EL2245CS - Elantec Semiconductor

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.

EL2245C, EL2445C

General Description

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.

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.

The EL2245C/EL2445C also feature an extremely wide output volt-

age swing of ±13.6V with VS = ±15V and RL = 1000Ω. At ±5V,

output voltage swing is a wide ±3.8V with RL = 500Ω and ±3.2V with

RL = 150Ω. Furthermore, for single-supply operation at +5V, output

voltage swing is an excellent 0.3V to 3.8V with RL = 500Ω.

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.

Connection Diagrams

EL2245CN/CS Dual EL2445CN/CS Quad

Features

•100MHz gain-bandwidth at gain-

of-2

•Gain-of-2 stable

•Low supply current (per amplifier)

= 5.2mA at VS = ±15V

•Wide supply range

= ±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

•Low differential gain = 0.02% at

AV=+2, RL = 150Ω

•Low differential phase = 0.07° at

AV = +2, RL = 150Ω

•Stable with unlimited capacitive

load

•Wide output voltage swing

=±13.6V with VS = ±15V,

RL = 1000Ω

= 3.8V/0.3V with VS = +5V,

RL = 500Ω

Applications

•Video amplifier

•Single-supply amplifier

•Active filters/integrators

•High-speed sample-and-hold

•High-speed signal processing

•ADC/DAC buffer

•Pulse/RF amplifier

•Pin diode receiver

•Log amplifier

•Photo multiplier amplifier

•Difference amplifier

Ordering Information

Part No. Temp. Range Package Outline #

EL2245CN -40°C to +85°C 8-Pin P-DIP MDP0031

EL2245CS -40°C to +85°C 8-Lead SO MDP0027

EL2445CN -40°C to +85°C 14-Pin P-DIP MDP0031

EL2445CS -40°C to +85°C 14-Lead SO MDP0027

EL2245C, EL2445C

Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp

September 26, 2001

EL2245C, EL2445C

Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp

EL2245C, EL2445C

Absolute Maximum Ratings (TA = 25°C)

Supply Voltage (VS)±18V or 36V

Peak Output Current (IOP)Short-Circuit Protected

Output Short-Circuit Duration Infinite

A heat-sink is required to keep junction temperature below

absolute maximum when an output is shorted.

Input Voltage (VIN) ±VS

Differential Input Voltage (dVIN)±10V

Power Dissipation (PD)See Curves

Operating Temperature Range (TA)0°C to +75°C

Operating Junction Temperature (TJ)150°C

Storage Temperature (TST)-65°C to +150°C

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 = 1000Ω, unless otherwise specified

Parameter Description Condition Temp Min Typ Max Unit

VOS Input Offset

Voltage

VS = ±15V 25°C 0.5 4.0 mV

TMIN, TMAX 6.0 mV

TCVOS Average Offset Voltage Drift [1] All 10.0 µV/°C

IBInput Bias VS = ±15V 25°C 2.8 8.2 µA

Current TMIN, TMAX 9.2 µA

VS = ±5V 25°C 2.8 µA

IOS Input Offset

Current

VS = ±15V 25°C 50 300 nA

TMIN, TMAX 400 nA

VS = ±5V 25°C 50 nA

TCIOS Average Offset Current Drift [1] All 0.3 nA/°C

AVOL Open-Loop Gain VS = ±15V,VOUT = ±10V, RL = 1000Ω25°C 1500 3000 V/V

TMIN, TMAX 1500 V/V

VS = ±5V, VOUT = ±2.5V, RL = 500Ω25°C 2500 V/V

VS = ±5V, VOUT = ±2.5V, RL = 150Ω25°C 1750 V/V

PSRR Power Supply

Rejection Ratio

VS = ±5V to ±15V 25°C 65 80 dB

TMIN, TMAX 60 dB

CMRR Common-Mode VCM = ±12V, VOUT = 0V 25°C 70 90 dB

Rejection Ratio TMIN, TMAX 70 dB

CMIR Common-Mode

Input Range

VS = ±15V 25°C ±14.0 V

VS = ±5V 25°C ±4.2 V

VS = +5V 25°C 4.2/0.1 V

VOUT Output Voltage

Swing

VS = ±15V, RL = 1000Ω25°C ±13.4 ±13.6 V

TMIN, TMAX ±13.1 V

VS = ±15V, RL = 500Ω25°C ±12.0 ±13.4 V

VS = ±5V, RL = 500Ω25°C ±3.4 ±3.8 V

VS = ±5V, RL = 150Ω25°C ±3.2 V

VS = +5V, RL = 500Ω25°C 3.6/0.4 3.8/0.3 V

TMIN, TMAX 3.5/0.5 V

ISC Output Short

Circuit Current

25°C 40 75 mA

TMIN, TMAX 35 mA

ISSupply Current

(Per Amplifier)

VS = ±15V, No Load 25°C 5.2 7 mA

TMIN 7.6 mA

TMAX 7.6 mA

VS = ±5V, No Load 25°C 5.0 mA

EL2245C, EL2445C

Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp

EL2245C, EL2445C

RIN Input Resistance Differential 25°C 150 kΩ

Common-Mode 25°C 15 MΩ

CIN Input Capacitance AV = +1@ 10MHz 25°C 1.0 pF

ROUT Output Resistance AV = +1 25°C 50 mΩ

PSOR Power-Supply

Operating Range

Dual-Supply 25°C ±2.0 ±18.0 V

Single-Supply 25°C 2.5 36.0 V

1. Measured from TMIN to TMAX.

DC Electrical Characteristics (Continued)

VS = ±15V, RL = 1000Ω, unless otherwise specified

Parameter Description Condition Temp Min Typ Max Unit

Closed-Loop AC Electrical Characteristics

VS = ±15V, AV = +2, RL = 1000Ω unless otherwise specified

Parameter Description Condition Temp Min Typ Max Unit

BW -3dB Bandwidth

(VOUT = 0.4VPP)

VS = ±15V, AV = +2 25°C 100 MHz

VS = ±15V, AV = -1 25°C 75 MHz

VS = ±15V, AV = +5 25°C 20 MHz

VS = ±15V, AV = +10 25°C 10 MHz

VS = ±15V, AV = +20 25°C 5MHz

VS = ±5V, AV = +2 25°C 75 MHz

GBWP Gain-Bandwidth Product VS = ±15V 25°C 200 MHz

VS = ±5V 25°C 150 MHz

PM Phase Margin RL = 1 kΩ, CL = 10pF 25°C 50 °

CS Channel Separation f = 5MHz 25°C 85 dB

SR Slew Rate [1] VS = ±15V, RL = 1000Ω25°C 200 275 V/µs

VS = ±5V, RL = 500Ω25°C 200 V/µs

FPBW Full-Power Bandwidth [2] VS = ±15V 25°C 3.2 4.4 MHz

VS = ±5V 25°C 12.7 MHz

tr, tfRise Time, Fall Time 0.1V Step 25°C 3.0 ns

OS Overshoot 0.1V Step 25°C 20 %

tPD Propagation Delay 25°C 2.5 ns

tsSettling to +0.1%

(AV = +1)

VS = ±15V, 10V Step 25°C 80 ns

VS = ±5V, 5V Step 25°C 60 ns

dG Differential Gain [3] NTSC/PAL 25°C 0.02 %

dP Differential Phase [3] NTSC/PAL 25°C 0.07 °

eN Input Noise Voltage 10kHz 25°C 15.0 nV√Hz

iN Input Noise Current 10kHz 25°C 1.50 pA√Hz

CI STAB Load Capacitance Stability AV = +1 25°C Infinite pF

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/(2π *

Vpeak).

3. Video Performance measured at VS = ±15V, AV = +2 with 2 times normal video level across RL = 150Ω. This corresponds to standard video levels

across a back-terminated 75Ω load. For other values of RL, see curves.

EL2245C, EL2445C

Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp

EL2245C, EL2445C

Test Circuit

EL2245C, EL2445C

Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp

EL2245C, EL2445C

Typical Performance Curves

Non-Inverting

Frequency Response Inverting Frequency Response Frequency Response for

Various Load Resistances

Equivalent Input Noise

Output Voltage Swing

vs Frequency

Open-Loop Gain and

Phase vs Frequency

CMRR, PSRR and Closed-Loop

Output Resistance vs

Frequency 2nd and 3rd Harmonic

Distortion vs Frequency Settling Time vs

Output Voltage Change

Supply Current vs

Supply Voltage Common-Mode Input Range vs

Supply Voltage Output Voltage Range

vs Supply Voltage

EL2245C, EL2445C

Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp

EL2245C, EL2445C

Gain-Bandwidth Product

vs Supply Voltage Open-Loop Gain

vs Supply Voltage Slew-Rate vs

Supply Voltage

Voltage Swing

vs Load Resistance

Open-Loop Gain

vs Load Resistance

Bias and Offset Current

vs Input Common-Mode Voltage

Offset Voltage

vs Temperature Bias and Output

Current vs Temperature Supply Current

vs Temperature

Slew Rate vs

Temperature

Open-Loop Gain PSRR

and CMRR vs Temperature

Gain-Bandwidth Product

vs Temperature

EL2245C, EL2445C

Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp

EL2245C, EL2445C

Short-Circuit Current

vs Temperature Gain-Bandwidth Product

vs Load Capacitance Overshoot vs

Load Capacitance

Small-Signal

Step Response Large-Signal

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

150Ω Loads at 3.58MHz

Differential Gain and

Phase vs Number of

150Ω Loads at 4.43MHz

8-Pin Plastic DIP

Maximum Power Dissipation vs Ambient

Temperature

8-Lead SO

Maximum Power Dissipation

vs Ambient Temperature

EL2245C, EL2445C

Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp

EL2245C, EL2445C

Simplified Schematic (Per Amplifier)

Burn-In Circuit (Per Amplifier)

14-Pin Plastic DIP

Maximum Power Dissipation

vs Ambient Temperature

14-Lead SO

Maximum Power Dissipation

vs Ambient Temperature Channel Separation

vs Frequency

All Packages Use the Same Schematic

EL2245C, EL2445C

Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp

EL2245C, EL2445C

Applications Information

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.

Power Dissipation

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:

TJmax = Tmax + (θJA* (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

θJA =Thermal Resistance of the Package

PDmax =Maximum Power Dissipation of 1Amplifier

VS =Supply Voltage

ISmax =Maximum Supply Current of 1Amplifier

Voutmax =Maximum Output Voltage Swing of the

Application

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

θJAs 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 = 150Ω, giving the results seen

in Table 1.

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 = 500Ω), 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 = 500Ω. 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.

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-

Table 1

Duals Package θJA Max PDiss @ Tmax Max VS

EL2245CN PDIP8 95°C/W 0.789W @ 75°C ±16.6V

EL2245CS SO8 150°C/W 0.500W @ 75°C ±10.7V

QUADS

EL2445CN PDIP14 70°C/W 1.071W @ 75°C ±11.5V

EL2445CS SO14 110°C/W 0.682W @ 75°C ±7.5V

EL2245C, EL2445C

Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp

EL2245C, EL2445C

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 1000Ω load.

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.

For signal transmission and distribution, a back-termi-

nated cable (75Ω in series at the drive end, and 75Ω 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 150Ω, 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

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

150Ω 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.

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.

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

EL2245C, EL2445C

Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp

EL2245C, EL2445C

good AC performance, parasitic capacitances should be

kept to a minimum at both inputs and at the output.

Resistor values should be kept under 5kΩ 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 EL2245C/EL2445C Macromodel

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-

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.

The model does not simulate these characteristics

accurately:

noise non-linearities

settling-time temperature effects

CMRR manufacturing variations

PSRR

EL2245C, EL2445C

Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp

EL2245C, EL2445C

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

EL2245C, EL2445C

Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp

EL2245C, EL2445C

EL2245C/EL2445C Macromodel

EL2245C/EL2445C Model

EL2245C, EL2445C

Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp

EL2245C, EL2445C

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.

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-

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 con-

templating 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. 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.

September 26, 2001

Printed in U.S.A.

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