ELANTEC EL2005CG

High Accuracy Fast Buffer
Features
General Description
# Low input currentÐ50 pA
# Low offset and driftÐ
2 mV/25 mV/§ C
# High slew rateÐ1500 V/ms
# Fast rise and fall timeÐ2.5 ns
# High input resistanceÐ1000 GX
# BandwidthÐ140 MHz
# Pin compatible with ELH0033
# MIL-STD-883 Revision C devices
manufactured in U.S.A.
The EL2005 is a high-speed, FET input buffer similar to
ELH0033 and EL2004 but with input specifications significantly improved over the previous types. The input stage employs a
cascode configuration to maintain constant input characteristics over the full g 10V input range. The input looks like a 3 pF
capacitor to ground in almost all cases since the DC bias current
is constant with input voltage. In sample and hold circuits this
results in an order of magnitude improvement in hold characteristics. Input offset voltage and offset voltage drift are also
improved a factor of two over previous types.
Advantages
# No input loading
# Input current independent of
input voltage
# Eliminates offset adjustments
# Drives cables directly
Ordering Information
Part No.
Temp. Range
Package OutlineÝ
EL2005CG
b 25§ C to a 85§ C
TO-8
MDP0002
EL2005G
b 55§ C to a 125§ C
TO-8
MDP0002
EL2005G/883B b 55§ C to a 125§ C
TO-8
MDP0002
EL2005/EL2005C
EL2005/EL2005C
These excellent DC characteristics are complemented by a wide
140 MHz bandwidth while the 1500 V/ms slew rate and excellent phase linearity of the ELH0033 family are preserved allowing direct plug-in replacement for upgraded performance. (For
even faster operation see EL2004.)
Elantec facilities comply with MIL-I-45208A and are MILSTD-1772 certified. Elantec’s Military devices comply with
MIL-STD-883B Revision C and are manufactured in our rigidly
controlled, ultra-clean facilities in Milpitas, California. For additional information on Elantec’s Quality and Reliability Assurance Policy and procedures request brochure QRA-1.
Simplified Schematic
Connection Diagram
Note: Case is electrically isolated.
2005 – 2
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. Patent pending.
CMSÝ2005DS
© 1989 Elantec, Inc.
January 1990 Rev F
2005 – 1
Top View
EL2005/EL2005C
High Accuracy Fast Buffer
Absolute Maximum Ratings (TA e 25§ C)
Supply Voltage (V a b Vb)
Input Voltage
Power Dissipation (See curves)
Continuous Output Current
Peak Output Current
VS
VIN
PD
IOC
IOP
TA
40V
40V
1.5W
g 100 mA
g 250 mA
TJ
TST
Operating Temperature Range
EL2005
EL2005C
Operating Junction Temperature
Storage Temperature
Lead Temperature
(Soldering, 10 seconds)
b 55§ C to a 125§ C
b 25§ C to a 85§ C
175§ C
b 65§ C to a 150§ C
300§ 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 TJ e TC e TA.
Test Level
I
II
III
IV
V
Test Procedure
100% production tested and QA sample tested per QA test plan QCX0002.
100% production tested at TA e 25§ C and QA sample tested at TA e 25§ C ,
TMAX and TMIN per QA test plan QCX0002.
QA sample tested per QA test plan QCX0002.
Parameter is guaranteed (but not tested) by Design and Characterization Data.
Parameter is typical value at TA e 25§ C for information purposes only.
DC Electrical Characteristics VS e g 15V, VIN e 0V, TMIN s TA s TMAX
Description
Test Conditions
Min
RS s 100 kX, TJ e 25§ C
(Note 1)
VOS
Output Offset
Voltage
DVOS/DT
Average Temperature
Coefficient of
RS e 100X
Offset Voltage
2
RS s 100 kX
PSRR
Supply Rejection
IB
Input Bias Current
AV
RIN
Voltage Gain
Input Impedance
g 10V s VS s g 20V
65
Output
Impedance
5
I
10
I
25
V
75
I
Min
Typ Max
3
60
Test Units
Level
10
I
mV
15
III
mV
25
V
mV/§ C
75
II
dB
TJ e 25§ C (Notes 1 and 3)
2
50
I
5
100
I
pA
TA e 25§ C (Notes 2 and 3)
50
500
IV
100
1000
IV
pA
TJ e TA e TMAX
2
5
I
0.5
5
III
nA
RS e 100X, RL e 1 kX,
VIN e g 10V
0.97
0.98
1.0
I
0.96
0.98
1.0
II
V/V
RS e 100X, RL e 100X,
vIN e g 10V
0.88
0.95
0.98
I
0.88
0.95
0.99
II
V/V
IV
X
I
X
II
X
RL e 1 kX,
b 10V s VIN s g 10V
2 c 109 1012
TJ e 25§ C (Note 1),
RL e 1 kX
RO
EL2005C
Test
Typ Max
Level
1010
RL e 1 kX,
VIN e g 1V
1012
4
2
I
I
8
I
2 c 109 1012
1010
1012
4
9
TD is 3.8in
EL2005
Parameter
EL2005/EL2005C
High Accuracy Fast Buffer
DC Electrical Characteristics VS e g 15V, VIN e 0V, TMIN s TA s TMAX Ð Contd.
Description
Min
VO
Output Voltage
Swing
EL2005C
Test Conditions
VIN e g 14V,
RL e 1 kX
VIN e g 10.5V, RL e 100X,
TA e 25§ C
Typ
Max
Test
Min
Level
g 12.5
V
g 9.8
I
g9
g9
Typ
Max
Test Units
Level
g 12.5
V
V
g 9.8
I
V
IS
Supply Current VIN e 0 (Note 1)
19
22
I
19
24
II
mA
PD
Power
Consumption
570
660
I
570
720
II
mW
VIN e 0
TD is 1.7in
EL2005
Parameter
AC Electrical Characteristics TC e 25§ C, VS e g 15V, RS e 50X, RL e 1 kX
Description
Test Conditions
EL2005C
Test
Test
Min Typ Max
Min Typ Max
Level
Level
Units
SR
Slew Rate
VIN e g 10V, VOUT e g 5V 1000 1500
III
1000 1500
III
V/ms
BW
Bandwidth
VIN e 1 Vrms
140
V
140
V
MHz
wNL
Phase
Non-Linearity
BW e 1 MHz to 20 MHz
2
V
2
V
Degree
tr
Rise Time
DVIN e 0.5V
2.5
V
2.5
V
ns
tP
Propagation Delay DVIN e 0.5V
1.0
V
1.0
V
ns
HD
Harmonic
Distortion
f l1 kHz
k 0.1
V
k 0.1
V
%
AV
Voltage Gain
RS e 100X, VIN e 1 Vrms,
f e 1 kHz
RO
Output Impedance VIN e 1 Vrms,
f e 1 kHz
0.97
0.99
1.0
I
4
8
I
0.96
0.99
1.0
II
V/V
4
9
II
X
Note 1: Specification is at 25§ C junction temperature due to requirements of high-speed automatic testing. Actual values at operating
temperatures will exceed the value at TJ e 25§ C. When supply voltages are g 15V, no-load operating junction temperatures
may rise 40§ C to 60§ C above ambient and more under load conditions. Accordingly, VOS may change one to several mV, and
IB will change significantly during warm-up. Refer to IB vs Temperature graph for expected values.
Note 2: Measured in still air seven minutes after application of power.
Note 3: Input bias current is guaranteed over the input range of b10V s VIN s a 10V.
3
TD is 2.5in
EL2005
Parameter
EL2005/EL2005C
High Accuracy Fast Buffer
Typical Performance Curves
Maximum Power
Dissipation
Gain vs Input Voltage
Output Resistance vs
Output Current
Frequency Response
Supply Current vs
Supply Voltage
Offset Voltage vs
Supply Voltage
Input Bias Current vs
Input Voltage
Input Bias Current vs
Temperature
Input Bias Current
During Warm-up
Rise Time vs
Temperature
Small Signal Pulse
Response
Large Signal Pulse
Response
2005 – 3
2005 – 4
4
EL2005/EL2005C
High Accuracy Fast Buffer
Typical Applications
Using Resistor
Current Limiting
Offset Zero Adjust
Current Limiting
Using Current Sources
2005 – 5
2005 – 6
2005 – 7
Q1 e Q2 e 2N2905
Q3 e Q4 e 2N2219
High Input Impedance
AC Coupled Amplifier
Coaxial Cable Driver
*Select C1 for optimum pulse response
2005 – 8
5
2005 – 9
EL2005/EL2005C
High Accuracy Fast Buffer
Typical Applications Ð Contd.
50X Cable Driver with
Short Circuit Protection
Bootstrapped Supplies for
High Voltage Applications
NPN e 2N6551
PNP e 2N6554
( 2W devices
or equivalent
2005 – 11
2005 – 10
High-Speed Sample and Hold
2005 – 12
6
EL2005/EL2005C
High Accuracy Fast Buffer
Resistor values may be predicted by:
Applications Information
Recommended Layout Precautions
RLIM j
RF/video printed circuit board layout rules
should be followed when using the EL2005 since
it will provide power gain to frequencies over
100 MHz. Ground planes are recommended and
power supplies should be decoupled at each device with low inductance capacitors. In addition,
ground plane shielding may be extended to the
metal case of the device since it is electrically isolated from internal circuitry. Alternatively, the
case should be connected to the output to minimize input capacitance.
Va
Vb
e
ISC
ISC
where: ISC s 100 mA for EL2005
The inclusion of limiting resistors in the collectors of the output transistors reduces output voltage swing. Decoupling VC a and VC b pins with
capacitors to ground will retain full output swing
for transient pulses. An alternate active current
limit technique that retains full DC output swing
is also shown on page 4. In this circuit, the current sources are saturated during normal operation thus applying full supply voltage to the VC
pins. Under fault conditions, the voltage decreases as required by the overload.
Offset Voltage Adjustment
The EL2005’s offset voltages have been actively
trimmed by laser to meet guaranteed specifications when the offset preset pin is shorted to the
offset adjust pin. The pre-calibration allows the
devices to be used in most DC or AC applications
without individually offset nulling each device. If
offset null is desirable, it is simply obtained by
leaving the offset preset pin open and connecting
a trim pot of 200X between the offset adjust pin
and V b as illustrated on page 4.
RLIM j
VBE
0.6V
e
e 10X
ISC
60 mA
Capacitive Loading
The EL2005 is designed to drive capacitive loads
such as coaxial cables in excess of several thousand picofarads without susceptibility to oscillation. However, peak current resulting from
(C c dV/dt) should be limited below absolute
maximum peak current ratings for the devices.
Operation from Single or Asymmetrical
Power Supplies
This device type may be readily used in applications where symmetrical supplies are unavailable
or not desirable. In this case, an apparent output
offset occurs due to the device’s voltage gain of
less than unity. This additional output offset error may be predicted by:
Thus:
DVIN
c CL s IOUT s g 250 mA
Dt
(V a b V b )
e 0.005 (V a b V b )
DVO j (1 b AV)
2
In addition, power dissipation resulting from
driving capacitive loads plus standby power
should be kept below the total package power
rating:
where: AV e No load voltage gain, typically 0.99
V ae Positive supply voltage
V be Negative supply voltage
PDpkg t PDC a PAC
PDpkg t (V a b V b ) c IS a PAC
For example, with V a e a 5V and V b e
b 12V, DVO would be b 35 mV. This may be adjusted to zero as described above.
PAC j (VP-P)2 c f c CL
where: VP-P e Peak-to-peak output voltage
swing
f e Frequency
CL e Load Capacitance
Short Circuit Protection
In order to optimize transient response and output swing, output current limit has been omitted
from the EL2005. Short circuit protection may be
added by inserting appropriate value resistors between V a and VC a pins and V b and VC b pins
as shown on page 4.
7
EL2005/EL2005C
High Accuracy Fast Buffer
Hardware
Applications Information Ð Contd.
In order to utilize the full drive capabilities of the
EL2005, it should be mounted with a heatsink,
particularly for extended temperature operation.
The case is isolated from the circuit and may be
connected to system chassis.
Operation within an Op Amp Loop
The EL2005 may be used as a current booster or
isolation buffer within a closed loop with op
amps such as the ELH0032 and HA2500 and
HA2600 series. An isolation resistor of 47X
should be used between the op amp output and
the input of EL2005. The wide bandwidth and
high slew rates of the EL2005 assure that the
loop has the characteristics of the op amp and
that additional rolloff is not required.
IMPORTANT!
Power supply bypassing is necessary to prevent
oscillation with the EL2005 in all circuits. Low
inductance ceramic disc capacitors with the
shortest practical lead lengths must be connected
from each supply lead (within (/4× to (/2× of the
device package) to a ground plane. Capacitors
should be one or two 0.1 mF in parallel; adding a
4.7 mF solid tantalum capacitor will help in troublesome instances.
Burn-In Circuit
2005 – 13
8
EL2005/EL2005C
TAB WIDE
High Accuracy Fast Buffer
EL2005 Macromodel
input
l
l
l
l
l
l
Va
l
l
l
l
l
a Vc a
l
l
l
l
Vb
l
Vcb
*
l
l output
*
l
l l
.subckt M2005
5
12
1
10
9
11
* Models
.model qn npn (is e 5eb14 bf e 150 vaf e 100 rc e 1 rb e 5 re e 1 ikf e 200mA
a cje e 5pF cjc e 5pF mje e .42 mjc e .23 tf e .3nS tr e 200nS br e 5 vtf e 0)
.model qp pnp (is e 5eb14 bf e 150 vaf e 100 rc e .2 rb e 3 re e 1 ikf e 100mA
a cje e 5.7pF cjc e 4pF tf e .3nS mje e .32 mjc e .43 tr e 170nS br e 5 vtf e 0)
.model qfa njf (vto eb8V beta e 2.344eb3 cgd e 10pF cgs e 7pF lambda e 671eb6)
.model qfb njf(vto eb4V beta e 1.06eb3 cgd e 3pF cgs e 3pF)
* Resistors
r1 21 22 30
r2 7 10 30
r3 25 11 3
r4 11 26 3
* Transistors
j1a 20 5 21 qfb
j1b 28 10 27 qfb
j2 12 11 20 qfa
j4 24 10 28 qfa
q3 22 22 23 qn
q4 1 22 25 qn
q5 24 24 23 qp
q6 9 24 26 qp
q7 27 27 7 qn
.ends
9
TD is 4.1in
* Connections:
*
*
*
*
EL2005/EL2005C
High Accuracy Fast Buffer
EL2005 Macromodel Ð Contd.
2005 – 14
10
11
BLANK
EL2005/EL2005C
EL2005/EL2005C
High Accuracy Fast Buffer
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.
January 1990 Rev F
WARNING Ð 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 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
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.
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
12
Printed in U.S.A.