EL2245 [ELANTEC]
Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp; 双/四通道，低功耗的100MHz增益- 2稳定运算放大器
| 型号： | EL2245 |
| 厂家： | 
ELANTEC SEMICONDUCTOR |
| 描述： | Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp |
| 文件： | 总14页 (文件大小：449K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
EL2245C, EL2445C
Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp
Features
General Description
• 100MHz gain-bandwidth at gain-
of-2
• Gain-of-2 stable
• Low supply current (per amplifier)
= 5.2mA at VS = ±15V
• Wide supply range
The EL2245C/EL2445C are dual and quad versions of the popular
EL2045C. They are high speed, low power, low cost monolithic oper-
ational amplifiers built on Elantec's proprietary complementary
bipolar process. The EL2245C/EL2445C are gain-of-2 stable and fea-
ture a 275V/µs slew rate and 100MHz bandwidth at gain-of-2 while
requiring only 5.2mA of supply current per amplifier.
= ±2V to ±18V dual-supply
= 2.5V to 36V single-supply
• High slew rate = 275V/µs
• Fast settling = 80ns to 0.1% for a
10V step
The power supply operating range of the EL2245C/EL2445C is from
±18V down to as little as ±2V. For single-supply operation, the
EL2245C/EL2445C operate from 36V down to as little as 2.5V. The
excellent power supply operating range of the EL2245C/EL2445C
makes them an obvious choice for applications on a single +5V or
+3V supply.
• Low differential gain = 0.02% at
AV = +2, RL = 150W
The EL2245C/EL2445C also feature an extremely wide output volt-
age swing of ±13.6V with VS = ±15V and RL = 1000W. At ±5V,
output voltage swing is a wide ±3.8V with RL = 500W and ±3.2V with
RL = 150W. Furthermore, for single-supply operation at +5V, output
voltage swing is an excellent 0.3V to 3.8V with RL = 500W.
• Low differential phase = 0.07° at
AV = +2, RL = 150W
• Stable with unlimited capacitive
load
• Wide output voltage swing
=±13.6V with VS = ±15V,
RL = 1000W
At a gain of +2, the EL2245C/EL2445C have a -3dB bandwidth of
100MHz with a phase margin of 50°. They can drive unlimited load
capacitance, and because of their conventional voltage-feedback
topology, the EL2245C/EL2445C allow the use of reactive or non-lin-
ear elements in their feedback network. This versatility combined with
low cost and 75mA of output-current drive make the
EL2245C/EL2445C an ideal choice for price-sensitive applications
requiring low power and high speed.
= 3.8V/0.3V with VS = +5V,
RL = 500W
Applications
• Video amplifier
• Single-supply amplifier
• Active filters/integrators
• High-speed sample-and-hold
• High-speed signal processing
• ADC/DAC buffer
Connection Diagrams
• Pulse/RF amplifier
EL2245CN/CS Dual
EL2445CN/CS Quad
• Pin diode receiver
• Log amplifier
• Photo multiplier amplifier
• Difference amplifier
Ordering Information
Part No.
EL2245CN
EL2245CS
EL2445CN
EL2445CS
Temp. Range
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
Package
8-Pin P-DIP
8-Lead SO
Outline #
MDP0031
MDP0027
MDP0031
MDP0027
14-Pin P-DIP
14-Lead SO
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.
EL2245C, EL2445C
Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp
Absolute Maximum Ratings (T = 25°C)
A
Supply Voltage (VS)
±18V or 36V
Short-Circuit Protected
Infinite
Differential Input Voltage (dVIN
Power Dissipation (PD
Operating Temperature Range (TA
Operating Junction Temperature (TJ)
Storage Temperature (TST
)
±10V
See Curves
Peak Output Current (IOP
)
)
Output Short-Circuit Duration
)
0°C to +75°C
150°C
A heat-sink is required to keep junction temperature below
absolute maximum when an output is shorted.
)
-65°C to +150°C
Input Voltage (VIN)
±VS
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 = TA.
DC Electrical Characteristics
VS = ±15V, RL = 1000W, unless otherwise specified
Parameter
Description
Input Offset
Condition
Temp
25°C
Min
Typ
Max
4.0
Unit
mV
mV
µV/°C
µA
µA
µA
nA
nA
nA
nA/°C
V/V
V/V
V/V
V/V
dB
VOS
VS = ±15V
0.5
Voltage
TMIN, TMAX
All
6.0
[1]
TCVOS
IB
Average Offset Voltage Drift
Input Bias
10.0
2.8
VS = ±15V
25°C
8.2
9.2
Current
TMIN, TMAX
25°C
VS = ±5V
2.8
50
IOS
Input Offset
Current
VS = ±15V
25°C
300
400
TMIN, TMAX
25°C
VS = ±5V
[1]
50
0.3
TCIOS
AVOL
Average Offset Current Drift
Open-Loop Gain
All
VS = ±15V,VOUT = ±10V, RL = 1000W
25°C
1500
1500
3000
TMIN, TMAX
25°C
VS = ±5V, VOUT = ±2.5V, RL = 500W
VS = ±5V, VOUT = ±2.5V, RL = 150W
VS = ±5V to ±15V
2500
1750
80
25°C
PSRR
CMRR
CMIR
Power Supply
25°C
65
60
70
70
Rejection Ratio
TMIN, TMAX
25°C
dB
Common-Mode
Rejection Ratio
Common-Mode
Input Range
VCM = ±12V, VOUT = 0V
90
dB
TMIN, TMAX
25°C
dB
VS = ±15V
±14.0
±4.2
V
VS = ±5V
25°C
V
VS = +5V
25°C
4.2/0.1
±13.6
V
VOUT
Output Voltage
Swing
VS = ±15V, RL = 1000W
25°C
±13.4
±13.1
±12.0
±3.4
V
TMIN, TMAX
25°C
V
VS = ±15V, RL = 500W
VS = ±5V, RL = 500W
VS = ±5V, RL = 150W
VS = +5V, RL = 500W
±13.4
±3.8
V
25°C
V
25°C
±3.2
V
25°C
3.6/0.4
3.5/0.5
40
3.8/0.3
V
TMIN, TMAX
25°C
V
ISC
Output Short
75
mA
mA
mA
mA
mA
mA
Circuit Current
TMIN, TMAX
25°C
35
IS
Supply Current
(Per Amplifier)
VS = ±15V, No Load
5.2
7
TMIN
7.6
7.6
TMAX
VS = ±5V, No Load
25°C
5.0
2
EL2245C, EL2445C
Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp
DC Electrical Characteristics (Continued)
VS = ±15V, RL = 1000W, unless otherwise specified
Parameter
Description
Input Resistance
Condition
Temp
25°C
25°C
25°C
25°C
25°C
25°C
Min
Typ
150
15
Max
Unit
kW
MW
pF
RIN
Differential
Common-Mode
AV = +1@ 10MHz
AV = +1
CIN
Input Capacitance
1.0
50
ROUT
PSOR
Output Resistance
Power-Supply
mW
V
Dual-Supply
±2.0
2.5
±18.0
36.0
Operating Range
Single-Supply
V
1. Measured from TMIN to TMAX
.
Closed-Loop AC Electrical Characteristics
VS = ±15V, AV = +2, RL = 1000W unless otherwise specified
Parameter
Description
-3dB Bandwidth
(VOUT = 0.4VPP
Condition
VS = ±15V, AV = +2
VS = ±15V, AV = -1
VS = ±15V, AV = +5
VS = ±15V, AV = +10
VS = ±15V, AV = +20
VS = ±5V, AV = +2
VS = ±15V
Temp
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
Min
Typ
Max
Unit
MHz
MHz
MHz
MHz
MHz
MHz
MHz
MHz
°
BW
100
75
)
20
10
5
75
GBWP
Gain-Bandwidth Product
200
150
50
VS = ±5V
PM
CS
SR
Phase Margin
RL = 1 kW, CL = 10pF
f = 5MHz
Channel Separation
Slew Rate [1]
85
dB
VS = ±15V, RL = 1000W
VS = ±5V, RL = 500W
VS = ±15V
200
3.2
275
200
4.4
12.7
3.0
20
V/µs
V/µs
MHz
MHz
ns
FPBW
Full-Power Bandwidth [2]
VS = ±5V
tr, tf
OS
tPD
ts
Rise Time, Fall Time
Overshoot
0.1V Step
0.1V Step
%
Propagation Delay
2.5
80
ns
Settling to +0.1%
(AV = +1)
VS = ±15V, 10V Step
VS = ±5V, 5V Step
NTSC/PAL
NTSC/PAL
10kHz
ns
60
ns
[3]
dG
Differential Gain
0.02
0.07
15.0
1.50
Infinite
%
[3]
dP
Differential Phase
°
eN
Input Noise Voltage
nVÖHz
pAÖHz
pF
iN
Input Noise Current
10kHz
CI STAB
Load Capacitance Stability
AV = +1
1. Slew rate is measured on rising edge.
2. For VS = ±15V, VOUT = 20VPP. For VS = ±5V, VOUT = 5VPP. Full-power bandwidth is based on slew rate measurement using: FPBW = SR/(2p *
Vpeak).
3. Video Performance measured at VS = ±15V, AV = +2 with 2 times normal video level across RL = 150W. This corresponds to standard video levels
across a back-terminated 75W load. For other values of RL, see curves.
3
EL2245C, EL2445C
Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp
Test Circuit
4
EL2245C, EL2445C
Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp
Typical Performance Curves
Non-Inverting
Frequency Response
Inverting Frequency Response
Frequency Response for
Various Load Resistances
Open-Loop Gain and
Phase vs Frequency
Output Voltage Swing
vs Frequency
Equivalent Input Noise
CMRR, PSRR and Closed-Loop
Output Resistance vs
Frequency
2nd and 3rd Harmonic
Distortion vs Frequency
Settling Time vs
Output Voltage Change
Common-Mode Input Range vs
Supply Voltage
Supply Current vs
Supply Voltage
Output Voltage Range
vs Supply Voltage
5
EL2245C, EL2445C
Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp
Gain-Bandwidth Product
vs Supply Voltage
Open-Loop Gain
vs Supply Voltage
Slew-Rate vs
Supply Voltage
Bias and Offset Current
Open-Loop Gain
Voltage Swing
vs Input Common-Mode Voltage
vs Load Resistance
vs Load Resistance
Offset Voltage
vs Temperature
Bias and Output
Current vs Temperature
Supply Current
vs Temperature
Gain-Bandwidth Product
vs Temperature
Open-Loop Gain PSRR
and CMRR vs Temperature
Slew Rate vs
Temperature
6
EL2245C, EL2445C
Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp
Short-Circuit Current
vs Temperature
Gain-Bandwidth Product
vs Load Capacitance
Overshoot vs
Load Capacitance
Small-Signal
Large-Signal
Step Response
Step Response
Differential Gain and
Phase vs DC Input
Offset at 3.58MHz
Differential Gain and
Phase vs DC Input
Offset at 4.43MHz
Differential Gain and
Phase vs Number of
150W Loads at 3.58MHz
8-Lead SO
Maximum Power Dissipation
vs Ambient Temperature
Differential Gain and
Phase vs Number of
150W Loads at 4.43MHz
8-Pin Plastic DIP
Maximum Power Dissipation vs Ambient
Temperature
7
EL2245C, EL2445C
Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp
14-Pin Plastic DIP
14-Lead SO
Maximum Power Dissipation
vs Ambient Temperature
Maximum Power Dissipation
vs Ambient Temperature
Channel Separation
vs Frequency
Simplified Schematic (Per Amplifier)
Burn-In Circuit (Per Amplifier)
All Packages Use the Same Schematic
8
EL2245C, EL2445C
Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp
Applications Information
Voutmax =Maximum Output Voltage Swing of the
Application
Product Description
The EL2245C/EL2445C are dual and quad low-power
wideband monolithic operational amplifiers built on
Elantec's proprietary high-speed complementary bipolar
process. The EL2245C/EL2445C use a classical volt-
age-feedback topology which allows them to be used in
a variety of applications where current-feedback ampli-
fiers are not appropriate because of restrictions placed
upon the feedback element used with the amplifier. The
conventional topology of the EL2245C/EL2445C
allows, for example, a capacitor to be placed in the feed-
back path, making it an excellent choice for applications
such as active filters, sample-and-holds, or integrators.
Similarly, because of the ability to use diodes in the
feedback network, the EL2245C/EL2445C are an excel-
lent choice for applications such as fast log amplifiers.
RL =Load Resistance
To serve as a guide for the user, we can calculate maxi-
mum allowable supply voltages for the example of the
video cable-driver below since we know that TJmax
=
150°C, Tmax = 75°C, ISmax = 7.6mA, and the package
qJAs are shown in Table 1. If we assume (for this exam-
ple) that we are driving a back-terminated video cable,
then the maximum average value (over duty-cycle) of
Voutmax is 1.4V, and RL = 150W, giving the results seen
in Table 1.
Table 1
Duals
EL2245CN
EL2245CS
QUADS
Package
PDIP8
qJA
Max PDiss @ Tmax Max VS
95°C/W
150°C/W
0.789W @ 75°C
0.500W @ 75°C
±16.6V
±10.7V
SO8
Power Dissipation
EL2445CN
EL2445CS
PDIP14
SO14
70°C/W
1.071W @ 75°C
0.682W @ 75°C
±11.5V
±7.5V
With the wide power supply range and large output drive
capability of the EL2245C/EL2445C, it is possible to
exceed the 150°C maximum junction temperatures
under certain load and power-supply conditions. It is
therefore important to calculate the maximum junction
temperature (TJmax) for all applications to determine if
power supply voltages, load conditions, or package type
need to be modified for the EL2245C/EL2445C to
remain in the safe operating area. These parameters are
related as follows:
110°C/W
Single-Supply Operation
The EL2245C/EL2445C have been designed to have a
wide input and output voltage range. This design also
makes the EL2245C/EL2445C an excellent choice for
single-supply operation. Using a single positive supply,
the lower input voltage range is within 100mV of ground
(RL = 500W), and the lower output voltage range is
within 300 mV of ground. Upper input voltage range
reaches 4.2V, and output voltage range reaches 3.8V
with a 5V supply and RL = 500W. This results in a 3.5V
output swing on a single 5V supply. This wide output
voltage range also allows single-supply operation with a
supply voltage as high as 36V or as low as 2.5V. On a
single 2.5V supply, the EL2245C/EL2445C still have
1V of output swing.
TJmax = Tmax + (qJA* (PDmaxtotal))
where PDmaxtotal is the sum of the maximum power
dissipation of each amplifier in the package (PDmax).
PDmax for each amplifier can be calculated as follows:
PDmax= (2*VS*ISmax+(VS-Voutmax)*(Voutmax/RL))
where:
Tmax =Maximum Ambient Temperature
qJA =Thermal Resistance of the Package
PDmax =Maximum Power Dissipation of 1 Amplifier
VS =Supply Voltage
Gain-Bandwidth Product and the -3dB
Bandwidth
The EL2245C/EL2445C have a bandwidth at gain-of-2
of 100MHz while using only 5.2mA of supply current
per amplifier. For gains greater than 4, their closed-loop
-3dB bandwidth is approximately equal to the gain-
ISmax =Maximum Supply Current of 1Amplifier
9
EL2245C, EL2445C
Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp
bandwidth product divided by the noise gain of the cir-
cuit. For gains less than 4, higher-order poles in the
amplifiers' transfer function contribute to even higher
closed loop bandwidths. For example, the
EL2245C/EL2445C have a -3dB bandwidth of 100MHz
at a gain of +2, dropping to 20MHz at a gain of +5. It is
important to note that the EL2245C/EL2445C have been
designed so that this “extra” bandwidth in low-gain
applications does not come at the expense of stability.
As seen in the typical performance curves, the
EL2245C/EL2445C in a gain of +2 only exhibit 1.0dB
of peaking with a 1000W load.
characterized over the entire DC offset range from -
0.714V to +0.714V. For more information, refer to the
curves of dG and dP vs DC Input Offset.
Output Drive Capability
The EL2245C/EL2445C have been designed to drive
low impedance loads. They can easily drive 6VPP into a
150W load. This high output drive capability makes the
EL2245C/EL2445C an ideal choice for RF, IF and video
applications. Furthermore, the current drive of the
EL2245C/EL2445C remains a minimum of 35mA at
low temperatures. The EL2245C/EL2445C are current-
limited at the output, allowing it to withstand shorts to
ground. However, power dissipation with the output
shorted can be in excess of the power-dissipation capa-
bilities of the package.
Video Performance
An industry-standard method of measuring the video
distortion of components such as the EL2245C/
EL2445C is to measure the amount of differential gain
(dG) and differential phase (dP) that they introduce. To
make these measurements, a 0.286VPP (40 IRE) signal is
applied to the device with 0V DC offset (0 IRE) at either
3.58MHz for NTSC or 4.43MHz for PAL. A second
measurement is then made at 0.714V DC offset (100
IRE). Differential gain is a measure of the change in
amplitude of the sine wave, and is measured in percent.
Differential phase is a measure of the change in phase,
and is measured in degrees.
Capacitive Loads
For ease of use, the EL2245C/EL2445C have been
designed to drive any capacitive load. However, the
EL2245C/EL2445C remain stable by automatically
reducing their gain-bandwidth product as capacitive
load increases. Therefore, for maximum bandwidth,
capacitive loads should be reduced as much as possible
or isolated via a series output resistor (Rs). Similarly,
coax lines can be driven, but best AC performance is
obtained when they are terminated with their character-
istic impedance so that the capacitance of the coaxial
cable will not add to the capacitive load seen by the
amplifier. Although stable with all capacitive loads,
some peaking still occurs as load capacitance increases.
A series resistor at the output of the EL2245C/EL2445C
can be used to reduce this peaking and further improve
stability.
For signal transmission and distribution, a back-termi-
nated cable (75W in series at the drive end, and 75W to
ground at the receiving end) is preferred since the
impedance match at both ends will absorb any reflec-
tions. However, when double termination is used, the
received signal is halved; therefore a gain of 2 configu-
ration is typically used to compensate for the
attenuation.
The EL2245C/EL2445C have been designed as an eco-
nomical solution for applications requiring low video
distortion. They have been thoroughly characterized for
video performance in the topology described above, and
the results have been included as typical dG and dP
specifications and as typical performance curves. In a
gain of +2, driving 150W, with standard video test levels
at the input, the EL2245C/EL2445C exhibit dG and dP
of only 0.02% and 0.07° at NTSC and PAL. Because dG
and dP can vary with different DC offsets, the video per-
formance of the EL2245C/EL2445C has been
Printed-Circuit Layout
The EL2245C/EL2445C are well behaved, and easy to
apply in most applications. However, a few simple tech-
niques will help assure rapid, high quality results. As
with any high-frequency device, good PCB layout is
necessary for optimum performance. Ground-plane con-
struction is highly recommended, as is good power
supply bypassing. A 0.1µF ceramic capacitor is recom-
mended for bypassing both supplies. Lead lengths
should be as short as possible, and bypass capacitors
should be as close to the device pins as possible. For
10
EL2245C, EL2445C
Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp
good AC performance, parasitic capacitances should be
tor (copywritten by the Microsim Corporation), and may
need to be rearranged for other simulators. It approxi-
mates DC, AC, and transient response for resistive
loads, but does not accurately model capacitive loading.
This model is slightly more complicated than the models
used for low-frequency op-amps, but it is much more
accurate for AC analysis.
kept to a minimum at both inputs and at the output.
Resistor values should be kept under 5kW because of the
RC time constants associated with the parasitic capaci-
tance. Metal-film and carbon resistors are both
acceptable, use of wire-wound resistors is not recom-
mended because of their parasitic inductance. Similarly,
capacitors should be low-inductance for best
performance.
The model does not simulate these characteristics
accurately:
The EL2245C/EL2445C Macromodel
noise
non-linearities
settling-time
CMRR
PSRR
temperature effects
manufacturing variations
This macromodel has been developed to assist the user
in simulating the EL2245C/EL2445C with surrounding
circuitry. It has been developed for the PSPICE simula-
11
EL2245C, EL2445C
Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp
EL2245C/EL2445C Macromodel
* Connections: +input
*
*
*
*
*
|
|
|
|
|
-input
|
|
|
|
+Vsupply
|
|
|
-Vsupply
|
output
|
|
.subckt M2245 3
*
2
7
4
6
* Input stage
*
ie 7 37 1mA
r6 36 37 400
r7 38 37 400
rc1 4 30 850
rc2 4 39 850
q1 30 3 36 qp
q2 39 2 38 qpa
ediff 33 0 39 30 1.0
rdiff 33 0 1Meg
*
* Compensation Section
*
ga 0 34 33 0 1m
rh 34 0 2Meg
ch 34 0 1.3pF
rc 34 40 1K
cc 40 0 1pF
*
* Poles
*
ep 41 0 40 0 1
rpa 41 42 200
cpa 42 0 1pF
rpb 42 43 200
cpb 43 0 1pF
*
* Output Stage
*
ios1 7 50 1.0mA
ios2 51 4 1.0mA
q3 4 43 50 qp
q4 7 43 51 qn
q5 7 50 52 qn
q6 4 51 53 qp
ros1 52 6 25
ros2 6 53 25
*
* Power Supply Current
*
ips 7 4 2.7mA
*
* Models
*
.model qn npn(is=800E-18 bf=200 tf=0.2nS)
.model qpa pnp(is=864E-18 bf=100 tf=0.2nS)
.model qp pnp(is=800E-18 bf=125 tf=0.2nS)
.ends
12
EL2245C, EL2445C
Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp
EL2245C/EL2445C Macromodel
EL2245C/EL2445C Model
13
EL2245C, EL2445C
Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp
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 cir-
cuitry 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.
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within Life Support Systems without the specific written consent of
Elantec, Inc. Life Support systems are equipment intended to sup-
port or sustain life and whose failure to perform when properly used
in accordance with instructions provided can be reasonably
Elantec Semiconductor, Inc.
675 Trade Zone Blvd.
Milpitas, CA 95035
Telephone: (408) 945-1323
(888) ELANTEC
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to establish suitable terms & conditions for these applications. Elan-
tec, Inc.’s warranty is limited to replacement of defective
components and does not cover injury to persons or property or
other consequential damages.
Fax:
(408) 945-9305
European Office: +44-118-977-6020
Japan Technical Center: +81-45-682-5820
Printed in U.S.A.
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