1
®
FN7051
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
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EL2160
180MHz Current Feedback Amplifier
The EL2160 is a current feedback
operational amplifier with -3dB
bandwidth of 130MHz at a gain of +2.
Built using the Elantec proprietary monolithic
complementary bipolar process, this amplifier uses current
mode feedback to achieve more bandwidth at a given gain
than a conventional voltage feedback operational amplifier.
The EL2160 is designed to drive a double terminated 75Ω
coax cable to video levels. Differential gain and phase are
excellent when driving both loads of 500Ω (<0.01%/<0.01°)
and double terminated 75Ω cables (0.025%/0.1°).
The amplifier can operate on any supply voltage from 4V
(±2V) to 33V (±16.5V), yet consume only 8.5mA at any sup-
ply voltage. Using industry-standard pinouts, the EL2160 is
av ailable in 8-pin PDIP and SO packages , as well as a 16-pin
SO (0.300”) package. All are specified for operation over the
full -40°C to +85°C temperature range. For dual and quad
applications, please see the EL2260/EL2460 datasheet.
Pinouts
Features
• 130MHz 3dB bandwi d th (AV=+2)
• 180MHz 3dB bandwi d th (AV=+1)
• 0.01% differential gain, RL=500Ω
• 0.01° differential phase, RL=500Ω
• Low supply current, 8.5mA
• Wide supply range, ±2V to ±15V
• 80mA output current (peak)
• Low cost
• 1500V/µs slew rate
• Input common mode range to within 1.5V of supplies
• 35ns settling time to 0.1%
Applications
• Video amplifiers
• Cable drivers
• RGB amplifiers
• Test equipment amplifiers
• Current to voltage converters
Ordering Information
PART NUMBER PACKAGE TAPE &
REEL PKG. NO.
EL2160CN 8-Pin PDIP - MDP0031
EL2160CS-T7 8-Pin SO 7” MDP0027
EL2160CS-T13 8-Pin SO 13” MDP0027
EL2160CM 16-Pin SO (0.300”) - MDP0027
EL2160CM-T13 16-Pin SO (0.300”) 13” MDP0027
1
2
3
4
8
7
6
5
1
2
3
4
16
15
14
13
5
6
7
12
11
10
8 9
EL2160
(8-PIN PDIP, SO)
TOP VIEW
EL2160
[16-PIN SO (0.300”)]
TOP VIEW
NC
VS+
OUT
NC
NC
NC
VS+
NC
OUT
NC
NC
NC
NC
-IN
+IN
VS-
NC
NC
-IN
NC
+IN
NC
VS-
NC
-
+
-
+
Data Sheet September 26, 2001
2
NOTES:
1. Measured from TMIN to TMAX
2. VCM = ±10V for VS = ±15V and TA = 25°C, VCM = ±3V for VS = ±5V and TA = 25°C
3. The supplies are moved from ±2.5V to ±15V
4. VOUT = ±7V for VS = ±15V, and VOUT = ±2V for VS = ±5V
5. A heat sink is required to keep junction temperature below absolute maximum when an output is shorted
Absolute Maximum Rati ngs (TA = 25°C)
Voltage between VS+ and VS-. . . . . . . . . . . . . . . . . . . . . . . . . .+33V
Voltage between +IN and -IN. . . . . . . . . . . . . . . . . . . . . . . . . . . .±6V
Current into +IN or -IN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10mA
Internal Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . See Curves
Operating Ambient Temperature Range . . . . . . . . . .-40°C to +85°C
Operating Junction Temperature
Plastic Packages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150°C
Output Current. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±50mA
Storage Temperature Range . . . . . . . . . . . . . . . . . .-65°C to +150°C
CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause per manent damage to the device. This is a stress only rating and operation of the
device at these or any other conditi ons above those indicated in the operational sections of this specification is not implied.
IMPORTANT NOTE: All parameters having Min/Max specifications are guaranteed. Typical values are for information pur poses only. Unless otherwise noted, all tests
are at the specified temperature and are pulsed tests, therefore: TJ = TC = TA
Open-Loop DC Electrical Specifications VS = ±15V, R L = 150Ω, TA = 25°C unless otherwise specified.
PARAMETER DESCRIPTION CONDITIONS TEMP
LIMITS
UNITMIN TYP MAX
VOS Input Offset Voltage VS = ±5V, ±15V 25°C 2 10 mV
TC VOS Average Offset Voltage Drift (Note 1) Full 10 µV/°C
+IIN +Input Current VS = ±5V, ±15V 25°C 0.5 5 µA
-IIN -Input Current VS = ±5V, ±15V 25°C 5 25 µA
CMRR Common Mode Rejection Ratio (Note 2) VS = ±5V, ±15V 25°C 50 55 dB
-ICMR -Input Current Common Mode Rejection (Note 2) VS = ±5V, ±15V 25°C 0.2 5 µA/V
PSRR Power Supply Rejection Ratio (Note 3) 25°C 75 95 dB
-IPSR -Input Current Power Supply Rejection (Note 3) 25°C 0.2 5 µA/V
ROL Transimpedance (Note 4) VS = ±15V
RL = 400Ω
25°C 500 2000 kΩ
VS = ±5V
RL = 150Ω
25°C 500 1800 kΩ
+RIN +Input Resistance 25°C 1.5 3.0 MΩ
+CIN +Input Capacitance 25°C 2.5 pF
CMIR Common Mode Input Range VS = ±15V 25°C ±13.5 V
VS = ±5V 25°C ±3.5 V
VOOutput Voltage Swing RL = 400Ω
VS =±15V 25°C ±12 ±13.5 V
RL = 150Ω
VS =±15V 25°C ±12 V
RL = 150Ω
VS =±5V 25°C ±3.0 ±3.7 V
ISC Output Short Circuit Current (Note 5) VS = ±5V, 25°C 60 100 150 mA
VS = ±15V
ISSupply Current VS = ±15V 25°C 8.5 12.0 mA
VS = ±5V 25°C 6.4 9.5 mA
EL2160
3
NOTES:
1. All AC tests are performed on a “warmed up” part, except for Slew Rate, which is pulse tested
2. Slew Rate is with VOUT from +10V to -10V and measured at the 25% and 75% points
3. DC offset from -0.714V through +0.714V, AC amplitude 286mVP-P, f = 3.58MHz
Closed-Loop AC Electrical Specifications VS = ±15V, AV = +2, RF = 560Ω, RL = 150Ω, TA = 25°C unless otherwise noted.
PARAMETER DESCRIPTION CONDITIONS
LIMITS
UNITMIN TYP MAX
BW -3dB Bandwidth (Note 1) VS = ±15V, AV = +2 130 MHz
VS = ±15V, AV = +1 180 MHz
VS = ±5V, AV = +2 100 MHz
VS = ±5V, AV = +1 110 MHz
SR Slew Rate (Note 1)(Note 2) RL = 400Ω1000 1500 V/µs
RF = 1kΩ, RG = 110Ω
RL = 400Ω
1500 V/µs
tR, tFRise Time, Fall Time (Note 1) VOUT = ±500mV 2.7 ns
tPD Propagation Delay (Note 1) 3.2 ns
OS Overshoot (Note 1) VOUT = ±500mV 0 %
tS0.1% Settling Time (Note 1) VOUT = ±10V
AV = -1, RL = 1k 35 ns
dG Differential Gain (Note 1)(Note 3) RL = 150Ω0.025 %
RL = 500Ω0.006 %
dP Differential Phase (Note 1)(Note 3) RL = 150Ω0.1 °
RL = 500Ω0.005 °
EL2160
4
Typical Performance Curves
Non-Inverting Frequency
Response (Gain) Non-Inverting Frequency
Response (Phase) Frequency Response
for Various RL
Inverting Frequency
Response (Gain) Inverting Frequency
Response (Phase) F requency Response for
Various RF and RG
3dB Bandwidth vs
Temperature for AV = - 1
Peaking vs Supply Voltage
for AV = -1
3dB Bandwidth vs Supply
Voltage for AV = -1
R
EL2160
5
Typical Performance Curves (Continued)
3dB Bandwidth vs Supply
Voltage for AV = +1 Peaking vs Supply Voltage
for AV = +1 3dB Bandwidth vs Temper ature
for AV = +1
3dB Bandwidth vs Temper ature
for AV = +2
Peaking vs Supply Voltage
for AV = +2
3dB Bandwidth vs Supply
Voltage for AV = +2
3dB Bandwidth vs Supply
Voltage for AV = +10 Peaking vs Supply Voltage
for AV = +10 3dB Bandwidth vs Temperature
for AV = +10
EL2160
6
Typical Performance Curves (Continued)
Frequency Response
for Various CLFrequency Response
for Various CIN- PSRR and CMRR
vs Frequency
2nd and 3rd Harmonic
Distortion vs Frequency Transimpedance (R OL)
vs Frequency Voltage and Current Noise
vs Frequency
Closed-Loop Output
Impedance vs Frequency Transimpedance (ROL)
vs Die Temperature
EL2160
7
Typical Performance Curves (Continued)
Offset Voltage
vs Die Temperature
(4 Samples) Supply Current
vs Die Temperature Supply Current
vs Supply Voltage
+Input Resistance
vs Die Temperature Input Current
vs Die Temperature +Input Bias Current
vs Input Voltage
Output Voltage Swing
vs Die Temperature Short Circuit Current
vs Die Temperature PSRR & CMRR
vs Die Temperature
EL2160
8
Typical Performance Curves (Continued)
Differential Gain
vs DC Input Voltage,
RL = 150
Differential Phase
vs DC Input Voltage,
RL = 150 Small Signal
Pulse Response
Differential Gain
vs DC Input Voltage,
RL = 500
Differential Phase
vs DC Input Voltage,
RL = 500 Large Signal
Pulse Response
Slew Rat e
vs Supply Voltage Slew Rate
vs Temperature Settling Time
vs Settling Accuracy
EL2160
9
Typical Performance Curves (Continued)
Burn-In Circuit
Long Term Settling Error
0 25507510012515085
Ambient Temperature (°C)
1.6
1.4
1
0.8
0.6
0.4
0.2
0
1.2
Power Dissipation (W)
Package Power Dissipation vs Ambient Temp.
JEDEC JESD51-3 Low Effective Thermal Conductivity Test
Board
SO16 (0.300”)
θJA=93°C/W
SO8
θJA=160°C/W
PDIP8
θJA=100°C/W
781mW
1.250W
1.344W
EL2160
EL2160
10
Differential Gain and Phase Test Circuit
Simplified Schematic (One Amplifier)
Applications Information
Product Description
The EL2160 is a current mode feedback amplifier that off ers
wide bandwidth and good video specifications at a
moderately low supply current. It is built using Elantec's
proprietary complimentar y bipolar process and is offered in
industry standard pin-outs. Due to the current feedback
architecture, the EL2160 closed-loop 3dB 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
resistor, RG. The curves at the beginning of the Typical
Performance Curves section show the effect of varying both
RF and RG. The 3dB bandwidth is somewhat dependent on
the power supply voltage. As the supply voltage is
decreased, internal junction capacitances increase, causing
a reduction in closed loop bandwidth. To compensate for
this, smaller values of f eedback resistor can be used at lower
supply voltages.
EL2160
11
Power Supply Bypassing and Printed Circuit
Board Layout
As with any high frequency de vice, good printed circuit board
layout is necessary for optimum performance. Ground plane
construction is highly recommended. Lead lengths should be
as short as possible, below ¼”. The power supply pins must
be well bypassed to reduce the risk of oscillation. A 1.0µF
tantalum capacitor in parallel with a 0.01µF ceramic
capacitor is adequate for each supply pin.
F or 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 indu ctance.
Similarly, capacitors should be low inductance for best
perf ormance. Use of sockets, particularly for the SO
package, should be avoided. Sockets add parasitic
inductance and capacitance which will result in peaking and
overshoot.
Capacitance at the Inverting Input
Due to the topology of the current feedback amplifier, stray
capacitance at the inverting input will affect the AC and
transient performance of the EL2160 when operating in the
non-inverting configuration. The characteristic curve of gain
vs. frequency with variations of CIN- emphasizes this effect.
The curve illustrates how the bandwidth can be extended to
beyo nd 200MHz with some addition al peaking with an
additional 2pF of capacitance at the VIN- pin for the case of
AV= +2. Higher values of capacitance 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 EL2160 has been designed and specified with
RF= 560Ω for A V= +2. This value of f eedback resistor yields
extremely flat frequency response with little to no peaking
out to 130MHz. 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 feedb ack resistor will
cause rolloff to occur at a lower frequency. By reducing RF to
430Ω, bandwidth can be extended to 170MHz with under
1dB of peaking. Further reduction of RF to 360Ω increases
the bandwidth to 195MHz with about 2.5dB of peaking. See
the curves in the Typical Performance Curves section which
show 3dB bandwidth and peaking vs. frequency for various
feedback resistors and various supply voltages.
Bandwidth vs Temperature
Whereas many amplifier's supply current and consequently
3dB bandwidth drop off at high temperature, the EL2160 was
designed to have little supply current variations with
temperature. An immediate benefit from this is that the 3dB
bandwidth does not drop off drastically with temperature.
With VS= ±15V and A V= +2, the bandwidth only varies from
150MHz to 110MHz ov er the entire die junction temperature
range of 0°C < T < 150°C.
Supply Voltage Range
The EL2160 has been designed to ope rate with supply
voltages from ±2V to ±15V. Optimum bandwidth, slew rate,
and video characteristics are obtained at high er supply
voltages. However, at ±2V supplies, the 3dB bandwidth at
AV= +2 is a respectable 70MHz. The follo wing figure is an
oscilloscope plot of the EL2160 at ±2V supplies, AV=+2,
RF=R
G=560Ω, driving a load of 150Ω, showing a clean
±600mV signal at the output.
If a single supply is desired, values from +4V to +30V can be
used as long as the input common mode range i s not
exceeded. When using a single supply, be sure to either 1)
DC bias the inputs at an appropr iate common mode voltage
and AC couple the signal, or 2) ensure the driving signal is
within the common mode range of the EL2160.
Settling Characteristics
The EL2160 offers superb settling characteristics to 0.1%,
typically in the 35ns to 40ns range. There are no aberrations
created from the input stage which often cause longer
settling times in other current feedback amplifie rs. The
EL2160 is not slew rate limited, theref ore any siz e step up to
±10V gives approximately the same settling time.
As can be seen from the Long Term Settling Error curve, for
AV= +1, there is approximately a 0.035% residual which
tails away to 0.01% in about 40µs. This is a thermal settling
error caused by a power dissipation differential (before and
after the voltage step). For AV= -1, due to the inverting
mode configuration, this tail does not appear since the input
stage does not experience the large voltage change as in the
non-inverting mode. With AV= -1, 0.01% settling time is
slightly greater than 100ns.
EL2160
12
Power Dissipation
The EL2160 amplifier combines both high speed and large
output current drive capability at a moderate supply current
in very small packages. It is possible to e xceed the maximum
junction temperature allowed under certain supply voltage,
temperature, and loading conditions. To ensure that the
EL2160 remains within its absolute maximum ratings, the
following discussion will help to avoid exceeding the
maximum junction temperatur e.
The maximum power dissipation allowed in a package is
determined by its thermal resistance and the amount of
temperature rise according to:
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 load, or:
where IS is the supply current. (To be more accurate, 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 degrades at
higher operating temperature and lower supply current.
Unlike some amplifiers, the EL2160 maintains almost
constant supply current over temperature so that AC
perfor m ance is not degraded as much over the entire
operating temperature range. Of course, this increase in
perf ormance doesn't come f or free. Since the current has
increased, supply voltages must be limited so that maximum
power r atings are not exceeded.
The EL2160 consumes typically 8.5mA and maximum
11.0mA. The worst case power in an IC occurs when the
output voltage is at half supply, 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:
The following curves show supply voltage (±VS) vs RLOAD
for various output voltage swings for the 2 different
packages. The curves assume worst case conditions of
TA= +85°C and IS= 11mA.
The curves do not include heat removal or forcing 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. La rger temperature and voltage ranges are
possible with heat removal and forcing air past the part.
Current Limit
The EL2160 has an internal current limit that protects the
circuit in the event of the output being shorted to ground.
This limit is set at 100mA nominally and reduces with
junction temperature. At a junction temperature of 150°C , the
current limits at about 65mA. If the output is shorted to
ground, the power dissipation could be well over 1W. Heat
removal is required in order f or the EL2160 to survive an
indefinite short.
Driving Cables and Capacit ive Loads
When used as a cable driver, double termination is always
recommended for reflection-free perf ormance. For those
applications, the back termination series resistor will
decouple the EL2160 from the capacitive cable and allow
extensive capacitive drive. However, other applications may
have high capacitive loads without termination resistors. In
these applications, an additional small value (5Ω–50Ω)
resistor in series with the output will eliminate most peaking.
PDMAX TJMAX TAMAX
–
θJA
---------------------------------------------=
PDMAX 2V
SV(SVOUT)VOUT
RL
----------------
×–+×=
VSRLTMAX-TAMAX
()×
θJA
--------------------------------------------------------- VOUT
()2(ISRL)VOUT
+××[]÷+=
Supply Voltage vs RLOAD for
Various VOUT (8-Pin SO Package)
Supply Voltage vs RLOAD for
Various VOUT (PDIP Package)
EL2160
13
The gain resistor , RG, can be chosen to make up for the gain
loss created by this additional series resistor at the output.
EL2160 Macromodel
* Revision A, November 1993
* AC Characteristics used CIN- (pin 2) = 1 pF; RF = 560Ω
* Connections: +input
* | -input
* | | +Vsupply
* | | | -Vsupply
* | | | | output
* | | | | |
.subckt EL2160/EL 3 2 7 4 6
*
* Input Stage
*
e1 10 0 3 0 1.0
vis 10 9 0V
h2 9 12 vxx 1.0
r1 2 11 130
l1 11 12 25nH
iinp 3 0 0.5µA
iinm 2 0 5µA
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 0.43µH
c5 17 0 0.27pF
r5 17 0 500
*
* Transimpedance Stage
*
g1 0 18 17 0 1.0
ro1 18 0 2Meg
cdp 18 0 2.285pF
*
* Output Stage
*
q1 4 18 19 qp
q2 7 18 20 qn
q3 7 19 21 qn
q4 4 20 22 qp
r7 21 6 4
r8 22 6 4
ios1 7 19 2mA
ios2 20 4 2mA
*
* Supply Current
*
ips 7 4 3mA
*
EL2160
14
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Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quali ty
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notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and
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For information regarding Intersil Corporati on and its products, see www.intersil.com
* Error Terms
*
ivos 0 23 2mA
vxx 23 0 0V
e4 24 0 3 0 1.0
e5 25 0 7 0 1.0
e6 26 0 4 0 1.0
r9 24 23 562
r10 25 23 1K
r11 26 23 1K
*
* Models
*
.model qn npn (is=5e-15 bf=100 tf=0.1ns)
.model qp pnp (is=5e-15 bf=100 tf=0.1ns)
.model dclamp d (is=1e-30 ibv=0.266 bv=2.24 n=4)
.ends
EL2160
