Datasheet EL5420CL-T13, EL5420CL, EL5420CS-T7, EL5420CS-T13, EL5420CS Datasheet (ELANT)
...Page 1
EL5220C, EL5420C
12MHz Rail-to-Rail Input-Output Op Amps
EL5220C, EL5420C
Features
• 12MHz -3dB bandwidth
• Supply voltage = 4.5V to 16.5V
• Low supply current (per amplifier)
= 500µA
• High slew rate = 10V/µs
• Unity-gain stable
• Beyond the rails input capability
• Rail-to-rail output swing
• Ultra-small package
Applications
• TFT-LCD drive circuits
• Electronics notebooks
• Electronics games
• Touch-screen displays
• Personal communication devices
• Personal digital assistants (PDA)
• Portable instrumentation
• Sampling ADC amplifiers
• Wireless LANs
• Office automation
• Active filters
• ADC/DAC buffer
General Description
The EL5420C and EL5220C are low power, high voltage, rail-to-rail
input-output amplifiers. The EL5220C contains two amplifiers in one
package, and the EL5420C contains four amplifiers. Operating on supplies ranging from 5V to 15V, while consuming only 500µA per
amplifier, the EL5420C and EL5220C have a bandwidth of 12MHz --
(-3dB). They also provide common mode input ability beyond the supply rails, as well as rail-to-rail output capability. This enables these
amplifiers to offer maximum dynamic range at any supply voltage.
The EL5420C and EL5220C also feature fast slewing and settling
times, as well as a high output drive capability of 30mA (sink and
source). These features make these amplifiers ideal for use as voltage
reference buffers in Thin Film Transistor Liquid Crystal Displays
(TFT-LCD). Other applications include battery power, portable
devices, and anywhere low power consumption is important.
The EL5420C is available in a space-saving 14-pin TSSOP package,
the industry-standard 14-pin SO package, as well as a 16-pin LPP
package. The EL5220C is available in the 8-pin MSOP package. Both
feature a standard operational amplifier pin out. These amplifiers are
specified for operation over the full -40°C to +85°C temperature
range.
Connection Diagrams
1
VOUTA
Ordering Information
Part No. Package
EL5220CY 8-Pin MSOP - MDP0043
EL5220CY-T7 8-Pin MSOP 7” MDP0043
EL5220CY-T13 8-Pin MSOP 13” MDP0043
EL5420CL 16-Pin LPP - MDP0046
EL5420CL-T7 16-Pin LPP 7” MDP0046
EL5420CL-T13 16-Pin LPP 13” MDP0046
EL5420CR 14-Pin TSSOP - MDP0044
EL5420CR-T7 14-Pin TSSOP 7” MDP0044
EL5420CR-T13 14-Pin TSSOP 13” MDP0044
EL5420CS 14-Pin SO - MDP0027
EL5420CS-T7 14-Pin SO 7” MDP0027
EL5420CS-T13 14-Pin SO 13” MDP0027
Note: All information contained in this data sheet has been carefully checked and is believed to be accurate as of the date of publication; however, this data sheet cannot be a “controlled document”. Current revisions, if any, to these
specifications are maintained at the factory and are available upon your request. We recommend checking the revision level before finalization of your design documentation.
© 2001 Elantec Semiconductor, Inc.
Tape &
Reel Outline #
2
VINA-
VINA+
VINB+
VINB-
VOUTB
Connection Diagrams are continued on page 4
-
3
+
4
5
+
6
-
7
EL5420C
(14-Pin TSSOP & 14-Pin SO)
14
VOUTD
13
VIND-
12
+
VIND+
1
11
VS-VS+
10
VINC+
+
9
-
VINC-
8
VOUTC
VOUTA
VINA-
VINA+
VS-
2
3
4
+
EL5220C
(8-Pin MSOP)
8
VS+
7
VOUTB
65-
VINB-
+
VINB+
September 19, 2001
Page 2
EL5220C, EL5420C
12MHz Rail-to-Rail Input-Output Op Amps
Absolute Maximum Ratings (T
Values beyond absolute maximum ratings can cause the device to be prematurely damaged. Absolute maximum ratings are stress ratings only
EL5220C, EL5420C
and functional device operation is not implied
Supply Voltage between VS+ and VS- +18V
Input Voltage VS- - 0.5V, VS +0.5V
Maximum Continuous Output Current 30mA
= 25°C)
A
Maximum Die Temperature +125°C
Storage Temperature -65°C to +150°C
Operating Temperature -40°C to +85°C
Power Dissipation See Curves
ESD Voltage 2kV
Important Note:
All parameters having Min/Max specifications are guaranteed. Typ values are for information purposes only. Unless otherwise noted, all tests are at the
specified temperature and are pulsed tests, therefore: TJ = TC = T
A
Electrical Characteristics
VS+= +5V, VS - = -5V, R
Parameter Description Condition Min Typ Max Unit
Input Characteristics
V
OS
TCV
OS
I
B
R
IN
C
IN
CMIR Common-Mode Input Range -5.5 +5.5 V
CMRR Common-Mode Rejection Ratio for VIN from -5.5V to +5.5V 50 70 dB
A
VOL
Output Characteristics
V
OL
V
OH
I
SC
I
OUT
Power Supply Performance
PSRR Power Supply Rejection Ratio VS is moved from ±2.25V to ±7.75V 60 80 dB
I
S
Dynamic Performance
SR Slew Rate
t
S
BW -3dB Bandwidth R
GBWP Gain-Bandwidth Product R
PM Phase Margin R
CS Channel Separation f = 5MHz 75 dB
1. Measured over operating temperature range
2. Slew rate is measured on rising and falling edges
= 10kΩ and C
L
Input Offset Voltage V
Average Offset Voltage Drift
Input Bias Current V
= 10pF to 0V, TA = 25°C unless otherwise specified.
L
= 0V 2 12 mV
CM
[1]
= 0V 2 50 nA
CM
5 µV/°C
Input Impedance 1 GΩ
Input Capacitance 1.35 pF
Open-Loop Gain -4.5V ≤ V
≤ +4.5V 75 95 dB
OUT
Output Swing Low IL = -5mA -4.92 -4.85 V
Output Swing High IL = 5mA 4.85 4.92 V
Short Circuit Current ±120 mA
Output Current ±30 mA
Supply Current (Per Amplifier) No load 500 750 µA
[2]
-4.0V ≤ V
≤ +4.0V, 20% to 80% 10 V/µs
OUT
Settling to +0.1% (AV = +1) (AV = +1), VO = 2V step 500 ns
= 10kΩ, C
L
= 10kΩ, C
L
= 10kΩ, C
L
= 10pF 12 MHz
L
= 10pF 8 MHz
L
= 10 pF 50 °
L
2
Page 3
EL5220C, EL5420C
12MHz Rail-to-Rail Input-Output Op Amps
Electrical Characteristics
VS+ = 5V, VS-= 0V, R
Parameter Description Condition Min Typ Max Unit
Input Characteristics
V
OS
TCV
OS
I
B
R
IN
C
IN
CMIR Common-Mode Input Range -0.5 +5.5 V
CMRR Common-Mode Rejection Ratio for VIN from -0.5V to +5.5V 45 66 dB
A
VOL
Output Characteristics
V
OL
V
OH
I
SC
I
OUT
Power Supply Performance
PSRR Power Supply Rejection Ratio VS is moved from 4.5V to 15.5V 60 80 dB
I
S
Dynamic Performance
SR Slew Rate
t
S
BW -3dB Bandwidth R
GBWP Gain-Bandwidth Product R
PM Phase Margin R
CS Channel Separation f = 5MHz 75 dB
1. Measured over operating temperature range
2. Slew rate is measured on rising and falling edges
= 10kΩ and C
L
Input Offset Voltage V
Average Offset Voltage Drift
Input Bias Current V
= 10pF to 2.5V, TA = 25°C unless otherwise specified.
L
= 2.5V 2 10 mV
CM
[1]
= 2.5V 2 50 nA
CM
5 µV/°C
Input Impedance 1 GΩ
Input Capacitance 1.35 pF
Open-Loop Gain 0.5V ≤ V
≤+ 4.5V 75 95 dB
OUT
Output Swing Low IL = -5mA 80 150 mV
Output Swing High IL = +5mA 4.85 4.92 V
Short Circuit Current ±120 mA
Output Current ±30 mA
Supply Current (Per Amplifier) No load 500 750 µA
[2]
1V ≤ V
≤ 4V, 20% to 80% 10 V/µs
OUT
Settling to +0.1% (AV = +1) (AV = +1), VO = 2V step 500 ns
= 10kΩ, C
L
= 10 kΩ, C
L
= 10 kΩ, C
L
= 10pF 12 MHz
L
= 10pF 8 MHz
L
= 10 pF 50 °
L
EL5220C, EL5420C
Electrical Characteristics
VS+ = 15V, VS- = 0V, R
Parameter Description Condition Min Typ Max Unit
Input Characteristics
V
OS
TCV
OS
I
B
R
IN
C
IN
CMIR Common-Mode Input Range -0.5 +15.5 V
CMRR Common-Mode Rejection Ratio for VIN from -0.5V to +15.5V 53 72 dB
A
VOL
Output Characteristics
V
OL
V
OH
= 10kΩ and C
L
Input Offset Voltage V
Average Offset Voltage Drift
Input Bias Current V
= 10pF to 7.5V, TA = 25°C unless otherwise specified.
L
= 7.5V 2 14 mV
CM
[1]
= 7.5V 2 50 nA
CM
5 µV/°C
Input Impedance 1 GΩ
Input Capacitance 1.35 pF
Open-Loop Gain 0.5V ≤ V
≤ 14.5V 75 95 dB
OUT
Output Swing Low IL = -5mA 80 150 mV
Output Swing High IL = +5mA 14.85 14.92 V
3
Page 4
EL5220C, EL5420C
12MHz Rail-to-Rail Input-Output Op Amps
Electrical Characteristics (Continued)
VS+ = 15V, VS- = 0V, R
Parameter Description Condition Min Typ Max Unit
EL5220C, EL5420C
I
SC
I
OUT
Power Supply Performance
PSRR Power Supply Rejection Ratio VS is moved from 4.5V to 15.5V 60 80 dB
I
S
Dynamic Performance
SR Slew Rate
t
S
BW -3dB Bandwidth R
GBWP Gain-Bandwidth Product R
PM Phase Margin R
CS Channel Separation f = 5MHz 75 dB
1. Measured over operating temperature range
2. Slew rate is measured on rising and falling edges
Connection Diagrams (Continued)
= 10kΩ and C
L
= 10pF to 7.5V, TA = 25°C unless otherwise specified.
L
Short Circuit Current ±120 mA
Output Current ±30 mA
Supply Current (Per Amplifier) No load 500 750 µA
[2]
1V ≤ V
≤ 14V, 20% to 80% 10 V/µs
OUT
Settling to +0.1% (AV = +1) (AV = +1), VO = 2V step 500 ns
= 10kΩ, C
L
= 10kΩ, C
L
= 10kΩ, C
L
= 10pF 12 MHz
L
= 10pF 8 MHz
L
= 10 pF 50 °
L
VINA-
VINA+
VS+
VINB+
NC
VOUTA
VOUTD
16
15
1
2
Thermal Pad
3
4
5
6
VINB-
VOUTB
EL5420C
(16-Pin LPP)
NC
14
13
12
VIND-
11
VIND+
10
VS-
9
VINC+
7
8
VINC-
VOUTC
4
Page 5
Typical Performance Curves
EL5220C, EL5420C
EL5220C, EL5420C
12MHz Rail-to-Rail Input-Output Op Amps
EL5420C Input Offset Voltage Distribution
1800
VS=±5V
1600
TA=25°C
1400
1200
1000
800
600
Quantity (Amplifiers)
400
200
0
10
5
0
Input Offset Voltage (mV)
-5
-8-6-4-2-0
-12
-10
Input Offset Voltage (mV)
Input Offset Voltage vs Temperature
0 150
Temperature (°C)
246
50-50 100
Typical
Production
Distribution
8
10
VS=±5V
EL5420C Input Offset Voltage Drift
70
VS=±5V
60
50
40
30
Quantity (Amplifiers)
20
10
0
1
3
5
7
9
12
2.0
0.0
Input Bias Current (nA)
-2.0
Input Offset Voltage Drift, TCVOS (µV/°C)
Input Bias Current vs Temperature
VS=±5V
0 15050-50 100
11
Temperature (°C)
Typical
Production
Distribution
13
15
17
19
21
Output High Voltage vs Temperature
4.97
4.96
4.95
Output High Voltage (V)
4.94
4.93
0 150
50-50 100
Temperature (°C)
VS=±5V
I
OUT
=5mA
Output Low Voltage vs Temperature
-4.91
-4.92
-4.93
-4.94
-4.95
Output Low Voltage (V)
-4.96
-4.97
VS=±5V
I
=-5mA
OUT
0 150
50-50 100
Temperature (°C)
5
Page 6
EL5220C, EL5420C
12MHz Rail-to-Rail Input-Output Op Amps
Typical Performance Curves
EL5220C, EL5420C
Open-Loop Gain vs Temperature
100
90
Open-Loop Gain (dB)
80
0 150
50-50 100
Temperature (°C)
EL5420C Supply Current per Amplifier vs Temperature
0.55
0.5
Supply Current (mA)
0.45
0 150
50-50 100
Temperature (°C)
VS=±5V
RL=10kΩ
VS=±5V
Slew Rate vs Temperature
10.40
10.35
10.30
Slew Rate (V/µS)
10.25
0 150
EL5420C Supply Current per Amplifier vs Supply Voltage
700
TA=25°C
600
500
Supply Current (µA)
400
300
5 20
50-50 100
Temperature (°C)
100
Supply Voltage (V)
VS=±5V
15
Open Loop Gain and Phase vs Frequency
200
150
100
Gain (dB)
50
VS=±5V, TA=25°C
RL=10KΩ to GND
0
CL=12pF to GND
-50
10 10k 100M
100 1k 100k 1M 10M
Phase
Gain
Frequency (Hz)
20
-30
-80
-130
-180
-230
Frequency Response for Various R
5
0
CL=10pF
-5
Phase(°)
AV=1
VS=±5V
-10
Magnitude (Normalized) (dB)
-15
100k
1M
Frequency (Hz)
L
10kΩ
1kΩ
560Ω
150Ω
10M
100M
6
Page 7
Typical Performance Curves
EL5220C, EL5420C
EL5220C, EL5420C
12MHz Rail-to-Rail Input-Output Op Amps
Frequency Response for Various C
20
RL=10kΩ
10
AV=1
VS=±5V
0
-10
-20
Magnitude (Normalized) (dB)
-30
100k
Maximum Output Swing vs Frequency
12
)
10
P-P
8
6
VS=±5V
TA=25°C
4
AV=1
RL=10kΩ
Maximum Output Swing (V
2
CL=12pF
Distortion <1%
0
10k 100
1000pF
1M
Frequency (Hz)
Frequency (Hz)
L
12pF
50pF
100pF
10M
1M
100M
10M
Closed Loop Output Impedance vs Frequency
200
AV=1
160
VS=±5V
TA=25°C
120
80
Output Impedance (Ω)
40
0
10k 100
CMRR vs Frequency
80
60
40
CMRR (dB)
20
VS=±5V
TA=25°C
0
100
Frequency (Hz)
1k
10k
Frequency (Hz)
100k
1M
10M
1M
10M
80
60
40
PSRR (dB)
20
0
100
PSRR vs Frequency
PSRR+
PSRR-
VS=±5V
TA=25°C
1k
10k
Frequency (Hz)
100k
Input Voltage Noise Spectral Density vs Frequency
600
100
10
Voltage Noise (nV√Hz)
1
1M
10M
100 100k 100M
Frequency (Hz)
10M1k 10k 1M
7
Page 8
EL5220C, EL5420C
12MHz Rail-to-Rail Input-Output Op Amps
Typical Performance Curves
EL5220C, EL5420C
Total Harmonic Distortion + Noise vs Frequency
0.010
0.009
0.008
0.007
0.006
0.005
THD+ N (%)
0.004
VS=±5V
RL=10kΩ
0.003
AV=1
0.002
VIN=1V
RMS
1k 10k 100k
Small-Signal Overshoot vs Load Capacitance
VS=±5V
AV=1
RL=10kΩ
VIN=±50mV
TA=25°C
Frequency (Hz)
Overshoot (%)
0.001
90
70
50
30
10
Channel Separation vs Frequency Response
-60
Dual measured Channel A to B
Quad measured Channel A to D or B to C
Other combinations yield improved rejection
-80
VS=±5V
RL=10kΩ
AV=1
VIN=220mV
-100
X-Talk (dB)
-120
-140
1k
Settling Time vs Step Size
VS=±5V
4
AV=1
3
RL=10kΩ
CL=12pF
2
TA=25°C
1
0
-1
Step Size (V)
-2
-3
-4
RMS
Frequency (Hz)
1M 6M10k 100k
0.1%
0.1%
10 100 1000
Large Signal Transient Response
1V 1µS
Load Capacitance (pF)
VS=±5V
TA=25°C
AV=1
RL=10kΩ
CL=12pF
VS=±5V
TA=25°C
AV=1
RL=10kΩ
CL=12pF
800
200 400
Settling Time (nS)
Small Signal Transient Response
50mV 200ns
6000
8
Page 9
EL5220C, EL5420C
12MHz Rail-to-Rail Input-Output Op Amps
Pin Descriptions
EL5420C EL5220C Pin Name Pin Function Equivalent Circuit
1 1 VOUTA Amplifier A Output
GND
Circuit 1
2 2 VINA- Amplifier A Inverting Input
EL5220C, EL5420C
V
S+
V
S-
V
S+
3 3 VINA+ Amplifier A Non-Inverting Input (Reference Circuit 2)
4 8 VS+ Positive Power Supply
5 5 VINB+ Amplifier B Non-Inverting Input (Reference Circuit 2)
6 6 VINB- Amplifier B Inverting Input (Reference Circuit 2)
7 7 VOUTB Amplifier B Output (Reference Circuit 1)
8 VOUTC Amplifier C Output (Reference Circuit 1)
9 VINC- Amplifier C Inverting Input (Reference Circuit 2)
10 VINC+ Amplifier C Non-Inverting Input (Reference Circuit 2)
11 4 VS- Negative Power Supply
12 VIND+ Amplifier D Non-Inverting Input (Reference Circuit 2)
13 VIND- Amplifier D Inverting Input (Reference Circuit 2)
14 VOUTD Amplifier D Output (Reference Circuit 1)
Circuit 2
V
S-
9
Page 10
EL5220C, EL5420C
12MHz Rail-to-Rail Input-Output Op Amps
Applications Information
Product Description
EL5220C, EL5420C
The EL5220C and EL5420C voltage feedback amplifiers are fabricated using a high voltage CMOS process.
They exhibit rail-to-rail input and output capability, they
are unity gain stable, and have low power consumption
(500µA per amplifier). These features make the
EL5220C and EL5420C ideal for a wide range of general-purpose applications. Connected in voltage follower
mode and driving a load of 10kΩ and 12pF, the
EL5220C and EL5420C have a -3dB bandwidth of
12MHz while maintaining a 10V/µs slew rate. The
EL5220C is a dual amplifier while the EL5420C is a
quad amplifier.
VS=±5V
TA=25°C
AV=1
VIN=10V
P-P
Output Input
Figure 1. Operation with Rail-to-Rail Input and
Output
Operating Voltage, Input, and Output
The EL5220C and EL5420C are specified with a single
nominal supply voltage from 5V to 15V or a split supply
with its total range from 5V to 15V. Correct operation is
guaranteed for a supply range of 4.5V to 16.5V. Most
EL5220C and EL5420C specifications are stable over
both the full supply range and operating temperatures of
-40 °C to +85 °C. Parameter variations with operating
voltage and/or temperature are shown in the typical performance curves.
The input common-mode voltage range of the EL5220C
and EL5420C extends 500mV beyond the supply rails.
The output swings of the EL5220C and EL5420C typically extend to within 80mV of positive and negative
supply rails with load currents of 5mA. Decreasing load
currents will extend the output voltage range even closer
to the supply rails. Figure 1 shows the input and output
waveforms for the device in the unity-gain configura-
tion. Operation is from ±5V supply with a 10kΩ load
connected to GND. The input is a 10V
output voltage is approximately 9.985V
sinusoid. The
P-P
.
P-P
Short Circuit Current Limit
The EL5220C and EL5420C will limit the short circuit
current to ±120mA if the output is directly shorted to the
positive or the negative supply. If an output is shorted
indefinitely, the power dissipation could easily increase
such that the device may be damaged. Maximum reliability is maintained if the output continuous current
never exceeds ±30 mA. This limit is set by the design of
the internal metal interconnects.
Output Phase Reversal
The EL5220C and EL5420C are immune to phase reversal as long as the input voltage is limited from (VS-) ----
-0.5V to (VS+) +0.5V. Figure 2 shows a photo of the
output of the device with the input voltage driven
beyond the supply rails. Although the device's output
will not change phase, the input's overvoltage should be
avoided. If an input voltage exceeds supply voltage by
more than 0.6V, electrostatic protection diodes placed in
the input stage of the device begin to conduct and overvoltage damage could occur.
10
Page 11
1V 100µs
VS=±2.5V
TA=25°C
AV=1
VIN=6V
P-P
1V
Figure 2. Operation with Beyond-the-Rails
Input
Power Dissipation
With the high-output drive capability of the EL5220C
and EL5420C amplifiers, it is possible to exceed the
125°C “absolute-maximum junction temperature” under
certain load current conditions. Therefore, it is important
to calculate the maximum junction temperature for the
application to determine if load conditions need to be
modified for the amplifier to remain in the safe operating
area.
The maximum power dissipation allowed in a package is
determined according to:
T
–
JMAXTAMAX
P
DMAX
where:
T
= Maximum Junction Temperature
JMAX
T
= Maximum Ambient Temperature
AMAX
θ
= Thermal Resistance of the Package
JA
P
= Maximum Power Dissipation in the Package
DMAX
The maximum power dissipation actually produced by
an IC is the total quiescent supply current times the total
power supply voltage, plus the power in the IC due to the
loads, or:
------------------------------------------------
=
Θ
JA
EL5220C, EL5420C
12MHz Rail-to-Rail Input-Output Op Amps
when sourcing, and:
P
when sinking.
where
i = 1 to 2 for Dual and 1 to 4 for Quad
VS = Total Supply Voltage
I
SMAX
V
OUT
I
LOAD
If we set the two P
we can solve for R
ures 3, 4, and 5 provide a convenient way to see if the
device will overheat. The maximum safe power dissipation can be found graphically, based on the package type
and the ambient temperature. By using the previous
equation, it is a simple matter to see if P
the device's power derating curves. To ensure proper
operation, it is important to observe the recommended
derating curves in Figures 3, 4, and 5.
Power Dissipation (mW)
Figure 3. Package Power Dissipation vs
DMAX
ΣiV
SISMAXVOUT
i( VS- ) I
LOAD
= Maximum Supply Current Per Amplifier
i = Maximum Output Voltage of the Application
i = Load Current
equations equal to each other,
DMAX
i to avoid device overheat. Fig-
LOAD
exceeds
DMAX
JEDEC JESD51-7 High Effective Thermal Conductivity (4Layer) Test Board
LPP exposed diepad soldered to PCB per JESD51-5
1200
1000
800
600
400
200
0
1.136W
1.0W
870mW
0
TSSOP14
θJA=100°C/W
MSOP8
θJA=115°C/W
25 50 75 100 125 15085
Ambient Temperature (°C)
MAX TJ=125°C
SO14
θJA=88°C/W
Ambient Temperature
i×–+×[]×=
EL5220C, EL5420C
P
DMAX
ΣiV
SISMAXVS
+( V
OUT
i ) I
LOAD
i×–+×[]×=
11
Page 12
EL5220C, EL5420C
12MHz Rail-to-Rail Input-Output Op Amps
JEDEC JESD51-3 and SEMI G42-88 (Single Layer) Test
Board
1200
EL5220C, EL5420C
1000
833mW
800
667mW
600
606mW
485mW
400
Power Dissipation (mW)
200
0
0
SO14
θJA=120°C/W
MSOP8
θJA=206°C/W
25 50 75 100 125 15085
Ambient Temperature (°C)
LPP16
θJA=150°C/W
Figure 4. Package Power Dissipation vs
Ambient Temperature
JEDEC JESD51-7 High Effective Thermal Conductivity (4Layer) Test Board
(LPP exposed diepad soldered to PCB per JESD51-5)
3
2.500W
2.5
2
1.5
1
Power Dissipation (W)
0.5
0
0 25 50 75 100 125 150
L
P
P
1
4
6
0
°
C
/
W
85
Ambient Temperature (°C)
Figure 5. Package Power Dissipation vs
Ambient Temperature
MAX TJ=125°C
TSSOP14
θJA=165°C/W
the peaking increase. The amplifiers drive 10pF loads in
parallel with 10kΩ with just 1.5dB of peaking, and
100pF with 6.4dB of peaking. If less peaking is desired
in these applications, a small series resistor (usually
between 5Ω and 50Ω) can be placed in series with the
output. However, this will obviously reduce the gain
slightly. Another method of reducing peaking is to add a
“snubber” circuit at the output. A snubber is a shunt load
consisting of a resistor in series with a capacitor. Values
of 150Ω and 10nF are typical. The advantage of a snub-
ber is that it does not draw any DC load current or
reduce the gain
Power Supply Bypassing and Printed Circuit
Board Layout
The EL5220C and EL5420C can provide gain at high
frequency. As with any high-frequency device, good
printed circuit board layout is necessary for optimum
performance. Ground plane construction is highly recommended, lead lengths should be as short as possible
and the power supply pins must be well bypassed to
reduce the risk of oscillation. For normal single supply
operation, where the VS- pin is connected to ground, a
0.1µF ceramic capacitor should be placed from VS+ to
pin to VS- pin. A 4.7µF tantalum capacitor should then
be connected in parallel, placed in the region of the
amplifier. One 4.7µF capacitor may be used for multiple
devices. This same capacitor combination should be
placed at each supply pin to ground if split supplies are
to be used.
Unused Amplifiers
It is recommended that any unused amplifiers in a dual
and a quad package be configured as a unity gain follower. The inverting input should be directly connected
to the output and the non-inverting input tied to the
ground plane.
Driving Capacitive Loads
The EL5220C and EL5420C can drive a wide range of
capacitive loads. As load capacitance increases, however, the -3dB bandwidth of the device will decrease and
12
Page 13
EL5220C, EL5420C
12MHz Rail-to-Rail Input-Output Op Amps
EL5220C, EL5420C
General Disclaimer
Specifications contained in this data sheet are in effect as of the publication date shown. Elantec, Inc. reserves the right to make changes in the circuitry or specifications contained herein at any time without notice. Elantec, Inc. assumes no responsibility for the use of any circuits described
herein and makes no representations that they are free from patent infringement.
WARNING - Life Support Policy
Elantec, Inc. products are not authorized for and should not be used
within Life Support Systems without the specific written consent of
Elantec, Inc. Life Support systems are equipment intended to sup-
Elantec Semiconductor, Inc.
675 Trade Zone Blvd.
Milpitas, CA 95035
Telephone: (408) 945-1323
(888) ELANTEC
Fax: (408) 945-9305
European Office: +44-118-977-6020
Japan Technical Center: +81-45-682-5820
port or sustain life and whose failure to perform when properly used
in accordance with instructions provided can be reasonably
expected to result in significant personal injury or death. Users contemplating application of Elantec, Inc. Products in Life Support
Systems are requested to contact Elantec, Inc. factory headquarters
to establish suitable terms & conditions for these applications. Elantec, Inc.’s warranty is limited to replacement of defective
components and does not cover injury to persons or property or
other consequential damages.
September 19, 2001
13
Printed in U.S.A.
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