Maxim MAX4385EEUK-T Low-cost, 230mhz, single/quad op amps with rail-to-rail outputs and â±15kv esd protection Datasheet

19-2422; Rev 0; 4/02
Low-Cost, 230MHz, Single/Quad Op Amps with
Rail-to-Rail Outputs and ±15kV ESD Protection
The MAX4385E/MAX4386E op amps are unity-gain stable devices that combine high-speed performance,
Rail-to-Rail ® outputs, and ±15kV ESD protection.
Targeted for applications where an input or an output is
exposed to the outside world, such as video and communications, these devices are compliant with
International ESD Standards: ±15kV IEC 1000-4-2 AirGap Discharge, ±8kV IEC 1000-4-2 Contact Discharge,
and the ±15kV Human Body Model.
The MAX4385E/MAX4386E operate from a single 5V
supply with a common-mode input voltage range that
extends beyond VEE. The MAX4385E/MAX4386E consume only 5.5mA of quiescent supply current per
amplifier while achieving a 230MHz -3dB bandwidth,
30MHz 0.1dB gain flatness and a 450V/µs slew rate.
Applications
Set-Top Boxes
Surveillance Video
Systems
Battery-Powered
Instruments
Analog-to-Digital
Converter Interface
CCD Imaging
Systems
Video Routing and
Switching Systems
Digital Cameras
Video-on-Demand
Video Line Driver
Features
♦ ESD-Protected Inputs and Outputs
±15kV—Human Body Model
±8kV—IEC 1000-4-2 Contact Discharge
±15kV—IEC 1000-4-2 Air-Gap Discharge
♦ Low Cost and High Speed
230MHz -3dB Bandwidth
30MHz 0.1dB Gain Flatness
450V/µs Slew Rate
♦ Rail-to-Rail Outputs
♦ Input Common-Mode Range Extends Beyond VEE
♦ Low Differential Gain/Phase: 0.02%/0.01°
♦ Low Distortion at 5MHz
-60dBc SFDR
-58dB Total Harmonic Distortion
♦ Ultra-Small 5-Pin SOT23 and 14-Pin TSSOP
Packages
Ordering Information
PART
TEMP RANGE
PINPACKAGE
TOP
MARK
MAX4385EEUK-T
-40°C to +85°C
5 SOT23-5
ADZL
MAX4386EESD
-40°C to +85°C
14 SO
—
MAX4386EEUD
-40°C to +85°C
14 TSSOP
—
Pin Configurations
Typical Operating Circuit
5V
TOP VIEW
2.2µF
IN
OUT 1
75Ω
75Ω
5
VCC
4
IN-
OUT
Zo = 75Ω
MAX4385E
VEE 2
MAX4385E
75Ω
IN+ 3
220Ω
220Ω
SOT23
VIDEO LINE DRIVER
Pin Configurations continued at end of data sheet.
Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
MAX4385E/MAX4386E
General Description
MAX4385E/MAX4386E
Low-Cost, 230MHz, Single/Quad Op Amps with
Rail-to-Rail Outputs and ±15kV ESD Protection
ABSOLUTE MAXIMUM RATINGS
Power-Supply Voltage (VCC to VEE) .........................-0.3V to +6V
IN_+, IN_-, OUT_,.............................(VEE - 0.3V) to (VCC + 0.3V)
Output Short-Circuit Duration to
VCC or VEE.............................................................Continuous
Continuous Power Dissipation (TA = +70°C)
5-Pin SOT23 (derate 8.7mW/°C above +70°C)...........696mW
14-Pin SO (derate 8.33mW/°C above +70°C).............667mW
14-Pin TSSOP (derate 10mW/°C above +70°C) .........727mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or at any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure
to absolute maximum rating conditions for extended periods may affect device reliability.
DC ELECTRICAL CHARACTERISTICS
(VCC = 5V, VEE = 0, VCM = VCC/2, VOUT = VCC/2, RL = ∞ to VCC/2, CBYPASS = 2.2µF, TA = TMIN to TMAX, unless otherwise noted.
Typical values are at TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
Input Common-Mode Voltage
Range
VCM
Input Offset Voltage
VOS
Input Offset Voltage Matching
Input Offset Voltage Tempco
Input Bias Current
Input Offset Current
Input Resistance
CONDITIONS
MIN
VEE 0.2
Guaranteed by CMRR
TA = +25°C
0.2
TA = -40°C to +85°C
V
20
mV
1
mV
µV/°C
IB
6.5
20
0.5
7
IOS
RIN
Open-Loop Gain
kΩ
Common mode (-0.2V ≤ VCM ≤ +2.75V)
3
MΩ
95
dB
VEE - 0.2V ≤ VCM ≤ VCC - 2.25V
70
0.25V ≤ VOUT ≤ 4.75V, RL = 2kΩ
50
61
0.8V ≤ VOUT ≤ 4.5V, RL = 150Ω
48
63
RL = 150Ω
VOUT
RL = 75Ω
RL = 75Ω to
ground
ISC
Open-Loop Output Resistance
ROUT
Power-Supply Rejection Ratio
PSRR
µA
70
RL = 2kΩ
IOUT
µA
Differential mode (-1V ≤ VIN ≤ +1V)
1V ≤ VOUT ≤ 4V, RL = 50Ω
2
VCC 2.25
8
AVOL
Output Short-Circuit Current
UNITS
28
MAX4386E
CMRR
Output Current
MAX
TCVOS
Common-Mode Rejection Ratio
Output Voltage Swing
TYP
VCC - VOH
0.05
0.270
VOL - VEE
0.05
0.150
0.5
VCC - VOH
0.3
VOL - VEE
0.25
0.8
VCC - VOH
0.5
0.8
VOL - VEE
0.5
1.75
VCC - VOH
1
1.7
VOL - VEE
0.025
0.125
Sinking from RL = 50Ω to VCC
40
55
Sourcing into RL = 50Ω to VEE
25
50
±100
Sinking or sourcing
VS = 4.5V to 5.5V
dB
58
50
V
mA
8
mA
Ω
62
dB
_______________________________________________________________________________________
Low-Cost, 230MHz, Single/Quad Op Amps with
Rail-to-Rail Outputs and ±15kV ESD Protection
(VCC = 5V, VEE = 0, VCM = VCC/2, VOUT = VCC/2, RL = ∞ to VCC/2, CBYPASS = 2.2µF, TA = TMIN to TMAX, unless otherwise noted.
Typical values are at TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
Operating Supply Voltage
Range
VS
Quiescent Supply Current
(per Amplifier)
IS
CONDITIONS
Guaranteed by PSRR
MIN
4.5
5.5
MAX
UNITS
5.5
V
9
mA
±15
Human Body Model
ESD Protection Voltage
(Note 2)
TYP
IEC 1000-4-2 Contact Discharge
±8
IEC 1000-4-2 Air-Gap Discharge
±15
kV
AC ELECTRICAL CHARACTERISTICS
(VCC = 5V, VEE = 0, VCM = 1.5V, RL = 100Ω to VCC/2, VOUT = VCC/2, AVCL = 1V/V, TA = +25°C, unless otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Small-Signal -3dB Bandwidth
BWSS
VOUT = 100mVP-P
230
MHz
Large-Signal -3dB Bandwidth
BWLS
VOUT = 2VP-P
180
MHz
Small-Signal 0.1dB Gain
Flatness
BW0.1dBSS
VOUT = 100mVP-P
33
MHz
Large-Signal 0.1dB Gain
Flatness
BW0.1dBLS
VOUT = 2VP-P
30
MHz
V/µs
Slew Rate
SR
VOUT = 2V step
450
Settling Time to 0.1%
tS
VOUT = 2V step
14
ns
4
ns
-60
dBc
Rise/Fall Time
tR , tF
VOUT = 100mVP-P
Spurious-Free Dynamic Range
SFDR
fC = 5MHz, VOUT = 2VP-P
2nd harmonic
Harmonic Distortion
Two-Tone, Third-Order
Intermodulation Distortion
Channel-to-Channel Isolation
HD
IP3
CHISO
Input 1dB Compression Point
fC = 5MHz,
VOUT = 2VP-P
-70
3rd harmonic
-60
total harmonic
-58
dBc
f1 = 4.7MHz, f2 = 4.8MHz,
VOUT = 1VP-P
-60
Specified at DC
-95
dB
fC = 10MHz, AVCL = 2V/V
13
dBm
Degrees
dBc
Differential Phase Error
DP
NTSC, RL = 150Ω
0.01
Differential Gain Error
DG
NTSC, RL = 150Ω
0.02
%
Input Noise-Voltage Density
en
f = 10kHz
11.5
nV/√Hz
Input Noise-Current Density
in
f = 10kHz
2
pA/√Hz
8
pF
f = 10MHz
2.2
Ω
Input Capacitance
CIN
Output Impedance
ZOUT
Note 1: All devices are 100% production tested at TA = +25°C. Specifications over temperature limits are guaranteed by design.
Note 2: ESD protection is specified for test point A and test point B only (Figure 6).
_______________________________________________________________________________________
3
MAX4385E/MAX4386E
DC ELECTRICAL CHARACTERISTICS (continued)
Typical Operating Characteristics
(VCC = 5V, VEE = 0, VCM = 1.5V, AVCL = 1V/V, RL = 100Ω to VCC/2, TA = +25°C, unless otherwise noted.)
0
0
GAIN (dB)
1
-1
0.2
0.1
-0.2
-3
-3
-0.3
-4
-4
-0.4
-5
-5
-0.5
-0.6
-6
1M
10M
100M
100k
1G
1M
LARGE-SIGNAL GAIN FLATNESS
vs. FREQUENCY
100M
100k
1G
10M
0
-0.1
-0.2
-0.3
MAX4385E/86E toc05
0
100
10
1
-20
1G
-30
-40
-50
-60
3RD HARMONIC
-70
0.1
-0.4
VOUT = 2VP-P
AVCL = 1V/V
-10
DISTORTION (dBc)
0.1
100M
DISTORTION vs. FREQUENCY
OUTPUT IMPEDANCE vs. FREQUENCY
MAX4385E/86E toc04
VOUT = 2VP-P
0.2
-80
2ND HARMONIC
-90
-0.5
0.01
10M
100M
-100
100k
1G
1M
MAX4385E/86E toc07
-30
-40
-50
0
-10
3RD HARMONIC
-60
VOUT = 2VP-P
AVCL = 5V/V
-20
DISTORTION (dBc)
-20
3RD HARMONIC
-60
-80
-80
10M
FREQUENCY (Hz)
100M
-20
-30
-40
-50
2ND HARMONIC
-60
-90
-90
1M
fO = 5MHz
VOUT = 2VP-P
AVCL = 1V/V
-10
-80
2ND HARMONIC
-90
0
-70
2ND HARMONIC
-70
100M
DISTORTION vs. RESISTIVE LOAD
-40
-50
10M
FREQUENCY (Hz)
-30
-70
100k
1M
100k
1G
DISTORTION vs. FREQUENCY
DISTORTION vs. FREQUENCY
VOUT = 2VP-P
AVCL = 2V/V
100M
FREQUENCY (Hz)
FREQUENCY (Hz)
0
10M
MAX4385E/86E toc08
1M
DISTORTION (dBc)
100k
MAX4385E/86E toc09
-0.6
-10
1M
FREQUENCY (Hz)
1000
OUTPUT IMPEDANCE (Ω)
0.4
0.3
10M
FREQUENCY (Hz)
FREQUENCY (Hz)
4
0
-0.1
-2
100k
VOUT = 100mVP-P
0.3
-2
-6
GAIN (dB)
0.4
MAX4385E/86E toc03
2
1
-1
VOUT = 2VP-P
MAX4385E/86E toc06
2
GAIN (dB)
4
3
MAX4385E/86E toc02
VOUT = 100mVP-P
GAIN (dB)
3
MAX4385E/86E toc01
4
SMALL-SIGNAL GAIN FLATNESS
vs. FREQUENCY
LARGE-SIGNAL GAIN
vs. FREQUENCY
SMALL-SIGNAL GAIN vs. FREQUENCY
DISTORTION (dBc)
MAX4385E/MAX4386E
Low-Cost, 230MHz, Single/Quad Op Amps with
Rail-to-Rail Outputs and ±15kV ESD Protection
3RD HARMONIC
-100
100k
1M
10M
FREQUENCY (Hz)
100M
0
200
400
600
RLOAD (Ω)
_______________________________________________________________________________________
800
1000
1200
Low-Cost, 230MHz, Single/Quad Op Amps with
Rail-to-Rail Outputs and ±15kV ESD Protection
DISTORTION vs. VOLTAGE SWING
0
DIFF PHASE (DEGREES)
-50
3RD HARMONIC
-60
-70
2ND HARMONIC
-80
-90
0.5
1.5
1.0
10 20 30 40
0.030
0.025
0.020
0.015
0.010
0.005
0
-0.005
-0.010
2.0
-60
-90
10 20 30 40
100k
50 60 70 80 90 100
IRE
-50
-60
10M
100M
1G
SMALL-SIGNAL PULSE RESPONSE
0.8
MAX4385E/86E toc14
MAX4385E/86E toc13
-40
1M
FREQUENCY (Hz)
OUTPUT VOLTAGE SWING
vs. RESISTIVE LOAD
-30
MAX4385E/86E toc12
-50
-100
0
0.7
OUTPUT VOLTAGE SWING (V)
0.6
AVCL = 1V/V
INPUT
50mV/div
0.5
0.4
VCC - VOH
0.3
0.2
OUTPUT
50mV/div
VOL - VEE
0.1
-70
1M
10M
100M
1G
0
0
100
200
300
400
FREQUENCY (Hz)
RLOAD (Ω)
SMALL-SIGNAL PULSE RESPONSE
SMALL-SIGNAL PULSE RESPONSE
AVCL = 2V/V
RF = 200Ω
INPUT
25mV/div
MAX4385E/86E toc16
100k
AVCL = 5V/V
RF = 250Ω
INPUT
10mV/div
OUTPUT
50mV/div
OUTPUT
50mV/div
20ns/div
20ns/div
500
LARGE-SIGNAL PULSE RESPONSE
AVCL = 1V/V
INPUT
1V/div
MAX4385E/86E toc18
PSR (dB)
-20
-40
-80
POWER-SUPPLY REJECTION
vs. FREQUENCY
-10
-30
-70
VOLTAGE SWING (VP-P)
0
50 60 70 80 90 100
IRE
-20
MAX4385E/86E toc15
-40
0
-10
CMR (dB)
-30
MAX4385E/86E toc17
DISTORTION (dBc)
-20
0.030
0.025
0.020
0.015
0.010
0.005
0
-0.005
-0.010
MAX4385E/86E toc11
fO = 5MHz
AVCL = 1V/V
DIFF GAIN (PERCENT)
MAX4385E/86E toc10
0
-10
COMMON-MODE REJECTION
vs. FREQUENCY
DIFFERENTIAL GAIN AND PHASE
OUTPUT
1V/div
20ns/div
20ns/div
_______________________________________________________________________________________
5
MAX4385E/MAX4386E
Typical Operating Characteristics (continued)
(VCC = 5V, VEE = 0, VCM = 1.5V, AVCL = 1V/V, RL = 100Ω to VCC/2, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(VCC = 5V, VEE = 0, VCM = 1.5V, AVCL = 1V/V, RL = 100Ω to VCC/2, TA = +25°C, unless otherwise noted.)
LARGE-SIGNAL PULSE RESPONSE
OUTPUT
1V/div
INPUT
200mV/div
OUTPUT
1V/div
MAX4385E/86E toc21
INPUT
500mV/div
AVCL = 5V/V
RF = 250Ω
1000
VOLTAGE NOISE (nV/√Hz)
AVCL = 2V/V
RF = 200Ω
VOLTAGE NOISE vs. FREQUENCY
MAX4385E/86E toc20
MAX4385E/86E toc19
LARGE-SIGNAL PULSE RESPONSE
RL = 100Ω
100
10
1
20ns/div
20ns/div
1
10
100
1k
10k
100k
FREQUENCY (Hz)
ISOLATION RESISTANCE
vs. CAPACITIVE LOAD
12
10
8
6
200
150
100
4
50
2
0
1
10
100
1k
10k
100k
0
0
100
FREQUENCY (Hz)
OPEN-LOOP GAIN vs. RESISTIVE LOAD
50
40
30
500
CROSSTALK vs. FREQUENCY
SHUTDOWN RESPONSE
-20
-30
DISABLE
-50
-60
1.5V
VOUT
0
-90
0
5V
0
-40
-80
10
100 200 300 400 500 600 700 800
RLOAD (Ω)
-70
20
0
CLOAD (pF)
-10
CROSSTALK (dB)
60
400
MAX4385E/86E toc26
VCC = 5V
70
300
0
MAX4385E/86E toc25
80
200
MAX4385E/86E toc27
1
-100
100
1k
RLOAD (Ω)
6
250
BANDWIDTH (MHz)
10
300
MAX4385E/86E toc23
14
RISO (Ω)
RL = 100Ω
CURRENT NOISE (pA/√Hz)
16
MAX4385E/86E toc22
100
SMALL-SIGNAL BANDWIDTH
vs. LOAD RESISTANCE
MAX4385E/86E toc24
CURRENT NOISE vs. FREQUENCY
OPEN-LOOP GAIN (dB)
MAX4385E/MAX4386E
Low-Cost, 230MHz, Single/Quad Op Amps with
Rail-to-Rail Outputs and ±15kV ESD Protection
10k
100k
1M
10M
100M
1G
200ns/div
FREQUENCY (Hz)
_______________________________________________________________________________________
Low-Cost, 230MHz, Single/Quad Op Amps with
Rail-to-Rail Outputs and ±15kV ESD Protection
3.0
2.5
2.0
1.5
1.0
VCC = 5V
0.5
-6.5
-7.0
-7.5
-8.0
-8.5
-10.0
-50
-25
0
25
50
75
6.5
6.0
5.5
VCC = 5V
4.0
-50
100
7.0
4.5
-9.5
-0.5
7.5
5.0
-9.0
0
MAX4385E/86E toc30
VCC = 5V
-6.0
8.0
SUPPLY CURRENT (mA)
3.5
-5.0
-5.5
MAX4385E/86E toc29
INPUT OFFSET VOLTAGE (mV)
4.0
INPUT BIAS CURRENT (µA)
MAX4385E/86E toc28
4.5
SUPPLY CURRENT
vs. TEMPERATURE
INPUT BIAS CURRENT
vs. TEMPERATURE
INPUT OFFSET VOLTAGE
vs. TEMPERATURE
-25
0
25
50
75
100
-50
TEMPERATURE (°C)
TEMPERATURE (°C)
-25
0
25
50
75
100
TEMPERATURE (°C)
Pin Description
PIN
MAX4385E
MAX4386E
SOT23
SO/TSSOP
NAME
FUNCTION
1
—
OUT
Amplifier Output
2
11
VEE
Negative Power Supply
3
—
IN+
Noninverting Input
4
—
IN-
Inverting Input
Positive Power Supply. Connect a 2.2µF and 0.1µF capacitor to GND.
5
4
VCC
—
1
OUTA
—
2
INA-
Amplifier A Inverting Input
—
3
INA+
Amplifier A Noninverting Input
—
5
INB+
Amplifier B Noninverting Input
—
6
INB-
Amplifier B Inverting Input
—
7
OUTB
Amplifier B Output
—
8
OUTC
Amplifier C Output
—
9
INC-
Amplifier C Inverting Input
—
10
INC+
Amplifier C Noninverting Input
—
12
IND+
Amplifier D Noninverting Input
—
13
IND-
Amplifier D Inverting Input
—
14
OUTD
Amplifier A Output
Amplifier D Output
_______________________________________________________________________________________
7
MAX4385E/MAX4386E
Typical Operating Characteristics (continued)
(VCC = 5V, VEE = 0, VCM = 1.5V, AVCL = 1V/V, RL = 100Ω to VCC/2, TA = +25°C, unless otherwise noted.)
MAX4385E/MAX4386E
Low-Cost, 230MHz, Single/Quad Op Amps with
Rail-to-Rail Outputs and ±15kV ESD Protection
Detailed Description
The MAX4385E/MAX4386E are single/quad, 5V, rail-torail, voltage-feedback amplifiers that employ currentfeedback techniques to achieve 450V/µs slew rates
and 230MHz bandwidths. High ±15kV ESD protection
guards against unexpected discharge. Excellent harmonic distortion and differential gain/phase performance make these amplifiers an ideal choice for a wide
variety of video and RF signal-processing applications.
RF
RG
VOUT
MAX438_E
IN
VOUT = [1+ (RF / RG)] VIN
Applications Information
The output voltage swings to within 50mV of each supply rail. Local feedback around the output stage
ensures low open-loop output impedance to reduce
gain sensitivity to load variations. The input stage permits common-mode voltages beyond VEE and to within
2.25V of the positive supply rail.
Figure 1a. Noninverting Gain Configuration
RG
RF
IN
Choosing Resistor Values
Unity-Gain Configuration
The MAX4385E/MAX4386E are internally compensated
for unity gain. When configured for unity gain, a 24Ω
resistor (RF) in series with the feedback path optimizes
AC performance. This resistor improves AC response
by reducing the Q of the parallel LC circuit formed by
the parasitic feedback capacitance and inductance.
Video Line Driver
The MAX4385E/MAX4386E are low-power, voltagefeedback amplifiers featuring bandwidths up to
230MHz, 0.1dB gain flatness to 30MHz. They are
designed to minimize differential-gain error and differential-phase error to 0.02% and 0.01°, respectively.
They have a 14ns settling time to 0.1%, 450V/µs slew
rates, and output-current-drive capability of up to
50mA, making them ideal for driving video loads.
Inverting and Noninverting Configurations
Select the gain-setting feedback (RF) and input (RG)
resistor values to fit your application. Large resistor values increase voltage noise and interact with the amplifier’s input and PC board capacitance. This can
generate undesirable poles and zeros and decrease
bandwidth or cause oscillations. For example, a noninverting gain-of-two configuration (RF = RG) using 1kΩ
resistors, combined with 8pF of amplifier input capacitance and 1pF of PC board capacitance, causes a pole
at 35.4MHz. Since this pole is within the amplifier bandwidth, it jeopardizes stability. Reducing the 1kΩ resistors to 100Ω extends the pole frequency to 353.8MHz,
but could limit output swing by adding 200Ω in parallel
with the amplifier’s load resistor (Figures 1a
and 1b).
8
VOUT
MAX438_E
VOUT = -(RF / RG) VIN
Figure 1b. Inverting Gain Configuration
Layout and Power-Supply Bypassing
These amplifiers operate from a single 5V power supply.
Bypass VCC to ground with 0.1µF and 2.2µF capacitors as
close to the pin as possible.
Maxim recommends using microstrip and stripline techniques to obtain full bandwidth. To ensure that the PC
board does not degrade the amplifier’s performance,
design it for a frequency greater than 1GHz. Pay careful attention to inputs and outputs to avoid large parasitic capacitance. Regardless of whether you use a
constant-impedance board, observe the following
design guidelines:
• Do not use wire-wrap boards; they are too inductive.
• Do not use IC sockets; they increase parasitic
capacitance and inductance.
• Use surface mount instead of through-hole components for better high-frequency performance.
• Use a PC board with at least two layers; it should be
as free from voids as possible.
• Keep signal lines as short and as straight as possible. Do not make 90° turns; round all corners.
_______________________________________________________________________________________
Low-Cost, 230MHz, Single/Quad Op Amps with
Rail-to-Rail Outputs and ±15kV ESD Protection
MAX4385E/MAX4386E
ISOLATION RESISTANCE
vs. CAPACITIVE LOAD
16
RG
RF
15
MAX438_E
VIN
VOUT
RISO (Ω)
14
RISO
CL
13
12
11
10
9
0
50 100 150 200 250 300 350 400 450 500
CLOAD (pF)
Figure 2. Driving a Capacitive Load Through an Isolation Resistor
Figure 3. Isolation Resistance vs. Capacitive Load
Rail-to-Rail Outputs,
Ground-Sensing Inputs
5
CL = 15pF
4
3
GAIN (dB)
The input common-mode range extends from (VEE 200mV) to (VCC - 2.25V) with excellent common-mode
rejection. Beyond this range, the amplifier output is a
nonlinear function of the input, but does not undergo
phase reversal or latchup.
6
The output swings to within 50mV of either power-supply rail with a 2kΩ load. The input ground sensing and
the rail-to-rail output substantially increase the dynamic
range. The input can swing 2.95VP-P and the output
can swing 4.9VP-P with minimal distortion.
2
CL = 10pF
1
0
CL = 5pF
-1
-2
-3
-4
100k
1M
Output Capacitive Loading and Stability
100M
1G
Figure 4. Small-Signal Gain vs. Frequency with Load
Capacitance and No Isolation Resistor
3
2
RISO = 15Ω
CL = 47pF
1
0
GAIN (dB)
The MAX4385E/MAX4386E are optimized for AC performance and do not drive highly reactive loads, which
decreases phase margin and may produce excessive
ringing and oscillation. Figure 2 shows a circuit that
eliminates this problem. Figure 3 is a graph of the
Optimal Isolation Resistor (RS) vs. Capacitive Load.
Figure 4 shows how a capacitive load causes excessive peaking of the amplifier’s frequency response if
the capacitor is not isolated from the amplifier by a
resistor. A small isolation resistor (usually 10Ω to 15Ω)
placed before the reactive load prevents ringing and
oscillation. At higher capacitive loads, the interaction of
the load capacitance and the isolation resistor controls
the AC performance. Figure 5 shows the effect of a
15Ω isolation resistor on closed-loop response.
10M
FREQUENCY (Hz)
-1
CL = 68pF
-2
CL = 120pF
-3
-4
-5
-6
-7
100k
1M
10M
100M
1G
FREQUENCY (Hz)
Figure 5. Small-Signal Gain vs. Frequency with Load
Capacitance and 27Ω Isolation Resistor
_______________________________________________________________________________________
9
MAX4385E/MAX4386E
Low-Cost, 230MHz, Single/Quad Op Amps with
Rail-to-Rail Outputs and ±15kV ESD Protection
ESD Protection
As with all Maxim devices, ESD protection structures
are incorporated on all pins to protect against ESD
encountered during handling and assembly. Input and
output pins of the MAX4385E/MAX4386E have extra
protection against static electricity. Maxim’s engineers
have developed state-of-the-art structures enabling
these pins to withstand ESD up to ±15kV without damage when placed in the test circuit (Figure 6). The
MAX4385E/MAX4386E are characterized for protection
to the following limits:
• ±15kV using the Human Body Model
• ±8kV using the Contact Discharge method specified
in IEC 1000-4-2
5V
CBYPASS
2.2µF
TEST
POINT A
75Ω
75Ω
TEST
POINT B
MAX438_E
VEE
220Ω
220Ω
• ±15kV using the Air-Gap Discharge method specified in IEC 1000-4-2
Human Body Model
Figure 7 shows the Human Body Model, and Figure 8
shows the current waveform it generates when discharged into a low impedance. This model consists of a
150pF capacitor charged to the ESD voltage of interest,
and then discharged into the test device through a
1.5kΩ resistor.
IEC 1000-4-2
The IEC 1000-4-2 standard covers ESD testing and
performance of finished equipment; it does not specifically refer to ICs. The MAX4385E/MAX4386E enable the
design of equipment that meets the highest level (Level
4) of IEC 1000-4-2 without the need for additional ESD
protection components. The major difference between
tests done using the Human Body Model and IEC 10004-2 is higher peak current in IEC 1000-4-2. Because
series resistance is lower in the IEC 1000-4-2 model,
the ESD-withstand voltage measured to this standard is
generally lower than that measured using the Human
Body. Figure 10 shows the IEC 1000-4-2 model and
Figure 9 shows the current waveform for the ±8kV IEC
1000-4-2 Level 4 ESD Contact Discharge test. The AirGap test involves approaching the device with a
charged probe. The Contact Discharge method connects the probe to the device before the probe is energized.
Figure 6. ESD Test Circuit
RD = 1.5kΩ
RC = 1MΩ
HIGHVOLTAGE
DC
SOURCE
CHARGE CURRENT
LIMIT RESISTOR
CS = 150pF
DISCHARGE
RESISTANCE
DEVICE
UNDER
TEST
STORAGE
CAPACITOR
Figure 7. Human Body ESD Model
IP 100%
90%
Ir
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
AMPERES
36.8%
10%
0
0
tRL
TIME
tDL
CURRENT WAVEFORM
Figure 8. Human Body Current Waveform
10
______________________________________________________________________________________
Low-Cost, 230MHz, Single/Quad Op Amps with
Rail-to-Rail Outputs and ±15kV ESD Protection
HIGHVOLTAGE
DC
SOURCE
CS
150pF
100%
90%
DISCHARGE
RESISTANCE
I PEAK
CHARGE CURRENT
LIMIT RESISTOR
I
RD
330Ω
DEVICE
UNDER
TEST
STORAGE
CAPACITOR
10%
t r = 0.7ns TO 1ns
t
30ns
60ns
Figure 9. IEC 1000-4-2 ESD Test Model
Figure 10. IEC 1000-4-2 ESD Generator Current Waveform
Pin Configurations (continued)
Chip Information
MAX4385E TRANSISTOR COUNT: 124
MAX4386E TRANSISTOR COUNT: 264
TOP VIEW
OUTA 1
14 OUTD
INA-
2
13 IND-
INA+
3
12 IND+
VCC 4
MAX4386E
11 VEE
INB+ 5
10 INC+
INB- 6
9
INC-
OUTB 7
8
OUTC
TSSOP/SO
______________________________________________________________________________________
11
MAX4385E/MAX4386E
RC
50MΩ TO
100MΩ
Package Information
SOT5L.EPS
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
TSSOP,NO PADS.EPS
MAX4385E/MAX4386E
Low-Cost, 230MHz, Single/Quad Op Amps with
Rail-to-Rail Outputs and ±15kV ESD Protection
12
______________________________________________________________________________________
Low-Cost, 230MHz, Single/Quad Op Amps with
Rail-to-Rail Outputs and ±15kV ESD Protection
SOICN.EPS
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied.
Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-1737-7600____________________13
© 2002 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
MAX4385E/MAX4386E
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
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