EL2160CN - Elantec Semiconductor

EL2160C December 1995 Rev B

EL2160C

130 MHz Current Feedback Amplifier

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.

Features

#130 MHz 3 dB bandwidth

(AVea

#180 MHz 3 dB bandwidth

(AVea

#0.01% differential gain,

RLe500X

#0.01§differential phase,

RLe500X

#Low supply current, 8.5 mA

#Wide supply range, g2V to g15V

#80 mA output current (peak)

#Low cost

#1500 V/ms slew rate

#Input common mode range to

within 1.5V of supplies

#35 ns settling time to 0.1%

Applications

#Video amplifiers

#Cable drivers

#RGB amplifiers

#Test equipment amplifiers

#Current to voltage converter

Ordering Information

Part No. Temp. Range Package OutlineÝ

EL2160CN b40§Ctoa

85§C 8-Pin P-DIP MDP0031

EL2160CS b40§Ctoa

85§C 8-Pin SOIC MDP0027

General Description

The EL2160C is a current feedback operational amplifier with

b3 dB bandwidth of 130 MHz at a gain of a2. Built using the

Elantec proprietary monolithic complementary bipolar process,

this amplifer uses current mode feedback to achieve more band-

width at a given gain than a conventional voltage feedback op-

erational amplifier.

The EL2160C is designed to drive a double terminated 75Xcoax

cable to video levels. Differential gain and phase are excellent

when driving both loads of 500X(k0.01%/k0.01§) and double

terminated 75Xcables (0.025%/0.1§).

The amplifier can operate on any supply voltage from 4V

(g2V) to 33V (g16.5V), yet consume only 8.5 mA at any sup-

ply voltage. Using industry standard pinouts, the EL2160C is

available in 8-pin P-DIP and 8-pin SO packages. For dual and

quad applications, please see the EL2260C/EL2460C datasheet.

Elantec’s facilities comply with MIL-I-45208A and offer appli-

cable quality specifications. See the Elantec document, QRA-2:

Elantec’s Military ProcessingÐMonolithic Products.

Connection Diagram

EL2160C SO, P-DIP

Packages

2060– 1

Top View

EL2160C

130 MHz Current Feedback Amplifier

Absolute Maximum Ratings

(TAe25§C)

Voltage between VSaand VSba33V

Voltage between aIN and bIN g6V

Current into aIN or bIN 10 mA

Internal Power Dissipation See Curves

Operating Ambient Temperature Range b40§Ctoa

85§C

Operating Junction Temperature

Plastic Packages 150§C

Output Current g50 mA

Storage Temperature Range b65§Ctoa

150§C

Important Note:

All parameters having Min/Max specifications are guaranteed. The Test Level column indicates the specific device testing actually

performed during production and Quality inspection. Elantec performs most electrical tests using modern high-speed automatic test

equipment, specifically the LTX77 Series system. Unless otherwise noted, all tests are pulsed tests, therefore T

Test Level Test Procedure

I100% production tested and QA sample tested per QA test plan QCX0002.

II 100% production tested at T

C and QA sample tested at T

MAX

and T

MIN

per QA test plan QCX0002.

III QA sample tested per QA test plan QCX0002.

IV Parameter is guaranteed (but not tested) by Design and Characterization Data.

VParameter is typical value at T

C for information purposes only.

Open Loop DC Electrical Characteristics

VSeg15V, RLe150X,T

Ae25§C unless otherwise specified

Parameter Description Conditions Temp Limits Test Level Units

Min Typ Max EL2160C

VOS Input Offset Voltage VSeg5V, g15V 25§C 2 10 I mV

TC VOS Average Offset Voltage Full 10 V mV/§C

Drift (Note 1)

aIIN aInput Current VSeg5V, g15V 25§C 0.5 5 I mA

bIIN bInput Current VSeg5V, g15V 25§C 5 25 I mA

CMRR Common Mode Rejection VSeg5V, g15V 25§C5055 II dB

Ratio (Note 2)

bICMR bInput Current Common VSeg5V, g15V 25§C 0.2 5 I mA/V

Mode Rejection (Note 2)

PSRR Power Supply Rejection 25§C7595 II dB

Ratio (Note 3)

bIPSR bInput Current Power 25§C 0.2 5 I mA/V

Supply Rejection (Note 3)

TDis2.5in

EL2160C

130 MHz Current Feedback Amplifier

Open Loop DC Electrical Characteristics

Ð Contd.

VSeg15V, RLe150X,T

Ae25§C unless otherwise specified

Parameter Description Conditions Temp Limits Test Level Units

Min Typ Max EL2160C

ROL Transimpedance VSeg15V 25§C 500 2000 I kX

(Note 4) RLe400X

VSeg5V 25§C 500 1800 I kX

RLe150X

aRIN aInput Resistance 25§C 1.5 3.0 II MX

aCIN aInput Capacitance 25§C 2.5 V pF

CMIR Common Mode Input Range VSeg15V 25§Cg13.5 V V

VSeg5V 25§Cg3.5 V V

VOOutput Voltage Swing RLe400X,25§Cg12 g13.5 I V

VSeg15V

RLe150X,25§Cg12 V V

VSeg15V

RLe150X,25§Cg3.0 g3.7 I V

VSeg5V

ISC Output Short Circuit VSeg5V, 25§C 60 100 150 I mA

Current (Note 5) VSeg15V

ISSupply Current VSeg15V 25§C 8.5 12.0 I mA

VSeg5V 25§C 6.4 9.5 I mA

TDis3.4in

EL2160C

130 MHz Current Feedback Amplifier

Closed Loop AC Electrical Characteristics

VSeg15V, AVea

2, RFe560X,R

Le150X,T

Ae25§C unless otherwise noted

Parameter Description Conditions Limits Test Level Units

Min Typ Max EL2160C

BW b3 dB Bandwidth VSeg15V, AVea

2 130 V MHz

(Note 8) VSeg15V, AVea

1 180 V MHz

VSeg5V, AVea

2 100 V MHz

VSeg5V, AVea

1 110 V MHz

SR Slew Rate RLe400X1000 1500 IV V/ms

(Notes 6, 8) RFe1KX,R

Ge110X1500 V V/ms

RLe400X

tr,t

fRise Time, VOUT eg500mV 2.7 V ns

Fall Time, (Note 8)

tpd Propagation Delay 3.2 V ns

(Note 8)

OS Overshoot (Note 8) VOUT eg500 mV 0 V %

ts0.1% Settling Time VOUT eg10V 35 V ns

(Note 8) AVeb

1, RLe1K

dG Differential Gain RLe150X0.025 V %

(Notes 7, 8) RLe500X0.006 V %

dP Differential Phase RLe150X0.1 V deg (§)

(Notes 7, 8) RLe500X0.005 V deg (§)

Note 1: Measured from TMIN to TMAX.

Note 2: VCM eg10V for VSeg15V and TAe25§C

VCM eg3V for VSeg5V and TAe25§C

Note 3: The supplies are moved from g2.5V to g15V.

Note 4: VOUT eg7V for VSeg15V, and VOUT eg2V for VSeg5V.

Note 5: A heat sink is required to keep junction temperature below absolute maximum when an output is shorted.

Note 6: Slew Rate is with VOUT from a10V to b10V and measured at the 25% and 75% points.

Note 7: DC offset from b0.714V through a0.714V, AC amplitude 286 mVp-p,fe3.58 MHz.

Note 8: All AC tests are performed on a ‘‘warmed up’’ part, except for Slew Rate, which is pulse tested.

TDis3.5in

EL2160C

130 MHz Current Feedback Amplifier

Typical Performance Curves

Response (Gain)

Non-Inverting Frequency

Response (Phase)

Non-Inverting Frequency

for Various RL

Frequency Response

Response (Gain)

Inverting Frequency

Response (Phase)

Inverting Frequency

Various RFand RG

Frequency Response for

Voltage for AVeb

3 dB Bandwidth vs Supply

for AVeb

Peaking vs Supply Voltage

Temperature for AVeb1

3 dB Bandwidth vs

2060– 2

EL2160C

130 MHz Current Feedback Amplifier

Typical Performance Curves

Ð Contd.

Voltage for AVea

3 dB Bandwidth vs Supply

for AVea

Peaking vs Supply Voltage

for AVea

3 dB Bandwidth vs Temperature

Voltage for AVea

3 dB Bandwidth vs Supply

for AVea

Peaking vs Supply Voltage

for AVea

3 dB Bandwidth vs Temperature

Voltage for AVea

3 dB Bandwidth vs Supply

for AVea

Peaking vs Supply Voltage

for AVea

3 dB Bandwidth vs Temperature

2060– 3

EL2160C

130 MHz Current Feedback Amplifier

Typical Performance Curves

Ð Contd.

for Various CL

Frequency Response

for Various CINb

Frequency Response

vs Frequency

PSRR and CMRR

Distortion vs Frequency

2nd and 3rd Harmonic

vs Frequency

Transimpedance (ROL)

vs Frequency

Voltage and Current Noise

Impedance vs Frequency

Closed-Loop Output

vs Die Temperature

Transimpedance (ROL)

2060– 4

EL2160C

130 MHz Current Feedback Amplifier

Typical Performance Curves

Ð Contd.

(4 Samples)

vs Die Temperature

Offset Voltage

vs Die Temperature

Supply Current

vs Supply Voltage

Supply Current

vs Die Temperature

aInput Resistance

vs Die Temperature

Input Current

vs Input Voltage

aInput Bias Current

vs Die Temperature

Output Voltage Swing

vs Die Temperature

Short Circuit Current

vs Die Temperature

PSRR & CMRR

2060– 5

EL2160C

130 MHz Current Feedback Amplifier

Typical Performance Curves

Ð Contd.

RLe150

vs DC Input Voltage,

Differential Gain

RLe150

vs DC Input Voltage,

Differential Phase

Pulse Response

Small Signal

RLe500

vs DC Input Voltage,

Differential Gain

RLe500

vs DC Input Voltage,

Differential Phase

Pulse Response

Large Signal

vs Supply Voltage

Slew Rate

vs Temperature

Slew Rate

vs Settling Accuracy

Settling Time

2060– 6

EL2160C

130 MHz Current Feedback Amplifier

Typical Performance Curves

Ð Contd.

Long Term Settling Error vs Ambient Temperature

Maximum Power Dissipation

8-Lead Plastic DIP

vs Ambient Temperature

Maximum Power Dissipation

8-Lead Plastic SO

2060– 7

Burn-In Circuit

EL2160C

2060– 8

EL2160C

130 MHz Current Feedback Amplifier

Differential Gain and Phase Test Circuit

2060– 9

Simplified Schematic

(One Amplifier)

2060– 10

EL2160C

130 MHz Current Feedback Amplifier

Applications Information

Product Description

The EL2160C is a current mode feedback amplifi-

er that offers wide bandwidth and good video

specifications at a moderately low supply cur-

rent. It is built using Elantec’s proprietary com-

plimentary bipolar process and is offered in in-

dustry standard pin-outs. Due to the current

feedback architecture, the EL2160C closed-loop

3 dB bandwidth is dependent on the value of the

feedback resistor. First the desired bandwidth is

selected by choosing the feedback resistor, RF,

and then the gain is set by picking the gain resis-

tor, RG. The curves at the beginning of the Typi-

cal Performance Curves section show the effect of

varying both RFand RG. The 3 dB bandwidth is

somewhat dependent on the power supply volt-

age. As the supply voltage is decreased, internal

junction capacitances increase, causing a reduc-

tion in closed loop bandwidth. To compensate for

this, smaller values of feedback resistor can be

used at lower supply voltages.

Power Supply Bypassing and Printed

Circuit Board Layout

As with any high frequency device, good printed

circuit board layout is necessary for optimum

performance. Ground plane construction is high-

ly recommended. Lead lengths should be as short

as possible, below (/4×. The power supply pins

must be well bypassed to reduce the risk of oscil-

lation. A 1.0 mF tantalum capacitor in parallel

with a 0.01 mF ceramic capacitor is adequate for

each supply pin.

For good AC performance, parasitic capacitances

should be kept to a minimum, especially at the

inverting input (see Capacitance at the Inverting

Input section). This implies keeping the ground

plane away from this pin. Carbon resistors are

acceptable, while use of wire-wound resistors

should not be used because of their parasitic in-

ductance. Similarly, capacitors should be low in-

ductance for best performance. Use of sockets,

particularly for the SO package, should be avoid-

ed. Sockets add parasitic inductance and capaci-

tance which will result in peaking and overshoot.

Capacitance at the Inverting Input

Due to the topology of the current feedback am-

plifier, stray capacitance at the inverting input

will affect the AC and transient performance of

the EL2160C when operating in the non-

inverting configuration. The characteristic curve

of gain vs. frequency with variations of CINb

emphasizes this effect. The curve illustrates how

the bandwidth can be extended to beyond

200 MHz with some additional peaking with an

additional 2 pF of capacitance at the VINbpin

for the case of AVea

2. Higher values of capac-

itance will be required to obtain similar effects at

higher gains.

In the inverting gain mode, added capacitance at

the inverting input has little effect since this

point is at a virtual ground and stray capacitance

is therefore not ‘‘seen’’ by the amplifier.

Feedback Resistor Values

The EL2160C has been designed and specified

with RFe560Xfor AVea

2. This value of

feedback resistor yields extremely flat frequency

response with little to no peaking out to

130 MHz. As is the case with all current feedback

amplifiers, wider bandwidth, at the expense of

slight peaking, can be obtained by reducing the

value of the feedback resistor. Inversely, larger

values of feedback resistor will cause rolloff to

occur at a lower frequency. By reducing RFto

430X, bandwidth can be extended to 170 MHz

with under 1 dB of peaking. Further reduction of

RFto 360Xincreases the bandwidth to 195 MHz

with about 2.5 dB of peaking. See the curves in

the Typical Performance Curves section which

show 3 dB bandwidth and peaking vs. frequency

for various feedback resistors and various supply

voltages.

Bandwidth vs Temperature

Whereas many amplifier’s supply current and

consequently 3 dB bandwidth drop off at high

temperature, the EL2160C was designed to have

little supply current variations with temperature.

An immediate benefit from this is that the 3 dB

bandwidth does not drop off drastically with

temperature. With VSeg15V and AVea

the bandwidth only varies from 150 MHz to

110 MHz over the entire die junction tempera-

ture range of 0§CkTk150§C.

EL2160C

130 MHz Current Feedback Amplifier

Applications Information

Ð Contd.

Supply Voltage Range

The EL2160C has been designed to operate with

supply voltages from g2V to g15V. Optimum

bandwidth, slew rate, and video characteristics

are obtained at higher supply voltages. However,

at g2V supplies, the 3 dB bandwidth at AVe

a2 is a respectable 70 MHz. The following figure

is an oscilloscope plot of the EL2160C at g2V

supplies, AVea

2, RFeRGe560X, driving a

load of 150X, showing a clean g600 mV signal at

the output.

2060– 11

If a single supply is desired, values from a4V to

a30V can be used as long as the input common

mode range is not exceeded. When using a single

supply, be sure to either 1) DC bias the inputs at

an appropriate common mode voltage and AC

couple the signal, or 2) ensure the driving signal

is within the common mode range of the

EL2160C.

Settling Characteristics

The EL2160C offers superb settling characteris-

tics to 0.1%, typically in the 35 ns to 40 ns range.

There are no aberrations created from the input

stage which often cause longer settling times in

other current feedback amplifiers. The EL2160C

is not slew rate limited, therefore any size step up

to g10V gives approximately the same settling

time.

As can be seen from the Long Term Settling Er-

ror curve, for AVea

1, there is approximately a

0.035% residual which tails away to 0.01% in

about 40 ms. This is a thermal settling error

caused by a power dissipation differential (before

and after the voltage step). For AVeb

1, due to

the inverting mode configuration, this tail does

not appear since the input stage does not experi-

ence the large voltage change as in the non-

inverting mode. With AVeb

1, 0.01% settling

time is slightly greater than 100 ns.

Power Dissipation

The EL2160C amplifier combines both high

speed and large output current drive capability at

a moderate supply current in very small pack-

ages. It is possible to exceed the maximum junc-

tion temperature allowed under certain supply

voltage, temperature, and loading conditions. To

ensure that the EL2160C remains within its abso-

lute maximum ratings, the following discussion

will help to avoid exceeding the maximum junc-

tion temperature.

The maximum power dissipation allowed in a

package is determined by its thermal resistance

and the amount of temperature rise according to

PDMAX eTJMAX bTAMAX

iJA

The maximum power dissipation actually pro-

duced by an IC is the total quiescent supply cur-

rent times the total power supply voltage plus

the power in the IC due to the load, or

PDMAX e2*VS*ISa(VSbVOUT)*VOUT

where ISis the supply current. (To be more accu-

rate, the quiescent supply current flowing in the

output driver transistor should be subtracted

from the first term because, under loading and

due to the class AB nature of the output stage,

the output driver current is now included in the

second term.)

In general, an amplifier’s AC performance de-

grades at higher operating temperature and lower

supply current. Unlike some amplifiers, the

EL2160C maintains almost constant supply

EL2160C

130 MHz Current Feedback Amplifier

Applications Information

Ð Contd.

current over temperature so that AC perform-

ance is not degraded as much over the entire op-

erating temperature range. Of course, this in-

crease in performance doesn’t come for free.

Since the current has increased, supply voltages

must be limited so that maximum power ratings

are not exceeded.

The EL2160C consumes typically 8.5 mA and

maximum 11.0 mA. The worst case power in an

IC occurs when the output voltage is at half sup-

ply, if it can go that far, or its maximum values if

it cannot reach half supply. If we set the two

PDMAX equations equal to each other, and solve

for VS, we can get a family of curves for various

loads and output voltages according to:

VSe

RL*(TJMAX bTAMAX)

iJA

a(VOUT)2

(2 *IS*RL)aVOUT

The following curves show supply voltage (gVS)

vs RLOAD for various output voltage swings for

the 2 different packages. The curves assume

worst case conditions of TAea

85§C and ISe

11 mA.

Various VOUT (SO Package)

Supply Voltage vs RLOAD for

2060– 12

Supply Voltage vs RLOAD for

Various VOUT (PDIP Package)

2060– 13

The curves do not include heat removal or forc-

ing air, or the simple fact that the package will

probably be attached to a circuit board, which

can also provide some form of heat removal.

Larger temperature and voltage ranges are possi-

ble with heat removal and forcing air past the

part.

Current Limit

The EL2160C has an internal current limit that

protects the circuit in the event of the output be-

ing shorted to ground. This limit is set at 100 mA

nominally and reduces with junction tempera-

ture. At a junction temperature of 150§C, the cur-

rent limits at about 65 mA. If the output is short-

ed to ground, the power dissipation could be well

over 1W. Heat removal is required in order for

the EL2160C to survive an indefinite short.

Driving Cables and Capacitive Loads

When used as a cable driver, double termination

is always recommended for reflection-free per-

formance. For those applications, the back termi-

nation series resistor will decouple the EL2160C

from the capacitive cable and allow extensive ca-

pacitive drive. However, other applications may

have high capacitive loads without termination

resistors. In these applications, an additional

small value (5X–50X) resistor in series with the

output will eliminate most peaking. The gain re-

sistor, RG, can be chosen to make up for the gain

loss created by this additional series resistor at

the output.

EL2160C

130 MHz Current Feedback Amplifier

EL2160C Macromodel

*Revision A, November 1993

*AC Characteristics used CINb(pin 2) e1 pF; RFe560X

*Connections: ainput

binput

Vsupply

lll

Vsupply

llll

output

lllll

.subckt EL2160C/EL 3 2 7 4 6

*Input Stage

e1100301.0

vis 10 9 0V

h2 9 12 vxx 1.0

r1211130

l1 11 12 25nH

iinp 3 0 0.5mA

iinm205mA

r12 3 0 2Meg

*Slew Rate Limiting

h1 13 0 vis 600

r2 13 14 1K

d1 14 0 dclamp

d2 0 14 dclamp

*High Frequency Pole

*e2 30 0 14 0 0.00166666666

l3 30 17 0.43mH

c5 17 0 0.27pF

r5 17 0 500

*Transimpedance Stage

g10181701.0

ro1 18 0 2Meg

cdp 18 0 2.285pF

*Output Stage

q141819qp

q271820qn

q371921qn

q442022qp

r7 21 6 4

r8 22 6 4

ios1 7 19 2mA

ios2 20 4 2mA

*Supply Current

ips 7 4 3mA

*Error Terms

ivos 0 23 2mA

vxx 23 0 0V

e4240301.0

e5250701.0

e6260401.0

r9 24 23 562

r10 25 23 1K

r11 26 23 1K

*Models

.model qn npn (ise5eb15 bfe100 tfe0.1ns)

.model qp pnp (ise5eb15 bfe100 tfe0.1ns)

.model dclamp d (ise1eb30 ibve0.266 bve2.24 ne4)

.ends

TABWIDE

TDis6.5in TDis2.6in

EL2160CDecember 1995 Rev B

EL2160C

130 MHz Current Feedback Amplifier

EL2160C Macromodel

Ð Contd.

2060– 14

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.

Elantec, Inc.

1996 Tarob Court

Milpitas, CA 95035

Telephone: (408) 945-1323

(800) 333-6314

Fax: (408) 945-9305

European Office: 44-71-482-4596

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consent of Elantec, Inc. Life Support systems are equipment in-

tended to support 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

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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 replace-

ment of defective components and does not cover injury to per-

sons or property or other consequential damages.

Printed in U.S.A.16