Datasheet CLC5602IN, CLC5602IMX, CLC5602IM Datasheet (NSC)

Page 1
Features
130mA output current
0.06%, 0.02° differential gain, phase
1.5mA/ch supply current
135MHz bandwidth (Av= +2)
15ns settling to 0.05%
300V/µs slew rate
Stable for capacitive loads up to 1000pf
Single 5V or ±5V supplies
Applications
Video line driver
ADSL/HDSL driver
Coaxial cable driver
UTP differential line driver
Transformer/coil driver
High capacitive load driver
Portable/battery-powered applications
Differential A/D driver
Typical Application
Differential Line Driver with Load Impedance Conversion
Pinout
DIP & SOIC
General Description
The National CLC5602 has a new output stage that delivers high output drive current (130mA), but consumes minimal quiescent supply current (1.5mA/ch) from a single 5V supply. Its current feedback architecture, fabricated in an advanced comple­mentary bipolar process, maintains consistent performance over a wide range of gains and signal levels, and has a linear-phase response up to one half of the -3dB frequency.
The CLC5602 offers 0.1dB gain flatness to 22MHz and differen­tial gain and phase errors of 0.06% and 0.02°. These features are ideal for professional and consumer video applications.
The CLC5602 offers superior dynamic performance with a 135MHz small-signal bandwidth, 300V/µs slew rate and 5.7ns rise/fall times (2V
step
). The combination of low quiescent power, high output current drive, and high-speed performance make the CLC5602 well suited for many battery-powered personal communication/computing systems.
The ability to drive low-impedance, highly capacitive loads, makes the CLC5602 ideal for single ended cable applications. It also drives low impedance loads with minimum distortion. The CLC5602 will drive a 100load with only -86/-85dBc second/third harmonic distortion (Av= +2, V
out
= 2Vpp, f = 1MHz).
With a 25load, and the same conditions, it produces only -86/
-72dBc second/third harmonic distortion. The CLC5602 can also be used for driving differential-input step-
up transformers for applications such as Asynchronous Digital Subscriber Lines (ADSL) or High-Bit-Rate Digital Subscriber Lines (HDSL).
When driving the input of high-resolution A/D converters, the CLC5602 provides excellent -87/-95dBc second/third harmonic distortion (Av= +2, V
out
= 2Vpp, f = 1MHz, RL= 1k) and fast
settling time.
CLC5602 Dual, High Output,Video Amplifier
N
June 1999
CLC5602
Dual, High Output, Video Amplifier
© 1999 National Semiconductor Corporation http://www.national.com
Printed in the U.S.A.
Maximum Output Voltage vs. R
10
9
)
8
pp
7 6 5 4 3
Output Voltage (V
2 1
10
VCC = ±5V
Vs = +5V
100
RL ()
L
1000
R
g2
V
V
in
+
CLC5602
R
t1
-
R
g1
d/2
1/2
R
f1
R
t2
R
-
1/2
CLC5602
+
f2
Vo1
V
1
V
non-inv
-V
inv
1
CC
-V
d/2
R
m/2
1:n
R
eq
R
m/2
Z
UTP
o
I
o
+
R
V
L
o
-
+V Vo2 V
inv
V
non-inv
CC
2
2
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PARAMETERS CONDITIONS TYP MIN/MAX RATINGS UNITS NOTES Ambient Temperature CLC5602IN/IM +25°C +25°C 0 to 70°C -40 to 85°C
FREQUENCY DOMAIN RESPONSE
-3dB bandwidth V
o
= 0.5V
pp
100 85 75 70 MHz
V
o
= 2.0V
pp
65 60 55 50 MHz
-
0.1dB bandwidth Vo= 0.5V
pp
22 20 17 15 MHz
gain peaking <200MHz, V
o
= 0.5V
pp
0 0.5 0.9 1.0 dB
gain rolloff <30MHz, V
o
= 0.5V
pp
0.1 0.3 0.4 0.5 dB
linear phase deviation <30MHz, V
o
= 0.5V
pp
0.3 0.5 0.6 0.6 deg
differential gain NTSC, R
L
= 150to -1V 0.04 %
differential phase NTSC, R
L
= 150to -1V 0.09 deg
TIME DOMAIN RESPONSE
rise and fall time 2V step 6.1 8.5 9.2 10.0 ns settling time to 0.05% 1V step 25 35 50 80 ns overshoot 2V step 10 20 22 22 % slew rate 2V step 220 190 165 150 V/µs
DISTORTION AND NOISE RESPONSE
2
nd
harmonic distortion 2Vpp, 1MHz -77 -74 -71 -71 dBc
2V
pp
, 1MHz; RL= 1k -80 -77 -75 -70 dBc
2V
pp
, 5MHz -63 -59 -57 -57 dBc
3
rd
harmonic distortion 2Vpp, 1MHz -85 -81 -78 -78 dBc
2V
pp
, 1MHz; RL= 1k -82 -79 -76 -76 dBc
2V
pp
, 5MHz -62 -57 -54 -54 dBc
equivalent input noise
voltage (e
ni
) >1MHz 3.4 4.4 4.9 4.9 nV/√Hz
non-inverting current (i
bn
) >1MHz 6.3 8.2 9.0 9.0 pA/Hz
inverting current (i
bi
) >1MHz 8.7 11.3 12.4 12.4 pA/Hz
crosstalk (input referred) 10MHz, 1V
pp
-72 dB
STATIC DC PERFORMANCE
input offset voltage 1 4 5 6 mV A
average drift 7 15 15 µV/˚C
input bias current (non-inverting) 5 12 15 16 µAA
average drift 25 60 60 nA/˚C
input bias current (inverting) 3 10 12 13 µAA
average drift 10 20 20 nA/˚C power supply rejection ratio DC 48 45 43 43 dB common-mode rejection ratio DC 49 47 45 45 dB supply current per channel R
L
= 1.5 1.7 1.8 1.8 mA A
MISCELLANEOUS PERFORMANCE
input resistance (non-inverting) 0.46 0.36 0.32 0.32 M input capacitance (non-inverting) 1.8 2.75 2.75 2.75 pF input voltage range, High 4.2 4.1 4.1 4.0 V input voltage range, Low 0.8 0.9 0.9 1.0 V output voltage range, High R
L
= 100 4.0 3.9 3.9 3.8 V
output voltage range, Low R
L
= 100 1.0 1.1 1.1 1.2 V
output voltage range, High R
L
= 4.1 4.0 4.0 3.9 V
output voltage range, Low R
L
= 0.9 1.0 1.0 1.1 V output current 100 80 65 40 mA B output resistance, closed loop DC 55 90 90 120 m
Min/max ratings are based on product characterization and simulation. Individual parameters are tested as noted. Outgoing quality levels are determined from tested parameters.
+5V Electrical Characteristics
(Av= +2, Rf= 750Ω,RL= 100Ω,Vs= +5V1,Vcm= VEE+ (Vs/2), RLtied to Vcm, unless specified)
Absolute Maximum Ratings
supply voltage (VCC- VEE)
+
14V output current (see note C) 140mA common-mode input voltage
VEEto
V
CC
maximum junction temperature +150°C storage temperature range -65°C to +150°C lead temperature (soldering 10 sec) +300°C ESD rating (human body model) 1000V
Notes
A) J-level:spec is 100% tested at +25°C. B)The short circuit current can exceed the maximum safe
output current.
1) V
s
= VCC- V
EE
Reliability Information
Transistor Count 98 MTBF (based on limited test data) 290Mhr
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PARAMETERS CONDITIONS TYP GUARANTEED MIN/MAX UNITS NOTES Ambient Temperature CLC5602IN/IM +25°C +25°C 0 to 70°C -40 to 85°C
FREQUENCY DOMAIN RESPONSE
-3dB bandwidth V
o
= 1.0V
pp
135 115 105 100 MHz
V
o
= 4.0V
pp
48 45 42 40 MHz
-
0.1dB bandwidth Vo= 1.0V
pp
20 18 15 12 MHz
gain peaking <200MHz, V
o
= 1.0V
pp
0 0.5 0.9 1.0 dB
gain rolloff <30MHz, V
o
= 1.0V
pp
0.1 0.3 0.4 0.5 dB
linear phase deviation <30MHz, V
o
= 1.0V
pp
0.15 0.3 0.4 0.4 deg
differential gain NTSC, R
L
=150 0.06 0.18 %
differential phase NTSC, R
L
=150 0.02 0.04 deg
TIME DOMAIN RESPONSE
rise and fall time 2V step 5.7 6.2 6.8 7.3 ns settling time to 0.05% 2V step 15 25 40 60 ns overshoot 2V step 18 20 22 22 % slew rate 2V step 300 225 190 175 V/µs
DISTORTION AND NOISE RESPONSE
2
nd
harmonic distortion 2Vpp, 1MHz -86 -82 -79 -79 dBc
2V
pp
, 1MHz; RL= 1k -87 -83 -80 -80 dBc
2V
pp
, 5MHz -70 -64 -61 -60 dBc
3
rd
harmonic distortion 2Vpp, 1MHz -85 -81 -78 -78 dBc
2V
pp
, 1MHz; RL= 1k -95 -90 -87 -87 dBc
2V
pp
, 5MHz -66 -64 -61 -60 dBc
equivalent input noise
voltage (e
ni
) >1MHz 3.4 4.4 4.9 4.9 nV/√Hz
non-inverting current (i
bn
) >1MHz 6.3 8.2 9.0 9.0 pA/Hz
inverting current (i
bi
) >1MHz 8.7 11.3 12.4 12.4 pA/Hz
crosstalk (input referred) 10MHz, 1V
pp
-72 dB
STATIC DC PERFORMANCE
input offset voltage 2 6 7 8 mV
average drift 8 µV/˚C
input bias current (non-inverting) 5 12 16 17 µA
average drift 40 nA/˚C
input bias current (inverting) 8 24 28 28 µA
average drift 20 45 45 nA/˚C power supply rejection ratio DC 48 45 43 43 dB common-mode rejection ratio DC 51 49 47 47 dB supply current (per channel) R
L
= 1.6 1.9 2.0 2.0 mA
MISCELLANEOUS PERFORMANCE
input resistance (non-inverting) 0.59 0.47 0.43 0.43 M input capacitance (non-inverting) 1.45 2.15 2.15 2.15 pF common-mode input range
±
4.2
±
4.1
±
4.1
±
4.0 V
output voltage range R
L
= 100
±
3.8
±
3.6
±
3.6
±
3.5 V
output voltage range R
L
=
±
4.0
±
3.8
±
3.8
±
3.7 V output current 130 100 80 50 mA B output resistance, closed loop DC 40 70 70 90 m
±5V Electrical Characteristics
(Av= +2, Rf= 750Ω,RL= 100Ω,VCC= ±5V, unless specified)
Notes
B)The short circuit current can exceed the maximum safe
output current.
Ordering Information
Model Temperature Range Description
CLC5602IN -40°C to +85°C 8-pin PDIP CLC5602IM -40°C to +85°C 8-pin SOIC CLC5602IMX -40°C to +85°C 8-pin SOIC tape & reel
Pac kage Thermal Resistance
Package
θθ
JC
θθ
JA
Plastic (IN) 65°C/W 130°C/W Surface Mount (IM) 50°C/W 145°C/W
Page 4
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+5V T ypical Performance
(Av= +2, Rf= 750Ω,RL= 100Ω,Vs= +5V1,Vcm= VEE+ (Vs/2), RLtied to Vcm, unless specified)
Non-Inverting Frequency Response
Vo = 0.5V
pp
Gain
Av = +1
Rf = 1.0k
Phase
Av = +5
Rf = 301
Av = +10
Normalized Magnitude (1dB/div)
1M
Rf = 200
10M
Frequency (Hz)
Frequency Response vs. V
Vo = 1V
Vo = 2V
o
Vo = 0.1V
pp
pp
Magnitude (1dB/div)
1M
10M
Frequency (Hz)
PSRR & CMRR
60
PSRR
50
CMRR
40
30
20
PSRR & CMRR (dB)
10
0
1k 10k 100M
100k 1M 10M
Frequency (Hz)
2nd & 3rd Harmonic Distortion, RL = 25
-20
-30
3rd, 10MHz
-40
-50
2nd, 10MHz
-60
-70
Distortion (dBc)
-80
3rd, 1MHz
2nd, 1MHz
-90 0 0.5 1 1.5 2 2.5
Output Amplitude (Vpp)
Large & Small Signal Pulse Response
Large Signal
Small Signal
Output Voltage (0.5V/div)
Time (10ns/div)
Av = +2
Rf = 649
100M
100M
pp
Phase (deg)
0
-90
-180
-270
-360
-450
Inverting Frequency Response
Vo = 0.5V
pp
Gain
Av = -2
Rf = 649
Phase
Av = -5
Rf = 649
Av = -10
Normalized Magnitude (1dB/div)
1M
Rf = 500
10M
Frequency (Hz)
Gain Flatness & Linear Phase
Gain
Phase
Magnitude (0.05dB/div)
0
10
20
Frequency (MHz)
Equivalent Input Noise
3.6
3.5
3.4
Inverting Current 8.7pA/Hz
Non-Inverting Current 7pA/Hz
Voltage 3.35nV/Hz
3.3
Noise Voltage (nV/Hz)
3.2 10k 100k 1M 10M
Frequency (Hz)
2nd & 3rd Harmonic Distortion, RL = 100
-40
-50
3rd, 10MHz
-60
-70
-80
Distortion (dBc)
-90
2nd, 10MHz
3rd, 1MHz
2nd, 1MHz
-100 0 0.5 1 1.5 2 2.5
Output Amplitude (Vpp)
Closed Loop Output Resistance
100
VCC = ±5V
10
1
0.1
Output Resistance (Ω)
0.01
10k 100k 1M 10M
Frequency (Hz)
Av = -1
Rf = 649
100M
100M
180 135 90 45 0
-45
0.5
0.4
0.3
0.2
0.1 0
-0.1
-0.2
-0.3
30
12.5
10
7.5
5
2.5
Phase (deg)
Frequency Response vs. R
Vo = 0.5V
pp
Gain
Phase
RL = 25
RL = 1k
L
Phase (deg)
RL = 100
0
-90
-180
Magnitude (1dB/div)
-270
-360
-450
1M
10M
100M
Frequency (Hz)
Open Loop Transimpedance Gain, Z(s)
140
120
Phase (deg)
100
80
Magnitude (dBΩ)
60
40
Phase
Gain
1k 10k 100k 1M 10M 100M
225
180
Phase (deg)
135
90
45
0
Frequency (Hz)
2nd & 3rd Harmonic Distortion
-30
Vo = 2V
Noise Current (pA/Hz)
-40
-50
pp
3rd
RL = 1k
-60
2nd
-70
RL = 1k
-80
Distortion (dBc)
-90
2nd
RL = 100
3rd
RL = 100
-100 1M
10M
Frequency (Hz)
2nd & 3rd Harmonic Distortion, RL = 1k
-50
-60
3rd, 10MHz
2nd, 10MHz
-70
-80
Distortion (dBc)
2nd, 1MHz
-90
-100
3rd, 1MHz
0 0.5 1 1.5 2 2.5
Output Amplitude (Vpp)
IBI, IBN, VIO vs. Temperature
-1.5 3
V
1.0 2
(mV)
0.5 1
IO
00
-0.5 -1
-1.0 -2
Offset Voltage V
-1.5
IO
I
BI
I
BN
I
BI
, I
BN
(µA)
-3
-60 -20 20 60 100 140
Temperature (°C)
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±5V T ypical Performance
(Av= +2, Rf= 750Ω,RL= 100Ω,VCC= ±5V, unless specified)
Frequency Response
Vo = 1.0V
pp
Gain
Av = +1
Rf = 1.0k
Phase
Av = +5
Rf = 301
Av = +10
Normalized Magnitude (1dB/div)
1M
Rf = 200
10M
Av = +2
Rf = 649
100M
Frequency (Hz)
Frequency Response vs. V
Vo = 5V
Vo = 0.1V
Vo = 2V
o
pp
Vo = 1V
pp
pp
Magnitude (1dB/div)
1M
10M
100M
Frequency (Hz)
Large Signal Pulse Response
Av = +2
Amplitude (0.5V/div)
Av = -2
Time (20ns/div)
2nd & 3rd Harmonic Distortion, RL = 25
-30
-40
3rd, 10MHz
-50
-60
-70
-80
Distortion (dBc)
-90
2nd, 10MHz
3rd, 1MHz
2nd, 1MHz
-100 012345
Output Amplitude (Vpp)
Short Term Settling Time
0.2
0.15
0.1
0.05
0
-0.05
(% Output Step)
o
-0.1
V
-0.15
-0.2 1 10 100 1000 10000
Time (ns)
Inverting Frequency Response
Phase (deg)
0
-45
-90
-135
-180
-225
Vo = 1.0V
pp
Gain
Av = -1
Rf = 649
Phase
Av = -5
Rf = 649
Av = -10
Normalized Magnitude (1dB/div)
1M
Rf = 500
10M
Av = -2
Rf = 649
100M
Phase (deg)
180 135 90 45 0
-45
Frequency (Hz)
Gain Flatness & Linear Phase
pp
Gain
0.4
0.3
Phase (deg)
Frequency Response vs. R
Vo = 1.0V
pp
Gain
RL = 100
Phase
Magnitude (1dB/div)
1M
RL = 25
10M
Frequency (Hz)
Small Signal Pulse Response
Av = +2
L
Phase (deg)
RL = 1k
0
-90
-180
-270
-360
-450
100M
0.2
0.1
Phase
Magnitude (0.1dB/div)
0
Amplitude (200mV/div)
Av = -2
-0.1
0
10 15 20 30
5
25
Time (10ns/div)
Frequency (MHz)
Differential Gain & Phase
0
-0.04
-0.08
-0.12
Gain (%)
Phase Pos Sync
Gain Neg Sync Gain Pos Sync
Phase Neg Sync
-0.16
-0.2 1234
Number of 150 Loads
2nd & 3rd Harmonic Distortion, RL = 100
-40
-50
3rd, 10MHz
-60
-70
-80
-90
Distortion (dBc)
-100
2nd, 10MHz
3rd, 1MHz
2nd, 1MHz
-110 0 0.5 1 1.5 2 2.5
Output Amplitude (Vpp)
Long Term Settling Time
0.2
0.15
0.1
0.05
0
-0.05
(% Output Step)
o
-0.1
V
-0.15
-0.2 1µ10µ100µ1m 100m
10m
Time (s)
0
-0.04
-0.08
-0.12
-0.16
-0.2
2nd & 3rd Harmonic Distortion vs. Frequency
-30
Vo = 2V
-40
-50
Phase (deg)
pp
2nd
RL = 100
-60
2nd
RL = 1k
-70
-80
Distortion Level (dBc)
-90
RL = 1k
3rd
RL = 100
3rd
-100 110
Frequency (MHz)
2nd & 3rd Harmonic Distortion, RL = 1k
-50
-60
3rd, 10MHz
2nd, 10MHz
-70
-80
-90
Distortion (dBc)
2nd, 1MHz
3rd, 1MHz
-100
-110 012345
Output Amplitude (Vpp)
IBI, IBN, VOS vs. Temperature
1.4 3
1.3 2
(mV)
1.2 1
OS
1.1 0
I
BI
V
OS
I
BI
, I
BN
(µA)
1-1
I
0.9 -2
Offset Voltage V
0.8
BN
-3
-60 -20 20 60 100 140
Temperature (°C)
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±5V Typical Channel Matching Performance
(Av= +2, Rf= 750Ω,RL= 100Ω,VCC= ±5V, unless specified)
CLC5602 OPERATION
The CLC5602 is a current feedback amplifier built in an advanced complementary bipolar process. The CLC5602 operates from a single 5V supply or dual ±5V supplies. Operating from a single supply, the CLC5602 has the following features:
Provides 100mA of output current while consuming 7.5mW of power
Offers low -80/-82dB 2nd and 3rd harmonic distortion
Provides BW > 60MHz and 1MHz distortion < -65dBc at Vo = 2.0V
pp
The CLC5602 performance is further enhanced in ±5V supply applications as indicated in the
±5V Electrical
Characteristics
table and
±5V Typical Performance
plots.
Current Feedback Amplifiers
Some of the key features of current feedback technology are:
Independence of AC bandwidth and voltage gain
Inherently stable at unity gain
Adjustable frequency response with feedbac k resistor
High slew rate
Fast settling
Current feedback operation can be described using a simple equation. The voltage gain for a non-inverting or inverting current feedback amplifier is approximated by Equation 1.
Equation 1
where:
Avis the closed loop DC voltage gain
Rfis the feedback resistor
Z(jω) is the CLC5602’s open loop transimpedance gain
is the loop gain
The denominator of Equation 1 is approximately equal to 1 at low frequencies. Near the -3dB corner frequency, the interaction between Rfand Z(jω) dominates the circuit performance. The value of the feedback resistor has a large affect on the circuits performance. Increasing R
f
has the following affects:
Decreases loop gain
Decreases bandwidth
Reduces gain peaking
Lowers pulse response overshoot
Affects frequency response phase linearity
Refer to the
Feedback Resistor Selection
section for
more details on selecting a feedback resistor value.
V V
A
1
R
Z(j )
o
in
v
f
=
+
ω
Zj
R
f
ω
()
CLC5602 DESIGN INFORMATION
Single Supply Operation (VCC= +5V, VEE= GND)
The specifications given in the
+5V Electrical Character-
istics
table for single supply operation are measured with a common mode voltage (Vcm) of 2.5V. Vcmis the volt­age around which the inputs are applied and the output voltages are specified.
Operating from a single +5V supply, the Common Mode Input Range (CMIR) of the CLC5602 is typically +0.8V to
+4.2V. The typical output range with RL=100is +1.0V to +4.0V.
For single supply DC coupled operation, keep input signal levels above 0.8V DC. For input signals that drop below 0.8V DC, AC coupling and level shifting the signal are recommended. The non-inverting and inverting configurations for both input conditions are illustrated in the following 2 sections.
Channel Matching
Channel 2
Magnitude (0.5dB/div)
1M 10M 100M
Channel 1
Frequency (Hz)
Input Referred Crosstalk
-20
Vo = 1V
-30
-40
-50
-60
-70
Magnitude (dB)
-80
-90
pp
1M
Frequency (Hz)
Pulse Crosstalk
Active Output
Channel
Inactive Output
Channel
Active Channel
Amplitude (0.2V/div)
10M 100M
Time (10ns/div)
Amplitude (20mV/div)
Inactive Channel
Page 7
DC Coupled Single Supply Operation
Figures 1 and 2 show the recommended non-inverting and inverting configurations for input signals that remain above 0.8V DC.
Figure 1: Non-Inverting Configuration
Figure 2: Inverting Configuration
AC Coupled Single Supply Operation
Figures 3 and 4 show possible non-inverting and invert­ing configurations for input signals that go below 0.8V DC. The input is AC coupled to prevent the need for level shifting the input signal at the source. The resistive voltage divider biases the non-inverting input to VCC÷2 = 2.5V (For VCC= +5V).
Figure 3: AC Coupled Non-Inverting Configuration
Figure 4: AC Coupled Inverting Configuration
Dual Supply Operation
The CLC5602 operates on dual supplies as well as single supplies. The non-inverting and inverting configu­rations are shown in Figures 5 and 6.
Figure 5: Dual Supply Non-Inverting Configuration
Figure 6: Dual Supply Inverting Configuration
7 http://www.national.com
V
3
2
R
g
CC
8
+
1/2
CLC5602
-
4
6.8µF
+
0.1µF
1
R
f
V
o
A1
==+
V
in
V
o
R
L
V
cm
R
f
v
R
g
Note: Rt, RL and Rg are tied to Vcm for minimum power consumption and maximum output swing.
V
in
R
t
V
cm
V
cm
V
A
3
CLC5602
2
v
CC
6.8µF
+
0.1µF
8
+
+
1/2
-
-
4
R
R
Select Rt to yield
f
desired Rin = Rt || R
R
g
1
f
V
o
R
L
V
cm
g
Note: Rb, provides DC bias for non-inverting input.
Rb, RL and Rt are tied to Vcm for minimum power consumption and maximum output swing.
R
b
V
cm
R
cm
g
R
t
V
o
V
in
V
in
V
==
V
CC
6.8µF
+
V
CC
2
C
c
V
in
R
R
0.1µF
8
3
+
1/2
g
CLC5602
2
-
1
4
R
f
V
o
R
R
VV
=−
o
low frequencycutoff
f
2.5
+
in
R
g
=
2RC
1
π
gc
V
CC
6.8µF
+
0.1µF
V
in
R
t
3
2
R
g
8
+
1/2
CLC5602
-
4
V
EE
1
R
f
0.1µF
6.8µF
V
o
V
o
==+
A1
V
in
+
R
v
f
R
g
V
CC
6.8µF
+
R
c
R
3
2
R
g
8
+
1/2
CLC5602
-
4
0.1µF
1
R
f
V
o
C
1
π
c
in
,where: R
==
2RC
R
RR
>>
in
2
source
V
in
R
VV1
=+
o
f
in
+
R
g
low frequencycutoff
V
C
CC
2
2.5
V
CC
6.8µF
+
8
+
1/2
CLC5602
-
4
V
EE
0.1µF
1
R
f
0.1µF
6.8µF
Note: Rb provides DC bias for the non-inverting input.
Select R Rin = Rt || Rg.
+
V
o
to yield desired
t
V
in
R
t
V
o
A
==
V
in
R
b
3
2
R
g
R
v
f
R
g
Page 8
http://www.national.com 8
Feedback Resistor Selection
The feedback resistor, Rf, affects the loop gain and frequency response of a current feedback amplifier. Optimum performance of the CLC5602, at a gain of +2V/V, is achieved with Rfequal to 750.The frequency response plots in the
Typical Performance
sections illustrate the recommended Rffor several gains. These recommended values of Rfprovide the maximum band­width with minimal peaking. Within limits, Rfcan be adjusted to optimize the frequency response.
Decrease Rfto peak frequency response and extend bandwidth
Increase Rfto roll off frequency response and compress bandwidth
As a rule of thumb, if the recommended Rfis doubled, then the bandwidth will be cut in half.
Unity Gain Operation
The recommended Rffor unity gain (+1V/V) operation is 1kΩ.Rgis left open. Parasitic capacitance at the inverting node may require a slight increase in Rfto maintain a flat frequency response.
Load Termination
The CLC5602 can source and sink near equal amounts of current. For optimum performance, the load should be tied to Vcm.
Driving Cables and Capacitive Loads
When driving cables, double termination is used to prevent reflections. For capacitive load applications, a small series resistor at the output of the CLC5602 will improve stability and settling performance. The
Frequency Response vs. C
L
plot, shown below in Figure 7, gives the recommended series resistance value for optimum flatness at various capacitive loads.
Figure 7: Frequency Response vs. C
L
Transmission Line Matching
One method for matching the characteristic impedance (Zo) of a transmission line or cable is to place the appropriate resistor at the input or output of the amplifier.
Figure 8 shows typical inverting and non-inverting circuit configurations for matching transmission lines.
Non-inverting gain applications:
Connect Rgdirectly to ground.
Make R1, R2, R6, and R7equal to Zo.
Use R3to isolate the amplifier from reactive loading caused by the transmission line, or by parasitics.
Figure 8:Transmission Line Matching
Inverting gain applications:
Connect R3directly to ground.
Make the resistors R4, R6, and R7equal to Zo.
Make R5II Rg= Zo.
The input and output matching resistors attenuate the signal by a factor of 2, therefore additional gain is needed. Use C6to match the output transmission line over a greater frequency range. C6compensates for the increase of the amplifier’s output impedance with frequency.
Power Dissipation
Follow these steps to determine the power consumption of the CLC5602:
1. Calculate the quiescent (no-load) power: P
amp
= ICC(VCC- VEE)
2. Calculate the RMS power at the output stage: Po= (VCC- V
load
) (I
load
), where V
load
and I
load
are the RMS voltage and current across the external load.
3. Calculate the total RMS power: Pt= P
amp
+ P
o
The maximum power that the DIP and SOIC packages can dissipate at a given temperature is illustrated in Figure 9. The power derating curve for any CLC5602 package can be derived by utilizing the following equation:
where T
amb
= Ambient temperature (°C)
θJA= Thermal resistance, from junction to ambient,
for a given package (°C/W)
Vo = 1V
pp
CL = 10pF
Rs = 46.4
CL = 100pF
Rs = 20
CL = 1000pF
Rs = 6.7
+
R
-
Magnitude (1dB/div)
1k
1M
s
C
1k
Frequency (Hz)
1k
L
10M
100M
C
Z
R
1
+
V
1
­R
4
+
V
2
-
0
Z
0
R
3
+
1/2
CLC5602
R
2
-
R
R
5
R
g
f
6
Z
0
R
6
V
o
R
7
(175 T
°− )
amb
θ
JA
Page 9
9 http://www.national.com
Figure 9: Power Derating Curves
Layout Considerations
A proper printed circuit layout is essential for achieving high frequency performance. National provides evaluation boards for the CLC5602 (CLC730038-DIP, CLC730036-SOIC) and suggests their use as a guide for high frequency layout and as an aid f or de vice testing and characterization.
General layout and supply bypassing play major roles in high frequency performance. Follow the steps below as a basis for high frequency layout:
Include 6.8µF tantalum and 0.1µF ceramic capacitors on both supplies.
Place the 6.8µF capacitors within 0.75 inches of the power pins.
Place the 0.1µF capacitors less than 0.1 inches from the power pins.
Remove the ground plane under and around the part, especially near the input and output pins to reduce parasitic capacitance.
Minimize all trace lengths to reduce series inductances.
Use flush-mount printed circuit board pins for prototyping, never use high profile DIP sockets.
Evaluation Board Information
A data sheet is available f or the CLC730038/ CLC730036 evaluation boards. The evaluation board data sheet provides:
Evaluation board schematics
Evaluation board lay outs
General information about the boards
The evaluation boards are designed to accommodate dual supplies. The boards can be modified to provide single supply operation. For best performance; 1) do not connect the unused supply, 2) ground the unused supply pin.
SPICE Models
SPICE models provide a means to evaluate amplifier designs. Free SPICE models are available for National’s monolithic amplifiers that:
Support Berkeley SPICE 2G and its many derivatives
Reproduce typical DC, AC, Transient, and Noise performance
Support room temperature simulations
The
readme
file that accompanies the diskette lists released models, and provides a list of modeled parame­ters. The application note OA-18, Simulation SPICE Models for National’s Op Amps, contains schematics and a reproduction of the readme file.
Single Supply Cable Driver
The typical application shown below shows one of the CLC5602 amplifiers driving 10m of 75coaxial cable. The CLC5602 is set for a gain of +2V/V to compensate for the divide-by-two voltage drop at Vo.
Figure 10: Single Supply Cable Driver
Figure 11: Response After 10m of Cable
Single Supply Lowpass Filter
Figures 12 and 13 illustrate a lowpass filter and design equations. The circuit operates from a single supply of +5V. The voltage divider biases the non-inverting input to
2.5V. And the input is AC coupled to prevent the need f or level shifting the input signal at the source. Use the design equations to determine R1, R2, C1, and C2based on the desired Q and corner frequency.
Application Circuits
1.0
0.8
0.6
IN
IM
0.4
Power (W)
0.2
0
-40 -20 0 20 40 60 80 100 120 180
Ambient Temperature (°C)
140 160
+5V
6.8µF
+
5k
0.1µF
5k
3
2
1k
8
+
1/2
CLC5602
-
4
0.1µF
1k
1
0.1µF
75
10m of 75
Coaxial Cable
Vin = 10MHz, 0.5V
pp
75
0.1µF
V
in
V
o
100mV/div
20ns/div
Page 10
http://www.national.com 10
Figure 12: Lowpass Filter Topology
Figure 13: Design Equations
This example illustrates a lowpass filter with Q = 0.707 and corner frequency fc= 10MHz. A Q of 0.707 was chosen to achieve a maximally flat, Butterworth response. Figure 14 indicates the filter response.
Figure 14: Lowpass Response
Differential Line Driver With Load Impedance Conversion
The circuit shown in the
Typical Application
schematic on the front page and in Figure 15, operates as a differential line driver. The transformer converts the load impedance to a value that best matches the CLC5602’s output capabilites. The single-ended input signal is converted to a differential signal by the CLC5602. The line’s characteristic impedance is matched at both the input and the output. The schematic shows Unshielded Twisted Pair for the transmission line;other types of lines can also be driven.
Figure 15: Differential Line Driver wtih
Load Impedance Conversion
Set up the CLC5602 as a difference amplifier:
Make the best use of the CLC5602’s output drive capability as follows:
where Reqis the transformed value of the load imped­ance, V
max
is the Output Voltage Range, and I
max
is the
maximum Output Current. Match the line’s characteristic impedance:
Select the transformer so that it loads the line with a value very near Zoover frequency range. The output impedance of the CLC5602 also affects the match. With an ideal transformer we obtain:
+5V
8
+
1/2
CLC5602
-
4
0.1µF C
1
1
R
f
1k
0.1µF
100
0.1µF
V
in
5k
R
1
158 5k
R
2
158
100pF
1.698k
3
C
2
2
R
g
0.1µF
V
o
R
Gain K 1
==+
Corner frequency
Q
=
RC
22
RC
11
For R R R and C C C
ω
Q
== ==
12 12
1
=
c
RC
1
=
(3 K)
f
R
g
ω
==
c
1
RR CC
1212
1
RC
12
++
RC
21
(1 K)
RC
11
RC
22
R
g2
V
+
1/2
CLC5602
-
d/2
R
f1
V
in
R
t1
R
g1
R
f2
R
-
1/2
CLC5602
+
R
t2
m/2
-V
d/2
1:n
R
eq
R
m/2
Z
UTP
I
o
o
R
L
V
d
21
=⋅+
V
in
 
R
f1
R
g1
=⋅
 
R
f2
2
R
g2
2V
RR
+=
meq
I
max
max
+
V
o
-
3
-3
-9
Magnitude (dB)
-15
-21 1M 10M 100M
Frequency (Hz)
RZ
=
Lo
RR
=
meq
R
n
L
=
R
eq
2
nZ j
ReturnLoss 20 log
=− ⋅
10
o 5602
()
Z
o
ω
()
,dB
Page 11
11 http://www.national.com
where Z
o(5602)
(jω) is the output impedance of the
CLC5602 and |Z
o(5602)
(jω)| << Rm.
The load voltage and current will fall in the ranges:
The CLC5602’s high output drive current and low distortion make it a good choice for this application.
Full Duplex Cable Driver
The circuit shown in Figure 16 below, operates as a full duplex cable driver which allows simultaneous transmis­sion and reception of signals on one transmission line. The circuit on either side of the transmission line uses are CLC5602 as a cable driver, and the second CLC5602 as a receiver. VoAis an attenuated version of VinA, while V
oB
is an attenuated version of V
inB
.
Figure 16: Full Duplex Cable Driver
Rm1is used to match the transmission line. Rf2and R
g2
set the DC gain of the CLC5602, which is used in a difference mode. Rt2provides good CMRR and DC offset. The transmitting CLC5602’s are shown in a unity gain configuration because they consume the least power of any gain, for a given load. For proper operation we need Rf2= Rg2.
The receiver output voltages are:
where A is the attenuation of the cable, Z
o(5602)
(jω) is the
output impedance of the CLC5602 (see the
Closed-Loop
Output Resistance
plot), and |Z
o(5602)
(jω)| << Rm1.
We selected the component values as follows:
Rf1= 1.0k, the recommended value for the CLC5602 at unity gain
Rm1= Zo= 50, the characteristic impedance of the transmission line
Rf2= Rg2= 750≥ Rm1, the recommended value for the CLC5602 at Av = 2
These values give excellent isolation from the other input:
The CLC5602 provides large output current drive, while consuming little supply current, at the nominal bias point. It also produces low distortion with large signal swings and heavy loads. These features make the CLC5602 an excellent choice for driving transmission lines.
VnV
≤⋅
o
I
o
I
max
max
n
V
inA
R
t1
V
oB
+
1/2
CLC5602
-
R
f1
R
f2
1/2
CLC5602
R
m1
R
g2
-
R
t2
+
Z
0
R
m1
R
R
t2
CLC5602
g2
1/2
R
f1
R
f2
-
1/2
CLC5602
+
+
-
V
inB
R
t1
V
oA
inB(A)
2
R
f2
1
R
g2
VVA
outA(B) inA(B)
≈⋅+⋅−+
V
Z(j)
o(5602)
R
ω
 
m1
R
R(R||R)
==
t2
g2
f2
m1
2
25
V
oA(B)
V
inB(A)
38dB, f 5.0MHz
≈− =
Page 12
CLC5602
Dual, High Output, Video Amplifier
http://www.national.com 12
Customer Design Applications Support
National Semiconductor is committed to design excellence. For sales, literature and technical support, call the National Semiconductor Customer Response Group at 1-800-272-9959 or fax 1-800-737-7018.
Life Support Policy
National’s products are not authorized for use as critical components in life support devices or systems without the express written approval of the president of National Semiconductor Corporation. As used herein:
1. Life support devices or systems are devices or systems which, a) are intended for surgical implant into the body, or b) support or
sustain life, and whose failure to perfor m, when proper ly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user.
2. A cr itical component is any component of a life support device or system whose failure to perform can be reasonably expected to
cause the failure of the life support device or system, or to affect its safety or effectiveness.
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1111 West Bardin Road Fax: (+49) 0-180-530 85 86 2501 Miramar Tower Tel: 81-043-299-2309 Arlington, TX 76017 E-mail: europe.support.nsc.com 1-23 Kimberley Road Fax: 81-043-299-2408 Tel: 1(800) 272-9959 Deutsch Tel: (+49) 0-180-530 85 85 Tsimshatsui, Kowloon Fax:1(800) 737-7018 English Tel:(+49) 0-180-532 78 32 Hong Kong
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National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.
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