)
(Vcc=±6V)
-140
-160
-180
-200
-220
-240
-260
-280
-300
)
°
Phase (
7/27
TS616
Figure 7: Closed Loop Gain vs. Frequency
AV=+4
14
12
10
8
6
4
(gain (dB))
2
0
-2
(Vcc=±2.5V, Rfb=910, Rg=300, Rload=10) (Vcc=±6V, Rfb=620
-4 100 1k 10k 100k 1M 10M 100M
gain
phase
(Vcc=±2.5V)
(Vcc=±6V)
, R g =560//330Ω, Rload=25Ω)
Frequency (Hz)
(Vcc=±2.5V)
(Vcc=±6V)
Figure 8: Closed Loop Gain vs. Frequency
AV=+8
20
18
16
14
12
10
(gain (dB))
8
6
4
(Vcc=±2.5V, Rfb=680, Rg=240//160, Rload=10) (Vcc=±6V, Rfb=510
2
100 1k 10k 100k 1M 10M 100M
gain
phase
(Vcc=±2.5V)
(Vcc=±6V)
, Rg=270//100, Rload=25Ω)
Frequency (Hz)
(Vcc=±2.5V)
(Vcc=±6V)
40
20
0
-20
-40
-60
-80
-100
-120
40
20
0
-20
-40
-60
-80
-100
-120
)
°
Phase (
Figure 10: Closed Loop Gain vs. Frequency
AV=-4
14
12
10
8
)
°
Phase (
6
4
(gain (dB))
2
0
(Vcc=±2.5V, Rfb=1k, Rin=320//360, Rload=10)
-2
(Vcc=±6V, Rfb=620
-4 100 1k 10k 100k 1M 10M 100M
gain
phase
(Vcc=±2.5V)
(Vcc=±6V)
, Rin=360//270, Rload=25Ω)
Frequency (Hz)
Figure 11: Closed Loop Gain vs. Frequency
AV=-8
20
18
16
14
12
10
(gain (dB))
8
6
4
(Vcc=±2.5V, Rfb=680, Rin=160//180, Rload=10) (Vcc=±6V, Rfb=510
2
100 1k 10k 100k 1M 10M 100M
gain
phase
(Vcc= ± 2. 5V)
(Vcc=±6V)
, Rin=150//110, Rload=25Ω)
Frequency (Hz)
(Vcc=±2.5V)
(Vcc=±6V)
(Vcc=±2.5V)
(Vcc= ± 6V )
-140
-160
-180
-200
-220
-240
-260
-280
-300
-140
-160
-180
-200
-220
-240
-260
-280
-300
)
°
Phase (
)
°
Phase (
Figure 9: Bandwidth vs. Temperature
AV=+4, Rfb=910
50
45
40
35
Bw (MHz)
30
25
20
-40-200 20406080
8/27
Vcc=±6V Load=25
Vcc=±2.5V Load=10
Temperature (°C)
Figure 12: Positive Slew Rate
AV=+4, Rfb=620
4
2
(V)
0
OUT
V
-2
-4
0.0 10.0n 20.0n 30.0n 40.0n 50.0n
, V
=±6V, RL=25
CC
Time (s)
TS616
Figure 13: Positive Slew Rate
AV=+4, Rfb=910
2
1
(V)
0
OUT
V
-1
-2
0.0 10.0n 20.0n 30.0n 40.0n 50.0n
, V
CC
=±2.5V, RL=10
Time (s)
Figure 14: Negative Slew Rate
AV=+4, Rfb=620Ω, VCC=±6V, RL=25
4
2
Figure 16: Positive Slew Rate
AV= - 4, Rfb=620
4
2
(V)
0
OUT
V
-2
-4
0.0 10.0n 20.0n 30.0n 40.0n 50.0n
, V
=±6V, RL=25
CC
Time (s)
Figure 17: Positive Slew Rate
AV= - 4, Rfb=910
2
1
, V
CC
=±2.5V, RL=10
(V)
0
OUT
V
-2
-4
0.0 10.0n 20.0n 30.0n 40.0n 50.0n
Time (s)
Figure 15: Negative Slew Rate
AV=+4, Rfb=910
2
1
(V)
0
OUT
V
-1
-2
0.0 10.0n 20.0n 30.0n 40.0n 50.0n
, V
CC
=±2.5V, RL=10
Time (s)
(V)
0
OUT
V
-1
-2
0.0 10.0n 20.0n 30.0n 40.0n 50.0n
Time (s)
Figure 18: Negative Slew Rate
AV= - 4, Rfb=620Ω, VCC=±6V, RL=25
4
2
(V)
0
OUT
V
-2
-4
0.0 10.0n 20.0n 30.0n 40.0n 50.0n
Time (s)
9/27
TS616
Figure 19: Negative Slew Rate
AV= - 4, Rfb=910
2
(V)
0
OUT
V
-2
0.0 10.0n 20.0n 30.0n 40.0n 50.0n
, V
CC
=±2.5V, RL=10
Time (s)
Figure 20: Slew Rate vs. Temperature
AV=+4, Rfb=910
200
150
100
s)
µ
50
0
-50
Slew Rate (V/
-100
-150
-200
-40-200 20406080
, V
Positive SR
Negative SR
=±2.5V, RL=10
CC
Temperature (°C)
Figure 22: Input Voltage Noise Level
AV=+92, Rfb=910Ω, Input+ connected to Gnd via 10
5.0
+ 6V
+ 6V
+ 6V
+ 6V
+
+
+
+
Output
Output
Output
4.5
Hz)
4.0
3.5
3.0
Input Voltage Noise (nV/
2.5
2.0 100 1k 10k 100k 1M
10
10
10
10
(Frequency (Hz)
Output
_
_
_
_
6V-
6VΩ-
- 6V
- 6V
910
910
910
910
Figure 23: Transimpedance vs. Temperat ure
Open Loop
)
(M R
30
25
Vcc=±6V
20
15
OL
10
Vcc=±2.5V
5
0
-40-200 20406080
Temperature (°C)
Figure 21: Slew Rate vs. Temperature
AV=+4, Rfb=910
600 500 400 300 200
s)
µ
100
0
-100
-200
Slew Rate (V/
-300
-400
-500
-600
-40-200 20406080
10/27
, V
=±6V, RL=25
CC
Positive&Negative SR
Rfb=620
Temperature (°C)
Positive&Negative SR
Rfb=910
Figure 24: Icc vs. Power Supply
Open loop, no load
30
20
10
0
(mA)
CC
I
-10
-20
-30 0123456789101112
Icc(+)
Icc(-)
VCC (V)
TS616
Figure 25: Iib vs. Power Supply
Open loop, no load
7
IB+
6
5
4
A)
µ
(
B
3
I
IB-
2
1
0
5 6 7 8 9 10 11 12
Vcc (V)
Figure 26: I
Open loop, no load
5
4
3
A)
µ
(
IB(-)
2
I
1
0
ib(-) vs. Temperature
Vcc=±6V
Vcc=±2.5V
-40-200 20406080
Temper ature (°C)
Figure 28: I
ib(+) vs. Temperature
Open loop, no load
8
7
6
5
4
A)
µ
(
3
IB(+)
I
2
1
0
-1
-40-200 20406080
Figure 29: V
Open loop, RL=25
6 5 4 3 2
(V)
1
OL
0
& V
-1
OH
V
-2
-3
-4
-5
-6 56789101112
Vcc=±6V
Vcc=±2.5V
Temperature (° C)
oh & Vol vs. Power Supply
VOH
VOL
Vcc (V)
Figure 27: I
cc vs. Temperature
Open loop, no load
14 12 10
Icc(+) for Vcc=±2.5V
8
Icc(+) for Vcc=±6V
6 4 2 0
(mA)
-2
CC
I
-4
-6
Icc(-) for Vcc=±6V
-8
-10
-12
-14
Icc(-) for Vcc=±2.5V
-40-200 20406080
Tem perature ( °C)
Figure 30: V
oh vs. Temperature
Open loop
6
5
4
3
(V)
OH
V
2
1
0
-40-200 20406080
Vcc=±6vV
Load=25
Vcc=±2.5V
Load=10
Temperature (°C)
11/27
TS616
Figure 31: Vol vs. Temperature
Open loop
0
Vcc=±2.5V Load=10
-1
-2
-3
(V)
OL
V
-4
-5
-6
-40-200 20406080
Figure 32: Differential V
Open loop, no load
450
400
350
V)
µ
(
IO
V
300
250
200
-40-200 20406080
Vcc=±6V Load=25
Temperature (°C)
Vcc=±6V
Temperature (°C)
io vs. Temperature
Vcc=±2.5V
Figure 34: CMR vs. Temperature
Open loop, no load
70
68
66
64
62
60
58
CMR (dB)
56
54
52
50
-40-200 20406080
Vcc=±2.5V
Temperature (°C)
Vcc=±6V
Figure 35: SVR vs . Temperature
Open loop, no load
84
82
80
SVR (dB)
78
76
Vcc=±2.5V
-40-200 20406080
Vcc=±6V
Temperature (°C)
Figure 33: V
io vs. Temperature
Open loop, no load
2.0
Vcc=±6V
1.5
1.0
(mV)
IO
V
0.5
0.0
Vcc=±2.5V
-0.5
-40-20 0 20406080
Temperature (°C)
12/27
Figure 36: Iout vs. Temperature
Open loop, VCC=±6V, RL=10Ω
300 250 200 150 100
Isource
50
0
-50
-100
-150
Iout (mA)
-200
-250
-300
-350
-400
-450
Isink
-40-200 20406080
Temperature (°C)
TS616
Figure 37: Iout vs. Temperature
Open loop, VCC=±2.5V, RL=25Ω
300 250 200 150 100
50
Isource
0
-50
-100
-150
Iout (mA)
-200
-250
-300
-350
-400
-450
Isink
-40-200 20406080
Temperature (°C)
Figure 38: Maximum Output Amplitude vs. Load
AV=+4, Rfb=620Ω, VCC=±6V
12
Vcc=±6V
10
Figure 40: Isource vs. Output Amplitude.
VCC=±2.5V, Open Loop, no Load
700
600
500
400
300
Isource (mA)
200
100
0
0.0 0.5 1.0 1.5 2.0 2.5
Vout (V )
Figure 41: Isink vs. Output Amplitude
VCC=±6V, Open Loop, no Load
0
-100
)
8
P-P
(V
6
OUT-MAX
V
4
2
0
0 50 100 150 200
R
()
LOAD
Figure 39: Isink vs. Output Amplitude.
VCC=±2.5V, Open Loop, no Load
0
-100
-200
-300
-400
Isink (mA)
-500
Vcc=±2.5V
-200
-300
-400
Isink (mA)
-500
-600
-700
-6 -5 -4 -3 -2 -1 0
Vout (V)
Figure 42: Isource vs. Output Amplitude
VCC=±6V, Open Loop, no Load
700
600
500
400
300
Isource (mA)
200
-600
-700
-2.5 -2.0 -1.5 -1.0 -0.5 0.0
Vout (V)
100
0
0123456
Vout (V)
13/27
TS616
Figure 43: Group Delay
VCC=±6V, VCC=±2.5V
100
90
80
70
60
50
Delay (ns)
40
30
20
10
300k
1M 10M
Frequency (Hz)
Av=4
Vcc=±6V, Rfb=620, Load= 25 Vcc=±2.5V, Rfb=910, Loa d= 10 IF Bw = 10Hz Smoothing=19.247MHz on 10ns/div scale
50M
SAFE OPERATING AREA Figure 44: Safe Operating Area
100
700
90
Vcc=+/-6V
Ta=25°C
600
80
G=12dB
RL=100
70
500
)
RMS
60
400
(mV
50
Delay (ns)
300
INPUT
V
40
200
30
100
20
10
0
300k
1M 10M 100M
1M 10M
Av=4
Vcc=±6V, Rf b=62 0, Load=25 Vcc=±2.5 V, R f b=91 0, Load = 10 IF Bw = 10Hz Smoothing=19.247MHz on 10ns/div scale
SAFE
OPERATING
AREA
Frequency (Hz)
Frequency (Hz)
50M
Figure 44 shows the safe operating condition. This curve shows the input level vs. the i nput frequen-
cy. It’s necessary to consider this characteristic to guarantee the design . In the dash-lined zone, the consumption increases . Moreover, this increas ed consumption could do dam age to the chip if the temperature increases.
14/27
TS616
INTERMODULATION DISTORTION PRODUCT
Non-ideal output of the amplifier can be described by the following series:
Vout C0C1VinC2V
++ +=
2
in
CnV
n
in
due to non-li nearity in the input-output am plitude transfer, where the input is V DC component, C
) is the fundamental and C
1(Vin
=Asinωt, C0 is the
in
is the amplitude of the harmonics of the output sig-
out
.
nal V A one-frequency (one-tone) input signal contrib-
utes to harmonic distortion. A two-tone input sig­nal contributes to harmonic distortion and inter­modulation product.
The study of the intermodulation/distortionfor a two-tone input signal is the first step in character­izing the driving capability of multi-tone input sig­nals.
In this case :
C
+A
()
2
C
A
+
()
n
VinA
V
outC0C1
+=
tsin B
ω
1
tsin B
ω
1
tsin B
ω
1
A
ω
()
1
2
tsin+
ω
2
n
tsin+
ω
2
tsin+=
ω
2
tsin B
tsin+
ω
2
and :
C+
A
()
1
C
2
2

2+C2AB
cos t B
------- A

2
()
3

C
A
+
3

tsin B
ω
1
2
ω
1
ω1ω
()
+
t
2
C
3

3
------­4

3
tsin B33
ω
1
tsin+
ω
2
2
cos tcos
tcos+
2
ω
2
ω
()
1
tsin+
ω
2
ω
2
In this expression, we recognize the second order intermodulation IM2 by the frequencies (ω and (ω IM3 by the frequencies (2ω
+2ω2) and (ω1+2ω2).
(−ω
1
) and the third order intermodulation
1+ω2
1-ω2
The measurement of the intermodulation product of the driver is achieved by using the driver as a
n
mixer by a summing amplifier configuration. In this way, the non-linearity probl em of an ex ternal m ix­ing device is avoided.
Figure 45: Non-inverting Summing Amplifier for Intermodulation measurem ents
1k
1k
1k
1k
49.9
Vin1
Vin1
1:2
1:2
50 100
50 100
49.9
Vin1
Vin1
1:2
1:2
50 100
50 100
49.9
49.9
49.9
49.9
49.9
49.9
1k
1k
+
+
1/2TS616
1/2TS616
_
_
910
910
300
300
300
300
910
910
_
_
1/2TS616
1/2TS616
1k
1k
+
+
+Vcc
+Vcc
-Vcc
-Vcc
Vout diff.
Vout diff.
49.9
49.9
Rout1
Rout1
Rout2
Rout2
49.9
49.9
The following graphs show the IM2 and the IM3 of the amplifier in different configurations. The two-tone input signal was generat ed by the multi­source generator Marconi 2026. Each tone has the same amplitude. The measurement was per­formed using a HP3585A spectrum analyzer.
1-ω2
), (2ω1+ω2),
2:1
2:1
50
100
100
50
)
3C3A2B
----------------------- -+2
3C3A2B
----------------------- -+
3

A
ω


ω
()

2
 
2
V
outC0C2
3
tsin B
1
1
ω
()
1
C
+
+=
t2A2B
ω
2
1
tsin
-- -– 2
ω
2
2
1
2ω+
tsin
-- ­2
2
n
V
()
n
in

A2B2+
---------------------

2

ω
+
ω1ω
()
ω
()
1
tsin 2AB
1
tsin
2
2ω+
tsin
2
2
tsin++sin+
ω
2
15/27
TS616
Figure 46: Intermodulation vs. Output Amplitude
370kHz & 400kHz, AV=+1.5, Rfb=1kΩ, RL=14Ω diff.,VCC=±2.5V
IM2 30kHz
IM3 1140kHz, 1170kHz
-30
-40
-50
-60
IM3
-70
340kHz, 430kHz
-80
IM2 and IM3 (dBc)
-90
-100 012345678
IM2 770kHz
Differential Output Voltage (Vp-p)
Figure 47: Intermodulation vs. Output Amplitude
370kHz & 400kHz, AV=+1.5, Rfb=1kΩ, RL=28Ω diff.,VCC=±2.5V
IM2 30kHz
IM2 770kHz
IM3 1140kHz, 1170kHz
-30
-40
-50
-60 IM3
340kHz, 430kHz
-70
-80
IM2 and IM3 (dBc)
-90
-100 012345678
Differential Output Voltage (Vp-p)
Figure 49: Intermodulation vs. Load
370kHz & 400kHz, AV=+1.5, Rfb=1kΩ, Vout=6.5Vpp, VCC=±2.5V
-30
-40
-50
-60
-70
-80
IM2 and IM3 (dBc)
-90
-100
-110 0 20 40 60 80 100 120 140 160 180 200
IM3 340kHz, 430kHz, 1140kHz, 1170kHz
IM2 30kHz
IM2 770kHz
Differential Load ()
Figure 50: Intermodulation vs. Output Amplitude
100kHz & 110kHz, AV=+4, Rfb=620Ω, RL=200Ω diff.,VCC=±6V
IM3 320kHz
IM2 210kHz
-30
-40
-50
IM3 90kHz, 120kHz
-60
-70
-80
IM2 and IM3 (dBc)
-90
-100
-110 246810121416182022
IM3 310kHz
Differential Output Voltage (Vp-p)
Figure 48: Intermodulation vs. Gain
370kHz & 400kHz, RL=20Ω diff., Vout=6Vpp, VCC=±2.5V
-30
-40
-50
-60
-70
-80
IM2 and IM3 (dBc)
-90
-100
-110
1.0 1.5 2.0 2.5 3.0 3.5 4.0
IM3 340kHz, 430kHz, 1140kHz, 1170kHz
IM2 30kHz
Closed Lo op Gain (Linear)
16/27
IM2 770kHz
Figure 51: Intermodulation vs. Output Amplitude
100kHz & 110kHz, AV=+4, Rfb=620Ω, RL=50Ω diff., VCC=±6V
-30
-40
-50
-60
-70
-80
IM2 and IM3 (dBc)
-90
-100
-110 2 4 6 8 10121416182022
IM3 90kHz, 120kHz, 310kHz, 320kHz
Differential Output Voltage (Vp -p)
IM2 210kHz
TS616
Figure 52: Intermodulation vs. Frequency Range
AV=+4, Rfb=620Ω, RL=50Ω diff., Vout=16Vp p, VCC=±6V
f1=400kHz f2=430kHz
f1=1MHz f2=1.1MHz
1.1M
-60
Quadratic Summation of all IM2 and IM3 components
generated by each two-tones signal
-65
-70 f1=100kHz
-75
f2=110kHz
(dB)
-80
-85
-90
-95
-100
f1=200kHz f2=230kHz
100k 200k 300k 400k 500k 600k 700k 800k 900k 1M 1M
Frequency (Hz)
Figure 53: Intermodulation vs. Output Amplitude
370kHz & 400kHz, AV=+4, Rfb=620Ω, RL=200Ω diff.,VCC=±6V
-30
-40
-50
-60
-70 IM3
-80
340kHz, 430kHz
IM2 and IM3 (dBc)
-90
IM3 1140kHz, 1170kHz
IM2 770kHz
IM2 30kHz
Figure 54: Intermodulation vs. Output Amplitude
370kHz & 400kHz, AV=+4, Rfb=620Ω, RL=50Ω diff., VCC=±6V
-30
-40
-50
-60
-70
-80
IM2 and IM3 (dBc)
-90
-100
-110 0246810121416182022
IM3 340kHz, 430kHz
Differential Output Voltage (Vp-p)
IM3 1140kHz, 1170kHz
IM2 30kHz
IM2 770kHz
-100
-110 0246810121416182022
Differential Output Voltage (Vp-p)
17/27
TS616
PRINTED CIRCUIT BOARD LAYOUT CONSIDERATIONS
In the ADSL frequency range, printed circuit board parasites can affect the closed-loop performance.
The implementation of a proper ground plane on both sides of the PCB is mandatory to provide low inductance and low resistance common return. The most imp ortant factors affecting gai n f latness and bandwidth are stray capa citances at the out­put and inverting input. To minimize these capaci­tances, the space between signal lines and ground plane should be increased. Feedback components connections must be as short as pos­sible in order to decrease the associated induc­tance which affects high frequency gain errors. It is very important to c hoose the smallest pos sible external components, for example, surface mounted devices (SMD) in order to minimize the size of all DC and AC connections.
THERMAL INFORMATION
The TS616 is housed in an Exposed-Pad plastic package. As depicted in figure 55, this package uses a lead frame upon which the die is mounted. This lead frame is exposed as a thermal pa d on the underside of the package. The thermal contact is direct with the dice. This thermal path provides excellent colling.
Figure 55: Exposed-Pad Package
DICE
DICE
Bottom View
Side View
Side View
Bottom View
DICE
DICE
Cross Section View
Cross Section View
Figure 56: Evaluation Board
1
1
The thermal pad is electrically isolated from all pins in the package. It should be soldered to a copper area o f th e PC B underneath the package. Through these thermal paths within this copper ar­ea, heat can b e conducted away from the pack ­age. In this case, the copp er area should be con­nected to (-
V
).
CC
18/27
Figure 57: Schematic Diagram
J205
J205
J205
J206
J206
J206
J207
J207
J207
J208
J208
J208
J209
J209
J209
R206
R206
R206
3
3
R207
R207
R207
R202 R201
R202 R201
R202 R201
R203
R203
R203
R208
R208
R208
R209
R209
R209
R204
R204
R204
R210
R210
R210
R205
R205
R205
3
+
+
+
1/2TS616
1/2TS616
1/2TS616
_
_
_
1
1
1
2
2
2
R214
R214
R214
R211
R211
R211
R212
R212
R212
R215
R215
R215
6
6
6
_
_
_
1/2TS616
1/2TS616
1/2TS616
7
7
7
+
+
+
5
5
5
R213
R213
R213
TS616
Non-Inverting
Non-Inver ti ng
3
R207
J206
R218
R218
R218
R216
R216
R216
R219
R219
R219
R217
R217
R217
J210
J210
J210
R220
R220
R220
J211
J211
J211
R221
R221
R221
J206
Inverting
Inverting
J208
J208
Summing Am plifier
Summing Am plifier
R207
R202
R202
R209
R209
R204
R204
3
+
+
1/2TS616
1/2TS616
_
_
1
1
2
2
R214
R214
R211
R211
R215
R215
_
_
6
6
1/2TS616
1/2TS616
7
7
+
+
5
5
R213
R213
R218
R218
R216
R216
R219
R219
R217
R217
J210
J210
R220
R220
J211
J211
R221
R221
Differential Amplifier
Differential Amplifier
Differential Amplifier
J206
J206
J206
R202
R202
R202
J209
J209
J209
R205
R205
R205
R207
R207
R207
R210
R210
R210
J205
J205
J206
J206
3
3
3
+
+
+
1/2TS616
1/2TS616
1/2TS616
_
_
_
1
1
1
2
2
2
R214
R214
R214
R211
R211
R211
R212
R212
R212
R215
R215
R215
6
6
6
_
_
_
1/2TS616
1/2TS616
1/2TS616
7
7
7
+
+
+
5
5
5
R213
R213
R213
R218
R218
R218
R216
R216
R216
R219
R219
R219
R217
R217
R217
J210
J210
J210
R220
R220
R220
Power Supply
Power Supply
Power Supply
J211
J211
J211
R221
R221
R221
J201
J201
J201
J201 +Vcc
+Vcc
+Vcc
+Vcc J202
J202
J202
J202 GND
GND
GND
GND J303
J303
J303
J303
-Vcc
-Vcc
-Vcc
-Vcc
J20412
J20412
J20412
J20412
R206
R206
3
R207
R207
R202 R201
R202 R201
C202
C202
C202
C202
100nF
100nF
100nF
100nF
C203
C203
C203
C203
C203
100nF
100nF
100nF
100nF
100nF
3
3
3
3
3
+
+
1/2TS616
1/2TS616
_
_
1
1
2
2
R214
R214
R211
R211
+Vcc
+Vcc
+Vcc
+Vcc
C205
C205
C205
C205
+Vcc
+Vcc
+Vcc
+Vcc
100nF
100nF
100nF
C201
C201
C201
C201
100uF
100uF
100uF
100uF
C204
C204
C204
C204
100uF
100uF
100uF
100uF
+Vcc
+Vcc
+Vcc
+Vcc
-Vcc
-Vcc
-Vcc
-Vcc
100nF
8
8
8
8
3
3
3
3
+
+
+
+
1/2TS616
1/2TS616
1/2TS616
1/2TS616
_
_
_
_
2
2
2
2
4
4
4
4
C206
C206
C206
C206
100nF
100nF
100nF
100nF
-Vcc
-Vcc
-Vcc
-Vcc
-Vcc
-Vcc
-Vcc
-Vcc
_
_
_
_
6
6
6
6
1/2TS616
1/2TS616
1/2TS616
1/2TS616
+
+
+
+
5
5
5
5
R218
R218
R216
R216
1
1
1
1
-Vcc
-Vcc
-Vcc
-Vcc-Vcc
Exposed-Pad
Exposed-Pad
Exposed-Pad
Exposed-Pad
7
7
7
7
J210
J210
R220
R220
19/27
TS616
Figure 58: Component Locations - Top Side
Figure 59: Component Locations - Bottom Side
Figure 60: Top Side Board Layout
Figure 61: Bottom Side Board Layout
20/27
TS616
g
NOISE MEASUREMENT Figure 62: Noise Model
+
eN
eN
+
TS616
TS616
_
_
R2
R2
iN+
N3
N3
iN+
iN-
iN-
N2
N2
R1
R1
N1
N1
R3
R3
output
output
HP3577
HP3577 Input noise:
Input noise: 8nV/Hz
8nV/Hz
eN : input voltage noise of the amplifier iNn : negative input current noise of the amplifier iNp : positive input current noise of the amplifier The closed loop gain is :
R
AVg1
The six noise sources are :
=
V1eN
×
fb
--------- -+== R
2
R

------ -
1
+

1
R
k is the Boltzmann’s constant, equal to
1,374.10-23J/°K. T is the temperature (°K). The output noise eNo is c alculated using the Su-
perposition Theorem. However it is not the simple sum of all noi se sources. The squ are root of the sum of the square of each noise source.
eNo V12V22V32V42V52V6
+++++ eq1
2
,=
()
2
2
=
eNo2eN2g2iNn2R
2
2
R

------ -
+

4
× eq2(),
1
R
+
× R
kTR
14
21
++
kTR
2
+
×
iNp
2
R

-------
+

1
R
× g
2
4
kTR
×
2
3
3
The input noise of the instrumentation must be ex­tracted from the measured noise value. Th e real output noise value of the driver is:
eNo Measured
()
2
instrumentation
eq3
()
2
,=
()
The input noise is called the Equivalent Input Noise as it is not directly measured but it is evalu­ated from the meas urement of the output divided by the closed loop gain (eNo/g). After simplification of the fourth and the fifth term of (eq2) we obtain:
2
2
=
eNo2eN2g2iNn2R
+
g4kTR
× eq4(),
+
× R
21
×
2
R

------ -
+
+

1
R
2
+
iNp
2
4
kTR
×
3
× g
3
2
2
=
V
iNn R2×
2
R

-------
+
××

1
R
4
1
kTR
2=
kTR
4
3=
kTR
=
V3iNp R
2
R
------ -
4
=
V
61
V
1
R
54
V

+

31
×
2
R
------ -
1
R
We assume that the thermal noise of a resistance R is:
4kTRF
wher F is the specified bandwidth. On 1Hz bandwidth the thermal noise is reduced to
4kTR
Measurement of eN:
We assume a short-circuit on the non-inverting in­put (R3=0). (eq4) comes:
=
eNo eN2g2iNn2R
+
× eq5(),
×
2
+
g4kTR
2
×
2
In order to easily extract the value of eN, the resis­tance R2 will be chosen as low as possible. In the other hand, the gain must be large enough. R1=10Ω, R2=910Ω, R3=0, Gai n=92 Equivalent Input Noise: 2.57nV/Hz
Input Voltage Noise: eN=2.5nV/√Hz Measurement of iNn:
R3=0 and the output noise equation is still the (eq5). This time the gain must be decreased to de­crease the thermal noise contribution. R1=100Ω, R2=910Ω, R3=0, Gain=10.1 Equivalent Input Noise: 3.40nV/Hz
Negative Input Current Noise: iNn =21pA/Hz Measurement of iNp:
To extract iNp from (eq3), a resist ance R3 is con­nected to the non-inverting input. The val ue of R3 must be chose n in o rder to keep i ts therm al noise
21/27
TS616
+
-VCC
+VCC
10µF
+
10nF
TS616
10µF +
10nF
-
+
-VCC
+VCC
10µF
+
10nF
TS616
10µF +
10nF
-
contribution as low as possible against the iNp contribution. R1=100Ω, R2=910Ω, R3=100Ω, Gain=10.1 Equivalent Input Noise: 3.93nV/Hz
Positive Input Current Noise: iNp=15pA/Hz
Condit i ons: frequency=100kHz, V
Instrumentation: Spectrum Analyz er HP3585A (input noi se of the HP3585A: 8nV/√Hz)
CC
=±2.5V
POWER SUPPLY BYPASSIN G
Correct power supply by pa ssing is very important for optimizing the performance in high frequency ranges. Bypass capacitors should be placed as close as pos sible to the IC pins t o improve high frequency bypassing. A capacitor greater than 1µF is necessary to minim ize the distortion. For a better quality bypassing a capac itor of 10nF can be added usin g the same implementation con di­tions. Bypass capacit ors mu st be incorporat ed f or both the negative and the positive supply.
Figure 63: Circuit for Power Supply Bypassing
The following figure shows the case of a 5V single power suppl y configuration
Figure 64: Circuit for +5V single supply
+5V
+5V
10µF
10µF
+
IN
IN
+5V
+5V
R1
R1 820
820
R2
R2
820
820
Rin
Rin 1k
1k
+ 1µF
+ 1µF
10nF
10nF
+
½ TS616
½ TS616
_
_
fb
fb
R
R
R
G
G
+
+
CG
CG
R
The TS616 operates with power supplies from 12V down to 5V. This can be achieved by either a
dual power sup plies of ±6V or ±2.5V or a single power supply of 12V or 5V referenced to the ground. In the case of asymmetrical supply, a new biasing is necessary to assume a positive output dynamic range between 0V and +V Considering the values of V
OH and VOL, the ampli-
fier will provide an output dynamic from +0.5V to
10.6V on 25Ω load for a 12V supply and from
0.45V to 3.8V on 10 load for a 5V supply.
100µF
100µF
OUT
OUT
supply rails.
CC
10
10
SINGLE POWER SUPPLY
22/27
The amplifier must be biased with a mid-supply (nominally +V
/2), in order to maintain the DC
CC
component of the signa l at this val ue. Several op­tions are possible to provide this bias supply, such as a virtual ground using an o perational amplifier or a two-resistance di vider (whi ch is the cheapest solution). A high resistance value is required to limit the current cons umption. O n the other hand, the current must be high enough to bias the non-inverting input of t he am plifier. If we consider
TS616
this bias current (30µA max.) as the 1% of the cur­rent through the resist ance divider to keep a sta­ble mid-supply, two resistances of 2.2kcan be used in the case of a 12V power supply and two resistances of 820can be u sed in the case of a 5V power supply. The input provides a high pass filter with a break frequency below 10Hz which is necessary to re­move the original 0 volt DC component of the input signal, and to fix it at +V
CC
/2.
CHANNEL SEPARATION - CROSSTALK
The following figure shows the crosstalk from an amplifier to a second amplifier. This phenomenon, accentuated at high frequencies, is unavoidable and intrinsic to the circuit.
Nevertheless, the PCB layout also has an effect on the crosstalk level. Capacitive coupling be­tween signal wires, distance between critical sig­nal nodes and power supply bypassing are the most significant fact o rs.
Figure 65: Crosstalk vs. Frequency
AV=+4, Rfb=620Ω, VCC=±6V, Vout=2Vp
-50
-60
-70
-80
-90
-100
CrossTal k (dB)
-110
-120
-130 10k 100k 1M 10M
Frequency (Hz)
CHOICE OF THE FEEDBACK CIRCUIT Table 1: Closed-Loop Gain - Feedback Compo-
nents
V
CC
±6
±2.5
(V)
Gain
+1 750 +2 680 +4 620 +8 510
-1 680
-2 680
-4 620
-8 510 +1 1.1k +2 1k +4 910 +8 680
-1 1k
-2 1k
-4 910
-8 680
Rfb (Ω)
INVERTING AMPLIFIER BIASING
In this case a resistance R is necessary to achieve good input biasing, see Figure 66. This resistance is calculated by assuming the neg­ative and positive input bias current. The aim is to compensate for the offset bias current which could affect the input offset voltage and the output DC component. Assuming Ib-, Ib+, R volt output, the resistance R comes: R = R
in, Rfb and a zero
in // Rfb .
Figure 66: Compensation of the Input Bias Current
fb
fb
R
R
Ib-
Ib-
Rin
Rin
Ib+
Ib+
_
_
+
+
TS616
TS616
Vcc+
Vcc+
Vcc-
Vcc-
Output
Output
Load
Load
R
R
23/27
TS616
ACTIVE FI LT ER I N G Figure 67 : Low-Pass Active Filtering. Sallen-Key
C1
C1
R
R
1 R2
1 R2
IN
IN
The resistors R
fb and RG give the gain of the f ilter
+
+
C2
C2
TS616
TS616
_
_
R
R
fb
fb
910
RG
RG
910
OUT
OUT
25
25
as a classical non-inverting am plification configu­ration :
R
AVg1
fb
--------- -+== R
g
Assume the following expression i s the response of the system:
preferable to use very stabl e resisto rs and c apac­itances values.
In the case of R1=R2:
R
2C2C
------------------------------------=
ζ
2C1C
fb
--------- -
1
R
g
2
INCREASING THE LINE LEVEL BY USING AN ACTIVE IMPEDANCE MATCHING
With passive matching, the output signal ampli­tude of the driver must be twice the amplitude on the load. To go beyond this limitation, active matching impedance can be used. W ith this t ech­nique, it is possible to keep good impedance matching with an amplitude on the load higher than half of the output driver amplitude. This c on­cept is shown in Figure 68 for a differential line.
Figure 68: TS616 as a differential line driver with an active impedance matching
Vout
T
j
ω
------------------­Vin
j
j
ω
ω
---------------------------------------------== 12
------ -
ζ
ω
g
j
ω
c
j
ω()
------------- -++ 2
ω
c
2
the cut-off frequency is not gai n-dependent a nd it becomes:
1
------------------------------------- -=
ω
c
R1R2C1C2
The damping factor becomes:
1
-- -
=
ζ
ω
()
cC1R1C1R2C2R1C1R1
2
g++
The higher the gain, the more sensitive the damp­ing factor is. When the gain is higher than 1 it is
100n
Vcc+
1k
Vi
100n
100n
10µ
1k
GND
Vi Vo
1/2 R1
1/2 R1
+
_
+
_
Vcc/2
Vcc+
Rs1
GND
R2
R3
R5
R4
Vcc+
GND
Vo°
Vo°
Rs2
µ
1
10n
Vo
1:n
Hybrid
&
RL
Transformer
100
24/27
TS616
Component Calculation
Let us consider the equivalent circuit for a sin­gle-ended configuration as shown in Figure 69.
Figure 69: Single ended equivalent circuit
+
+
+
Vi
Vi
½ R1
½ R1
+
_
_
_
_
R2
R2
R3
R3
Vo°
Vo°
Rs1
Rs1
-1
-1
-1
-1
Vo
Vo
½ RL
½ RL
Let us consider the unloaded system . Assumi ng the currents through R1, R2 and R3 are respect ively:
2Vi
Vi Vo°–
()
---------
---------------------------and
R1
° equals Vo without load, the gain in this
as Vo
R2
Vi Vo+
()
------------------------, R3
case becomes :
2R2
----------­R1
R2
1
------- ­R3
R2
------- -++ R3
G
Vo noload
()
--------------------------------­Vi
1
------------------------------------==
2R2
----------­R1
R2
------- -– R3
R2
------- -++ R3
Rs1Iout
----------------------- e q 3 1
R2
------- -– R3
,=
()

Vi 1
Vo

------------------------------------------------
1
By identification of both equations (eq2) and (eq3), the synthesized impedance is, with Rs1=Rs2=Rs:
Ro
Rs
----------------- e q 4
,=
()
R2
1
------- -– R3
Figure 70: Equivalent schematic. Ro is the synthesized impedance .
Iout
1/2RL
° required for a passive imped-
Vi.Gi
Unlike the level Vo ance, Vo us write Vo
° will be smaller than 2Vo in our case. Let
°=kVo with k the m at ching f actor vary -
Ro
ing between 1 and 2. Assum ing that the current through R3 is negligible, (eq4) becomes the fol­lowing :
Ro
kVoRL
----------------------------- -= RL 2R s1+
The gain, for the loaded system will be (eq1):
2R2
----------­R1
R2
1
------- -– R3
R2
------- -++ R3
,==
()
GL
Vo withload
()
-------------------------------------­Vi
1
1
-- -
------------------------------------ e q 1
2
As shown in Figure70, this system is an ideal gen­erator with a synthesized impedance as the inter­nal impedance of the system. From this, the out­put voltage becomes:
Vo ViG
()
RoIout
= eq2
()
,
()
with Ro the synthesized impedance and Iout the output current. On the other hand Vo can be ex­pressed as:
After choosing the k factor, Rs will equal to 1/2RL(k-1). A good impedance matching assume s:
1
Ro
-- -RL eq5
,=
()
2
(eq4) and (eq5) give :
R2
------- -1 R3
2Rs
----------- e q 6
,=
()
RL
By fixing an arbitrary value of R2, (eq6) becomes :
R3
R2
-------------------- -=
2Rs
1
-----------– RL
Finally, the values of R2 and R3 allow us to extract R1 from (eq1), and it becomes:
25/27
TS616
R1
----------------------------------------------------------- e q 7 21
2R2
R2

------- -– R3
GL 1

,=
()
R2
------- -– R3
with GL the required gain. Table 2 : Components Calculation for Impedance
Matching Implementa tion
GL (gain for the loaded system)
R1 2R2/[2(1-R2/R3)GL-1-R2/R3] R2 (=R4) Abritra ry fixed R3 (=R5) R2/(1-Rs/0.5RL)
Rs 0.5RL(k-1)
Load view ed by
each driv er
GL is fixed for the application requirements GL=Vo/Vi=0.5(1+2R2/R1+R2/R3)/(1-R2/R3)
kRL/2
26/27
PACKAGE MECHANICAL DATA 8 PINS - PLASTIC MICROPACKAGE (SO Exposed-Pad)
TS616
Dim.
Millimeters Inches
Min. Typ. Max. Min. Typ. Max.
A 1.350 1.750 0.053 0.069 A1 0.000 0.250 0.001 0.010 A2 1.100 1.650 0.043 0.065
B 0.330 0.510 0.013 0.020
C 0.190 0.250 0.007 0.010
D 4.800 5.000 0.189 0.197
D1 3.10 0.122
E 3.800 4.000 0.150 0.157 E1 2.41 0.095
e 1.270 0.050
H 5.800 6.200 0.228 0.244
h 0.250 0.500 0.010 0.020
L 0.400 1.270 0.016 0.050
k0d 8d0d 8d
ddd 0.100 0.004
Information furnished is bel ieved to be accurate and reliable. However, STMicroe lectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No li cense is granted by i mp lica tion or otherwise under a n y patent or patent rig hts of STMicroelectronics. Spec ific at ions mentioned in this publication ar e subject to change without notice. This publication supersedes and replaces all information previously supplied. S TMicroelectronics products are not authorized for use as critica l components in life suppo rt devices or systems without express written approval of STMicroelectronics.
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27/27
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