Maxim MAX4225 1ghz, low-power, sot23, current-feedback amplifiers with shutdown Datasheet

19-1230; Rev 2a; 6/97
KIT
ATION
EVALU
E
L
B
AVAILA
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
The MAX4223–MAX4228 are ideal for professional video
applications, with differential gain and phase errors of
0.01% and 0.02°, 0.1dB gain flatness of 300MHz, and a
1100V/µs slew rate. Total harmonic distortion (THD) of
-60dBc (10MHz) and an 8ns settling time to 0.1% suit
these devices for driving high-speed analog-to-digital
inputs or for data-communications applications. The lowpower shutdown mode on the MAX4223/MAX4224/
MAX4226/MAX4228 makes them suitable for portable
and battery-powered applications. Their high output
impedance in shutdown mode is excellent for multiplexing applications.
The single MAX4223/MAX4224 are available in spacesaving 6-pin SOT23 packages. All devices are available
in the extended -40°C to +85°C temperature range.
________________________Applications
ADC Input Buffers
Video Cameras
Data Communications
Video Line Drivers
Video Switches
Video Editors
Video Multiplexing
XDSL Drivers
RF Receivers
Differential Line Drivers
_________________Pin Configurations
____________________________Features
♦ Ultra-High Speed and Fast Settling Time:
1GHz -3dB Bandwidth (MAX4223, Gain = +1)
600MHz -3dB Bandwidth (MAX4224, Gain = +2)
1700V/µs Slew Rate (MAX4224)
5ns Settling Time to 0.1% (MAX4224)
♦ Excellent Video Specifications (MAX4223):
Gain Flatness of 0.1dB to 300MHz
0.01%/0.02° DG/DP Errors
♦ Low Distortion:
-60dBc THD (fc = 10MHz)
42dBm Third-Order Intercept (f = 30MHz)
♦ 6.0mA Quiescent Supply Current (per amplifier)
♦ Shutdown Mode:
350µA Supply Current (per amplifier)
100kΩ Output Impedance
♦ High Output Drive Capability:
80mA Output Current
Drives up to 4 Back-Terminated 75Ω Loads to
±2.5V while Maintaining Excellent Differential
Gain/Phase Characteristics
♦ Available in Tiny 6-Pin SOT23 and 10-Pin µMAX
Packages
______________Ordering Information
PART
TEMP. RANGE
MAX4223EUT-T -40°C to +85°C
6 SOT23
MAX4223ESA
8 SO
-40°C to +85°C
6
5
VEE 2
IN+ 3
Pin Configurations
continued at end
of data sheet.
4
SOT23-6
VCC
SHDN
IN-
MAX4223
MAX4224
SOT
TOP MARK
AAAD
—
Ordering Information continued at end of data sheet.
_____________________Selector Guide
PART
MIN.
GAIN
AMPS
PER
PKG.
SHUTDOWN
MODE
PINPACKAGE
MAX4223
1
1
Yes
6 SOT23, 8 SO
MAX4224
2
1
Yes
6 SOT23, 8 SO
MAX4225
1
2
No
8 SO
10 µMAX,
14 SO
TOP VIEW
OUT 1
PINPACKAGE
MAX4226
1
2
Yes
MAX4227
2
2
No
8 SO
Yes
10 µMAX,
14 SO
MAX4228
2
2
________________________________________________________________ Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800
For small orders, phone 408-737-7600 ext. 3468.
MAX4223–MAX4228
_______________General Description
The MAX4223–MAX4228 current-feedback amplifiers
combine ultra-high-speed performance, low distortion,
and excellent video specifications with low-power operation. The MAX4223/MAX4224/MAX4226/MAX4228
have a shutdown feature that reduces power-supply
current to 350µA and places the outputs into a highimpedance state. These devices operate with dual supplies ranging from ±2.85V to ±5.5V and provide a
typical output drive current of 80mA. The MAX4223/
MAX4225/MAX4226 are optimized for a closed-loop
gain of +1 (0dB) or more and have a -3dB bandwidth of
1GHz, while the MAX4224/MAX4227/MAX4228 are
compensated for a closed-loop gain of +2 (6dB) or
more, and have a -3dB bandwidth of 600MHz (1.2GHz
gain-bandwidth product).
MAX4223–MAX4228
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (VCC to VEE) ..................................................12V
Analog Input Voltage .......................(VEE - 0.3V) to (VCC + 0.3V)
Analog Input Current ........................................................±25mA
SHDN Input Voltage.........................(VEE - 0.3V) to (VCC + 0.3V)
Short-Circuit Duration
OUT to GND ...........................................................Continuous
OUT to VCC or VEE............................................................5sec
Continuous Power Dissipation (TA = +70°C)
6-Pin SOT23 (derate 7.1mW/°C above +70°C).............571mW
8-Pin SO (derate 5.9mW/°C above +70°C)...................471mW
10-Pin µMAX (derate 5.6mW/°C above +70°C) ............444mW
14-Pin SO (derate 8.3mW/°C above +70°C).................667mW
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10sec) .............................+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 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 = -5V, SHDN = 5V, VCM = 0V, RL = ∞, TA = TMIN to TMAX, unless otherwise noted. Typical values are at
TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
TA = +25°C
Input Offset Voltage
VOS
TA = TMIN to TMAX
Input Offset Voltage Drift
Input Bias Current
(Positive Input)
Input Bias Current
(Negative Input)
TYP
MAX
MAX4223/MAX4224
±0.5
±4
MAX4225–MAX4228
±0.5
±5
CONDITIONS
MIN
MAX4223/MAX4224
±6
MAX4225–MAX4228
±2
TA = +25°C
±2
TA = TMIN to TMAX
TA = +25°C
IBTA = TMIN to TMAX
mV
±7
TCVOS
IB+
UNITS
µV/°C
±10
±15
MAX4223/MAX4224
±4
MAX4225–MAX4228
±4
MAX4223/MAX4224
±20
±25
±30
MAX4225–MAX4228
µA
µA
±35
Input Resistance (Positive Input)
RIN+
700
kΩ
Input Resistance (Negative Input)
RIN-
45
Ω
Input Common-Mode
Voltage Range
VCM
±2.5
±3.2
V
TA = +25°C
55
61
TA = TMIN to TMAX
50
Common-Mode Rejection Ratio
Operating Supply Voltage
Range
Power-Supply Rejection Ratio
CMRR
VCC/VEE
PSRR
Quiescent Supply Current
(per Amplifier)
ISY
Open-Loop Transresistance
TR
Inferred from CMRR test
VCM = ±2.5V
Inferred from PSRR test
VCC = 2.85V to 5.5V,
VEE = -2.85V to -5.5V
9.0
VOUT = ±2.5V
VIL
2
V
dB
0.55
RL = 50Ω
VIH
63
6.0
IOUT
SHDN Logic High
TA = TMIN to TMAX
74
0.35
VOUT
SHDN Logic Low
68
Shutdown mode (SHDN = 0V)
RL = ∞
VOUT = ±2.5V
RL = 50Ω
Output Current (Note 2)
ISC
TA = +25°C
±5.5
Normal mode (SHDN = 5V)
Output Voltage Swing
Short-Circuit Output Current
±2.85
dB
mA
0.7
1.5
0.3
0.8
±2.5
±2.8
V
60
80
mA
140
mA
RL = short to ground
MΩ
0.8
2.0
_______________________________________________________________________________________
V
V
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
(VCC = +5V, VEE = -5V, SHDN = 5V, VCM = 0V, RL = ∞, TA = TMIN to TMAX, unless otherwise noted. Typical values are at
TA = +25°C.) (Note 1)
PARAMETER
SHDN Input Current
SYMBOL
IIL/IIH
CONDITIONS
MIN
SHDN = 0V or 5V
SHDN = 0V, VOUT = -2.5V to +2.5V
(Note 3)
Shutdown Mode Output
Impedance
10
TYP
MAX
UNITS
25
70
µA
100
kΩ
AC ELECTRICAL CHARACTERISTICS
(VCC = +5V, VEE = -5V, SHDN = 5V, VCM = 0V, AV = +1V/V for MAX4223/MAX4225/MAX4226, AV = +2V/V for MAX4224/MAX4227/
MAX4228, RL = 100Ω, TA = +25°C, unless otherwise noted.) (Note 4)
PARAMETER
-3dB Small-Signal Bandwidth
(Note 5)
Bandwidth for ±0.1dB
Gain Flatness (Note 5)
SYMBOL
BW
VOUT = 20mVp-p
BW0.1dB
VOUT = 20mVp-p
Gain Peaking
Large-Signal Bandwidth
CONDITIONS
BWLS
SR
Rise and Fall Time
MAX4223/5/6
750
1000
MAX4224/7/8
325
600
MAX4223/5/6
100
300
MAX4224/7/8
60
200
1.5
MAX4224/7/8
0.1
VOUT = 2Vp-p
VOUT = 4V step
Falling edge
Settling Time to 0.1%
TYP
MAX4223/5/6
Rising edge
Slew Rate (Note 5)
MIN
tS
VOUT = 2V step
tr, tf
VOUT = 2V step
MAX4223/5/6
250
MAX4224/7/8
330
MAX4223/5/6
850
1100
MAX4224/7/8
1400
1700
MAX4223/5/6
625
800
MAX4224/7/8
1100
1400
MAX4223/5/6
8
MAX4224/7/8
5
MAX4223/5/6
1.5
MAX4224/7/8
1.0
SHDN = 0V, f = 10MHz, MAX4223/4/6/8
Off Isolation
Crosstalk
XTALK
f = 30MHz,
RS = 50Ω
65
MAX4225/6
-68
MAX4227/8
-72
MAX
UNITS
MHz
MHz
dB
MHz
V/µs
ns
ns
dB
dB
Turn-On Time from Shutdown
tON
MAX4223/4/6/8
2
µs
Turn-Off Time to Shutdown
tOFF
MAX4223/4/6/8
300
ns
Power-Up Time
tUP
VCC, VEE = 0V to ±5V step
100
ns
Differential Gain Error
DG
RL = 150Ω (Note 6)
Differential Phase Error
DP
RL = 150Ω (Note 6)
Total Harmonic Distortion
THD
VOUT = 2Vp-p,
fC = 10MHz
RL = 100Ω
RL = 1kΩ
MAX4223/5/6
0.01
MAX4224/7/8
0.02
MAX4223/5/6
0.02
MAX4224/7/8
0.01
MAX4223/5/6
-60
MAX4224/7/8
-61
MAX4223/5/6
-65
MAX4224/7/8
-78
%
degrees
dBc
_______________________________________________________________________________________
3
MAX4223–MAX4228
DC ELECTRICAL CHARACTERISTICS (continued)
AC ELECTRICAL CHARACTERISTICS (continued)
(VCC = +5V, VEE = -5V, SHDN = 5V, VCM = 0V, AV = +1V/V for MAX4223/MAX4225/MAX4226, AV = +2V/V for MAX4224/MAX4227/
MAX4228, RL = 100Ω, TA = +25°C, unless otherwise noted.) (Note 4)
PARAMETER
SYMBOL
Output Impedance
ZOUT
Third-Order Intercept
CONDITIONS
MIN
TYP
f = 10kHz
SFDR
f = 10kHz
1dB Gain Compression
MAX
MAX4223/5/6
42
MAX4224/7/8
36
MAX4223/5/6
-61
MAX4224/7/8
-62
UNITS
Ω
2
f = 30kHz
fz = 30.1MHz
IP3
Spurious-Free Dynamic Range
dBm
dB
f = 10kHz
20
dBm
Input Noise Voltage Density
en
f = 10kHz
2
nV/√Hz
Input Noise Current Density
in+, in-
f = 10kHz
Input Capacitance (Note 7)
CIN
IN+
3
IN-
20
SO-8, SO-14
packages
Pin to pin
0.3
Pin to GND
1.0
SOT23-6, 10-pin µMAX
packages
Pin to pin
0.3
Pin to GND
0.8
pA/√Hz
pF
The MAX422_EUT is 100% production tested at TA = +25°C. Specifications over temperature limits are guaranteed by design.
Absolute Maximum Power Dissipation must be observed.
Does not include impedance of external feedback resistor network.
AC specifications shown are with optimal values of RF and RG. These values vary for product and package type, and are
tabulated in the Applications Information section of this data sheet.
Note 5: The AC specifications shown are not measured in a production test environment. The minimum AC specifications given are
based on the combination of worst-case design simulations along with a sample characterization of units. These minimum
specifications are for design guidance only and are not intended to guarantee AC performance (see AC Testing/
Performance). For 100% testing of these parameters, contact the factory.
Note 6: Input Test Signal: 3.58MHz sine wave of amplitude 40IRE superimposed on a linear ramp (0IRE to 100IRE). IRE is a unit of
video signal amplitude developed by the International Radio Engineers. 140IRE = 1V.
Note 7: Assumes printed circuit board layout similar to that of Maxim’s evaluation kit.
Note 1:
Note 2:
Note 3:
Note 4:
__________________________________________Typical Operating Characteristics
(VCC = +5V, VEE = -5V, RL = 100Ω, TA = +25°C, unless otherwise noted.)
MAX4223
SMALL-SIGNAL GAIN vs. FREQUENCY
(AVCL = +2/+5)
NORMALIZED GAIN (dB)
2
2
1
0
-1
SOT23-6
RF = 470Ω
-2
-3
0
-1
-2
AV = +5V/V
RF = 100Ω
RG = 25Ω
-3
1
0
-1
-2
-3
-4
-4
-4
-5
-5
-5
-6
-6
1
10
100
FREQUENCY (MHz)
4
2
AV = +2V/V
RF = RG = 200Ω
1
1000
AV = +1V/V
RF = 560Ω
VOUT = 2Vp-p
3
GAIN (dB)
SO-8 PACKAGE
RF = 560Ω
VIN = 20mVp-p
3
4
MAX4223-02
VIN = 20mVp-p
3
4
MAX4223-01
4
MAX4223/MAX4225/MAX4226
LARGE-SIGNAL GAIN vs. FREQUENCY
(AVCL = +1)
MAX4223-03
MAX4223
SMALL-SIGNAL GAIN vs. FREQUENCY
(AVCL = +1)
GAIN (dB)
MAX4223–MAX4228
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
-6
1
10
100
FREQUENCY (MHz)
1000
1
10
100
FREQUENCY (MHz)
_______________________________________________________________________________________
1000
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
MAX4224
SMALL-SIGNAL GAIN vs. FREQUENCY
(AVCL = +5/+10)
VIN = 20mVp-p
3
AVCL = +5V/V
RF = 240Ω
RG = 62Ω
0
-1
-2
SO-8 PACKAGE
RF = RG = 470Ω
SOT23-6 PACKAGE
RF = RG = 470Ω
-5
10
100
AVCL = +10V/V
RF = 130Ω
RG = 15Ω
-2
-3
-4
-6
1
1000
10
1000
1
0.4
MAX4223-07
VIN = 20mVp-p
AVCL = +1V/V
RF = 560Ω
VIN = 2OmVp-p
AVCL = +1V/V
RF = 560Ω
0.3
0.2
GAIN (dB)
0
-1
-2
-3
AMPLIFIER A
0
AMPLIFIER B
-0.3
0
-1
-2
-3
-4
-0.4
-4
-0.5
-5
10
100
10
1
100
100
1000
FREQUENCY (MHz)
MAX4227/MAX4228
GAIN MATCHING vs. FREQUENCY
(AVCL = +2)
MAX4225/MAX4226
CROSSTALK vs. FREQUENCY
MAX4227/MAX4228
CROSSTALK vs. FREQUENCY
-0.2
-20
-20
-30
-30
-40
-50
-60
-60
-0.4
-80
-80
-0.5
-90
-90
-100
-100
-0.6
1
10
FREQUENCY (MHz)
100
MAX4223-12
-40
-50
-70
-70
-0.3
RS = 50Ω
VOUT = 2Vp-p
-10
CROSSTALK (dB)
CROSSTALK (dB)
0
-0.1
RS = 50Ω
VOUT = 2Vp-p
-10
0
MAX4223-11
0
MAX4223-10
0.1
0.1
10
FREQUENCY (MHz)
VIN = 20mVp-p
AVCL = +2V/V
RF = RG = 470Ω
0.2
1
FREQUENCY (MHz)
0.4
0.3
-6
-0.6
1000
VIN = 20mVp-p
AVCL = +2V/V
RF = RG = 470Ω
1
-5
-6
1000
4
3
2
-0.1
-0.2
100
MAX4227/MAX4228
SMALL-SIGNAL GAIN vs. FREQUENCY
(AVCL = +2)
0.1
1
10
FREQUENCY (MHz)
MAX4225/MAX4226
GAIN MATCHING vs. FREQUENCY
(AVCL = +1)
1
GAIN (dB)
100
FREQUENCY (MHz)
4
NORMALIZED GAIN (dB)
-2
-3
-5
MAX4225/MAX4226
SMALL-SIGNAL GAIN vs. FREQUENCY
(AVCL = +1)
2
0
-1
-5
FREQUENCY (MHz)
3
1
-4
-6
-6
1
-1
NORMALIZED GAIN (dB)
-4
0
MAX4223-08
-3
2
MAX4223-09
NORMALIZED GAIN (dB)
1
AVCL = +2V/V
RF = RG = 470Ω
VOUT = 2Vp-p
3
NORMALIZED GAIN (dB)
2
1
4
MAX4223-05
VIN = 20mVp-p
2
NORMALIZED GAIN (dB)
4
MAX4223-04
4
3
MAX4224/MAX4227/MAX4228
LARGE-SIGNAL GAIN vs. FREQUENCY
(AVCL = +2)
MAX4223-06
MAX4224
SMALL-SIGNAL GAIN vs. FREQUENCY
(AVCL = +2)
1
10
100
FREQUENCY (MHz)
1000
1
10
100
1000
FREQUENCY (MHz)
_______________________________________________________________________________________
5
MAX4223–MAX4228
____________________________Typical Operating Characteristics (continued)
(VCC = +5V, VEE = -5V, RL = 100Ω, TA = +25°C, unless otherwise noted.)
____________________________Typical Operating Characteristics (continued)
(VCC = +5V, VEE = -5V, RL = 100Ω, TA = +25°C, unless otherwise noted.)
MAX4224/MAX4227/MAX4228
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY (AVCL = +2)
-10
-20
-20
-30
VCC
-50
-60
VCC
-40
-50
-60
VEE
-70
VEE
-70
-80
10
MAX4223/5/6
AVCL = +1V/V
RF = 560Ω
1
MAX4224/7/8
AVCL = +2V/V
RF = RG = 470Ω
0.1
-80
-90
-90
0.01
0.1
1
10
100
0.01
0.01
0.1
1
10
100
0.01
0.1
1
10
100
FREQUENCY (MHz)
FREQUENCY (MHz)
FREQUENCY (MHz)
SHUTDOWN MODE OUTPUT ISOLATION
vs. FREQUENCY
MAX4223/MAX4225/MAX4226
TOTAL HARMONIC DISTORTION
vs. FREQUENCY (RL = 150Ω)
MAX4223/MAX4225/MAX4226
TOTAL HARMONIC DISTORTION
vs. FREQUENCY (RL = 1kΩ)
-40
THD (dBc)
-80
MAX4224/7/8
AVCL = +2V/V
RF = RG = 470Ω
-120
-60
2ND HARMONIC
-80
0.1
1
10
100
-90
-100
-90
1000
0.1
10
1
0.1
100
10
1
100
FREQUENCY (MHz)
FREQUENCY (MHz)
FREQUENCY (MHz)
MAX4224/MAX4227/MAX4228
TOTAL HARMONIC DISTORTION
vs. FREQUENCY (RL = 150Ω)
MAX4224/MAX4227/MAX4228
TOTAL HARMONIC DISTORTION
vs. FREQUENCY (RL = 1kΩ)
TWO-TONE THIRD-ORDER INTERCEPT
vs. FREQUENCY
-40
-50
THD
THD (dBc)
-50
-60
-60
-70
THD
-70
2ND HARMONIC
2ND HARMONIC
-80
3RD HARMONIC
MAX4223-21
-40
55
THIRD-ORDER INTERCEPT (dBm)
-30
MAX4223-19
-30
-80
3RD HARMONIC
3RD HARMONIC
MAX4223-20
0.01
-70
-80
-160
-180
THD
-60
2ND HARMONIC
-70
-140
AVCL = +1V/V
RL = 1kΩ
RF = 560Ω
VOUT = 2Vp-p
-40
-50
THD
MAX4223-18
-40
-50
-60
-100
AVCL = +1V/V
RL = 150Ω
RF = 560Ω
VOUT = 2Vp-p
THD (dBc)
MAX4223/5/6
AVCL = +1V/V
RF = 560Ω
-30
MAX4223-17
0
-20
-30
MAX4223-16
20
SHUTDOWN MODE OUTPUT ISOLATION (dB)
-30
OUTPUT IMPEDANCE (Ω)
-10
-40
AVCL = +2V/V
RF = RG = 470Ω
0
100
MAX4223-14
AVCL = +1V/V
RF = 560Ω
PSRR (dB)
PSRR (dB)
0
OUTPUT IMPEDANCE vs. FREQUENCY
10
MAX4223-13
10
MAX4223-15
MAX4223/MAX4225/MAX4226
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY (AVCL = +1)
THD (dBc)
MAX4223–MAX4228
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
50
45
MAX4224/7/8
40
35
30
MAX4223/5/6
25
-90
3RD HARMONIC
-90
0.1
1
10
FREQUENCY (MHz)
6
20
-100
100
0.1
1
10
FREQUENCY (MHz)
100
10
20
30
40
50
60
70
FREQUENCY (MHz)
_______________________________________________________________________________________
80
90 100
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
MAX4223/MAX4225/MAX4226
SMALL-SIGNAL PULSE RESPONSE
(AVCL = +1)
MAX4224/MAX4227/MAX4228
SMALL-SIGNAL PULSE RESPONSE
(AVCL = +2)
MAX4223/MAX4225/MAX4226
SMALL-SIGNAL PULSE RESPONSE
(AVCL = +1, CL = 25pF)
MAX4223-22
MAX4223-24
MAX4223-23
+100mV
+50mV
+100mV
GND
INPUT
GND
INPUT
-100mV
+100mV
GND
OUTPUT
-100mV
GND
INPUT
-100mV
-50mV
+100mV
+100mV
OUTPUT
GND OUTPUT
-100mV
-100mV
GND
TIME (10ns/div)
TIME (10ns/div)
TIME (10ns/div)
MAX4224/MAX4227/MAX4228
SMALL-SIGNAL PULSE RESPONSE
(AVCL = +2, CL = 10pF)
MAX4223/MAX4225/MAX4226
LARGE-SIGNAL PULSE RESPONSE
(AVCL = +1)
MAX4223/MAX4225/MAX4226
LARGE-SIGNAL PULSE RESPONSE
(AVCL = +1, CL = 25pF)
MAX4223-25
MAX4223-27
MAX4223-26
+50mV
+2V
+2V
GND
INPUT
-50mV
+100mV
GND
OUTPUT
-100mV
GND
INPUT
GND
INPUT
-2V
-2V
+2V
+2V
OUTPUT
GND OUTPUT
-2V
-2V
GND
TIME (10ns/div)
TIME (10ns/div)
TIME (10ns/div)
MAX4224/MAX4227/MAX4228
LARGE-SIGNAL PULSE RESPONSE
(AVCL = +2)
MAX4224/MAX4227/MAX4228
LARGE-SIGNAL PULSE RESPONSE
(AVCL = +2,CL = 10pF)
MAX4224/MAX4227/MAX4228
LARGE-SIGNAL PULSE RESPONSE
(AVCL = +5)
MAX4223-28
MAX4223-30
MAX4223-29
+1V
+400mV
+1V
INPUT
GND
INPUT
GND
INPUT
-1V
-1V
-400mV
+2V
+2V
+2V
OUTPUT
GND OUTPUT
-2V
-2V
GND
OUTPUT
-2V
TIME (10ns/div)
TIME (10ns/div)
GND
GND
TIME (10ns/div)
_______________________________________________________________________________________
7
MAX4223–MAX4228
____________________________Typical Operating Characteristics (continued)
(VCC = +5V, VEE = -5V, RL = 100Ω, TA = +25°C, unless otherwise noted.)
____________________________Typical Operating Characteristics (continued)
(VCC = +5V, VEE = -5V, RL = 100Ω, TA = +25°C, unless otherwise noted.)
NORMAL
MODE
160
4
5
4
3
CURRENT (mA)
SINKING
CURRENT (µA)
6
3
IB2
150
140
SOURCING
IB+
2
130
1
SHUTDOWN
MODE
1
0
120
0
-50
-25
0
25
50
75
100
-25
-50
TEMPERATURE (°C)
0
25
50
75
3.0
75
RL = 50Ω
2.5
2.0
1.5
MAX4223-35
-1.0
-1.5
NEGATIVE OUTPUT SWING (V)
RL = OPEN
3.5
50
NEGATIVE OUTPUT SWING
vs. TEMPERATURE
MAX4223-34
4.0
25
TEMPERATURE (°C)
TEMPERATURE (°C)
4.5
POSITIVE OUTPUT SWING (V)
0
-25
-50
100
POSITIVE OUTPUT SWING
vs. TEMPERATURE
-2.0
-2.5
RL = 50Ω
-3.0
-3.5
RL = OPEN
-4.0
1.0
-4.5
-50
-25
0
25
50
TEMPERATURE (°C)
8
MAX4223-33
7
170
MAX4223-32
5
MAX4223-31
8
SHORT-CIRCUIT OUTPUT CURRENT
vs. TEMPERATURE
INPUT BIAS CURRENT
vs. TEMPERATURE
POWER-SUPPLY CURRENT PER AMPLIFIER
vs. TEMPERATURE
CURRENT (mA)
MAX4223–MAX4228
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
75
100
-50
-25
0
25
50
TEMPERATURE (°C)
_______________________________________________________________________________________
75
100
100
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
PIN
MAX4223/MAX4224
MAX4225
MAX4227
MAX4226/MAX4228
NAME
FUNCTION
FUNCTION
SOT23
SO
SO
µMAX
SO
—
1, 5
—
—
5, 7, 8, 10
N.C.
No Connect. Not internally
connected. Tie to GND for
optimum AC performance.
1
6
—
—
—
OUT
Amplifier Output
2
4
4
4
4
VEE
Negative Power-Supply
Voltage. Connect to -5V.
3
3
—
—
—
IN+
Amplifier Noninverting Input
4
2
—
—
—
IN-
Amplifier Inverting Input
Amplifier Shutdown. Connect
to +5V for normal operation.
Connect to GND for lowpower shutdown.
5
8
—
—
—
SHDN
6
7
8
10
14
VCC
—
—
1
1
1
OUTA
—
—
2
2
2
INA-
Amplifier A Inverting Input
—
—
3
3
3
INA+
Amplifier A Noninverting Input
—
—
5
7
11
INB+
Amplifier B Noninverting Input
—
—
6
8
12
INB-
Amplifier B Inverting Input
—
—
7
9
13
OUTB
—
—
—
5
6
—
—
—
6
9
Positive Power-Supply
Voltage. Connect to +5V.
Amplifier A Output
Amplifier B Output
SHDNA
Amplifier A Shutdown Input.
Connect to +5V for normal
operation. Connect to GND for
low-power shutdown mode.
SHDNB
Amplifier B Shutdown Input.
Connect to +5V for normal
operation. Connect to GND for
low-power shutdown mode.
_______________________________________________________________________________________
9
MAX4223–MAX4228
______________________________________________________________Pin Description
MAX4223–MAX4228
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
_______________Detailed Description
The MAX4223–MAX4228 are ultra-high-speed, lowpower, current-feedback amplifiers featuring -3dB
bandwidths up to 1GHz, 0.1dB gain flatness up to
300MHz, and very low differential gain and phase
errors of 0.01% and 0.02°, respectively. These devices
operate on dual ±5V or ±3V power supplies and
require only 6mA of supply current per amplifier. The
MAX4223/MAX4225/MAX4226 are optimized for
closed-loop gains of +1 (0dB) or more and have -3dB
bandwidths of 1GHz. The MAX4224/MAX4227/
MAX4228 are optimized for closed-loop gains of +2
(6dB) or more, and have -3dB bandwidths of 600MHz
(1.2GHz gain-bandwidth product).
The current-mode feedback topology of these amplifiers allows them to achieve slew rates of up to
1700V/µs with corresponding large signal bandwidths
up to 330MHz. Each device in this family has an output
that is capable of driving a minimum of 60mA of output
current to ±2.5V.
RG
RF
IN-
RINTZ
OUT
+1
+1
IN+
MAX4223
MAX4224
MAX4225
MAX4226
MAX4227
MAX4228
VIN
Theory of Operation
Since the MAX4223–MAX4228 are current-feedback
amplifiers, their open-loop transfer function is
expressed as a transimpedance:
∆VOUT
or TZ
∆IIN −
The frequency behavior of this open-loop transimpedance is similar to the open-loop gain of a voltage-feedback amplifier. That is, it has a large DC value and
decreases at approximately 6dB per octave.
Analyzing the current-feedback amplifier in a gain configuration (Figure 1) yields the following transfer function:
()
TZ S
VOUT
=G x
VIN
TZ S + G x RIN − + RF
R
where G = A V = 1 + F .
RG
()
At low gains, (G x RIN-) << RF . Therefore, unlike traditional voltage-feedback amplifiers, the closed-loop
bandwidth is essentially independent of the closedloop gain. Note also that at low frequencies, TZ >> [(G
x RIN-) + RF], so that:
VOUT
R
= G = 1+ F
VIN
RG
10
Figure 1. Current-Feedback Amplifier
Low-Power Shutdown Mode
The MAX4223/MAX4224/MAX4226/MAX4228 have a
shutdown mode that is activated by driving the SHDN
input low. When powered from ±5V supplies, the SHDN
input is compatible with TTL logic. Placing the amplifier
in shutdown mode reduces quiescent supply current to
350µA typical, and puts the amplifier output into a highimpedance state (100kΩ typical). This feature allows
these devices to be used as multiplexers in wideband
systems. To implement the mux function, the outputs of
multiple amplifiers can be tied together, and only the
amplifier with the selected input will be enabled. All of
the other amplifiers will be placed in the low-power
shutdown mode, with their high output impedance presenting very little load to the active amplifier output. For
gains of +2 or greater, the feedback network impedance of all the amplifiers used in a mux application
must be considered when calculating the total load on
the active amplifier output.
__________Applications Information
Layout and Power-Supply Bypassing
The MAX4223–MAX4228 have an extremely high bandwidth, and consequently require careful board layout,
including the possible use of constant-impedance
microstrip or stripline techniques.
______________________________________________________________________________________
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
1) Do not use wire-wrapped boards (they are too
inductive) or breadboards (they are too capacitive).
2) Do not use IC sockets. IC sockets increase reactance.
3) Keep signal lines as short and straight as possible.
Do not make 90° turns; round all corners.
4) Observe high-frequency bypassing techniques to
maintain the amplifier’s accuracy and stability.
5) In general, surface-mount components have shorter
bodies and lower parasitic reactance, giving better
high-frequency performance than through-hole components.
The bypass capacitors should include a 10nF ceramic,
surface-mount capacitor between each supply pin and
the ground plane, located as close to the package as
possible. Optionally, place a 10µF tantalum capacitor
at the power-supply pins’ point of entry to the PC board
to ensure the integrity of incoming supplies. The powersupply trace should lead directly from the tantalum
capacitor to the VCC and VEE pins. To minimize parasitic inductance, keep PC traces short and use surfacemount components. The N.C. pins should be
connected to a common ground plane on the PC board
to minimize parasitic coupling.
If input termination resistors and output back-termination resistors are used, they should be surface-mount
types, and should be placed as close to the IC pins as
possible. Tie all N.C. pins to the ground plane to minimize parasitic coupling.
Choosing Feedback and Gain Resistors
As with all current-feedback amplifiers, the frequency
response of these devices depends critically on the
value of the feedback resistor RF. RF combines with an
internal compensation capacitor to form the dominant
pole in the feedback loop. Reducing R F ’s value
increases the pole frequency and the -3dB bandwidth,
but also increases peaking due to interaction with other
nondominant poles. Increasing R F ’s value reduces
peaking and bandwidth.
Table 1 shows optimal values for the feedback resistor
(RF) and gain-setting resistor (RG) for the MAX4223–
MAX4228. Note that the MAX4224/MAX4227/MAX4228
offer superior AC performance for all gains except unity
gain (0dB). These values provide optimal AC response
using surface-mount resistors and good layout techniques. Maxim’s high-speed amplifier evaluation kits
provide practical examples of such layout techniques.
Stray capacitance at IN- causes feedback resistor
decoupling and produces peaking in the frequencyresponse curve. Keep the capacitance at IN- as low as
possible by using surface-mount resistors and by
avoiding the use of a ground plane beneath or beside
these resistors and the IN- pin. Some capacitance is
unavoidable; if necessary, its effects can be counteracted by adjusting RF. Use 1% resistors to maintain
consistency over a wide range of production lots.
Table 1. Optimal Feedback Resistor
Networks
GAIN
(V/V)
GAIN
(dB)
RF
(Ω)
RG
(Ω)
-3dB
BW
(MHz)
0.1dB
BW
(MHz)
MAX4223/MAX4225/MAX4226
1
0
560*
Open
1000
300
2
6
200
200
380
115
5
14
100
25
235
65
MAX4224/MAX4227/MAX4228
2
6
470
470
600
200
5
14
240
62
400
90
10
20
130
15
195
35
*For the MAX4223EUT, this optimal value is 470Ω.
______________________________________________________________________________________
11
MAX4223–MAX4228
To realize the full AC performance of these high-speed
amplifiers, pay careful attention to power-supply
bypassing and board layout. The PC board should
have at least two layers: a signal and power layer on
one side and a large, low-impedance ground plane on
the other. The ground plane should be as free of voids
as possible, with one exception: the inverting input pin
(IN-) should have as low a capacitance to ground as
possible. This means that there should be no ground
plane under IN- or under the components (RF and RG)
connected to it. With multilayer boards, locate the
ground plane on a layer that incorporates no signal or
power traces.
Whether or not a constant-impedance board is used, it
is best to observe the following guidelines when
designing the board:
MAX4223–MAX4228
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
DC and Noise Errors
The MAX4223–MAX4228 output offset voltage, V OUT
(Figure 2), can be calculated with the following equation:
(
RG
)
VOUT = VOS x 1 + RF /RG + IB + x RS
RF
IN-

RF 
x 1 +
 + IB − x RF
R

G
IB-
OUT
VOUT
where:
VOS = input offset voltage (in volts)
1 + RF / RG = amplifier closed-loop gain (dimensionless)
IB+ = input bias current (in amps)
IB- = inverting input bias current (in amps)
RG = gain-setting resistor (in Ω)
RF = feedback resistor (in Ω)
RS = source resistor (in Ω)
IB+
IN+
MAX4223
MAX4224
MAX4225
MAX4226
MAX4227
MAX4228
RS
Figure 2. Output Offset Voltage
The following equation represents output noise density:

RF 
en(OUT) = 1 +
x
RG 

(in +
x RS
)2
[
(
+ in − x RF || RG
)] +(en )2
2
where:
in = input noise current density (in pA/√Hz)
en = input noise voltage density (in nV/√Hz)
The MAX4223–MAX4228 have a very low, 2nV/√Hz
noise voltage. The current noise at the noninverting
input (in+) is 3pA/√Hz, and the current noise at the
inverting input (in-) is 20pA/√Hz.
An example of DC-error calculations, using the
MAX4224 typical data and the typical operating circuit
with RF = RG = 470Ω (RF || RG = 235Ω) and RS = 50Ω,
gives:
VOUT = [5 x 10-4 x (1 + 1)] + [2 x 10-6 x 50 x (1 + 1)] +
[4 x 10-6 x 470]
VOUT = 3.1mV
Calculating total output noise in a similar manner yields
the following:
(
)
en(OUT) = 1 + 1 x
2
2

  20
x 10 −12  x 235 +  2 x 10 −9 
 

12
Communication Systems
Nonlinearities of components used in a communication
system produce distortion of the desired output signal.
Intermodulation distortion (IMD) is the distortion that
results from the mixing of two input signals of different
frequencies in a nonlinear system. In addition to the
input signal frequencies, the resulting output signal
contains new frequency components that represent the
sum and difference products of the two input frequencies. If the two input signals are relatively close in frequency, the third-order sum and difference products
will fall close to the frequency of the desired output and
will therefore be very difficult to filter. The third-order
intercept (IP3) is defined as the power level at which
the amplitude of the largest third-order product is equal
to the power level of the desired output signal. Higher
third-order intercept points correspond to better linearity of the amplifier. The MAX4223–MAX4228 have a typical IP3 value of 42dBm, making them excellent choices
for use in communications systems.
ADC Input Buffers
 3
 2
−12 
 x 10
 x 50 +
en(OUT) = 10.2nV / Hz
With a 600MHz system bandwidth, this calculates to
250µV RMS (approximately 1.5mVp-p, using the sixsigma calculation).
Input buffer amplifiers can be a source of significant
errors in high-speed ADC applications. The input buffer
is usually required to rapidly charge and discharge the
ADC’s input, which is often capacitive (see the section
Driving Capacitive Loads). In addition, a high-speed
ADC’s input impedance often changes very rapidly
during the conversion cycle, requiring an amplifier with
______________________________________________________________________________________
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
small gain error. At higher capacitive loads, AC performance is limited by the interaction of load capacitance
with the isolation resistor.
Video Line Driver
Figures 7 and 8 show a suggested layout for Maxim’s
high-speed, single-amplifier evaluation boards. These
boards were developed using the techniques described
above. The smallest available surface-mount resistors
were used for the feedback and back-termination resistors to minimize the distance from the IC to these resistors, thus reducing the capacitance associated with
longer lead lengths.
SMA connectors were used for best high-frequency
performance. Because distances are extremely short,
performance is unaffected by the fact that inputs and
outputs do not match a 50Ω line. However, in applications that require lead lengths greater than 1/4 of the
wavelength of the highest frequency of interest, constant-impedance traces should be used.
Fully assembled evaluation boards are available for the
MAX4223 in an SO-8 package.
The MAX4223–MAX4228 are optimized to drive coaxial
transmission lines when the cable is terminated at both
ends, as shown in Figure 3. Note that cable frequency
response may cause variations in the signal’s flatness.
Driving Capacitive Loads
A correctly terminated transmission line is purely resistive and presents no capacitive load to the amplifier.
Although the MAX4223–MAX4228 are optimized for AC
performance and are not designed to drive highly
capacitive loads, they are capable of driving up to
25pF without excessive ringing. Reactive loads
decrease phase margin and may produce excessive
ringing and oscillation (see Typical Operating
Characteristics). Figure 4’s circuit reduces the effect of
large capacitive loads. The small (usually 5Ω to 20Ω)
isolation resistor RISO, placed before the reactive load,
prevents ringing and oscillation at the expense of a
RG
RF
RG
Maxim’s High-Speed
Evaluation Board Layout
RF
INOUT
75Ω CABLE
RT
75Ω
75Ω CABLE
IN-
OUT
IN+
MAX4223
MAX4224
MAX4225
MAX4226
MAX4227
MAX4228
RT
75Ω
Figure 3. Video Line Driver
RT
75Ω
RISO
CL
IN+
RL
MAX4223
MAX4224
MAX4225
MAX4226
MAX4227
MAX4228
Figure 4. Using an Isolation Resistor (RISO) for High
Capacitive Loads
______________________________________________________________________________________
13
MAX4223–MAX4228
very low output impedance at high frequencies to maintain measurement accuracy. The combination of high
speed, fast slew rate, low noise, and low distortion
makes the MAX4223–MAX4228 ideally suited for use as
buffer amplifiers in high-speed ADC applications.
-3dB BANDWIDTH (MHz)
40
RISING-EDGE SLEW RATE (V/µs)
Figure 5c. MAX4223 Rising-Edge Slew-Rate Distribution
400–420
925–950
875–900
825–850
775–800
725–750
0–500
1225–1250
1175–1200
1125–1150
1075–1100
975–1000
0
1025–1050
0
925–950
10
875–900
10
675–700
20
625–650
20
SIMULATION
LOWER LIMIT
30
575–600
SIMULATION
LOWER LIMIT
MAX4223-fig5d
100 UNITS
NUMBER OF UNITS
40
0–800
360–380
50
525–550
100 UNITS
825–850
320–340
Figure 5b. MAX4223 ±0.1dB Bandwidth Distribution
MAX4223-fig5c
50
14
280–300
±0.1dB BANDWIDTH (MHz)
Figure 5a. MAX4223 -3dB Bandwidth Distribution
30
240–260
0–60
1450–1500
1350–1400
1250–1300
1150–1200
1050–1100
950–1000
0
850–900
0
750–800
10
200–220
20
10
0–600
SIMULATION
LOWER LIMIT
30
160–180
20
MAX4223-fig5b
100 UNITS
40
NUMBER OF UNITS
SIMULATION
LOWER LIMIT
650–700
NUMBER OF UNITS
40
120–140
100 UNITS
30
50
MAX4223-fig5a
50
manufacturers guarantee AC specifications without
clearly stating how this guarantee is made. The
MAX4223–MAX4228 AC specifications are derived
from worst-case design simulations combined with a
sample characterization of 100 units. The AC performance distributions along with the worst-case simulation limits are shown in Figures 5 and 6. These
distributions are repeatable provided that proper board
layout and power-supply bypassing are used (see Layout
and Power-Supply Bypassing section).
80–100
AC Testing/Performance
AC specifications on high-speed amplifiers are usually
guaranteed without 100% production testing. Since
these high-speed devices are sensitive to external parasitics introduced when automatic handling equipment
is used, it is impractical to guarantee AC parameters
through volume production testing. These parasitics
are greatly reduced when using the recommended PC
board layout (like the Maxim evaluation kit).
Characterizing the part in this way more accurately represents the amplifier’s true AC performance. Some
NUMBER OF UNITS
MAX4223–MAX4228
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
FALLING-EDGE SLEW RATE (V/µs)
Figure 5d. MAX4223 Falling-Edge Slew-Rate Distribution
______________________________________________________________________________________
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
40
-3dB BANDWIDTH (MHz)
Figure 6c. MAX4224 Rising-Edge Slew-Rate Distribution
380–400
MAX4223-fig6d
1525–1550
1475–1500
1425–1450
1375–1400
1325–1350
1275–1300
1825–1850
1775–1800
1725–1750
1675–1700
0
1625–1650
0
1575–1600
10
1225–1250
20
10
RISING-EDGE SLEW RATE (V/µs)
SIMULATION
LOWER LIMIT
30
1175–1200
20
1525–1550
340–360
40
0–1100
SIMULATION
LOWER LIMIT
1475–1500
300–320
100 UNITS
NUMBER OF UNITS
40
0–1400
260–280
50
1125–1150
100 UNITS
1425–1450
220–240
Figure 6b. MAX4224 ±0.1dB Bandwidth Distribution
MAX4223-fig6c
50
NUMBER OF UNITS
180–200
±0.1dB BANDWIDTH (MHz)
Figure 6a. MAX4224 -3dB Bandwidth Distribution
30
140–160
0–40
1050–1100
850–900
950–1000
750–800
650–700
550–600
0
450–500
0
350–400
10
100–120
20
10
0–200
SIMULATION
LOWER LIMIT
30
60–80
20
MAX4223-fig6b
100 UNITS
NUMBER OF UNITS
SIMULATION
LOWER LIMIT
250–300
NUMBER OF UNITS
40
30
50
MAX4223-fig6a
100 UNITS
MAX4223–MAX4228
50
FALLING-EDGE SLEW RATE (V/µs)
Figure 6d. MAX4224 Falling-Edge Slew-Rate Distribution
______________________________________________________________________________________
15
MAX4223–MAX4228
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
Figure 7a. Maxim SOT23 High-Speed Evaluation Board
Component Placement Guide—Component Side
Figure 7b. Maxim SOT23 High-Speed Evaluation Board
PC Board Layout—Component Side
16
Figure 7c. Maxim SOT23 High-Speed Evaluation Board
PC Board Layout—Back Side
______________________________________________________________________________________
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
MAX4223–MAX4228
Figure 8a. Maxim SO-8 High-Speed Evaluation Board
Component Placement Guide—Component Side
Figure 8b. Maxim SO-8 High-Speed Evaluation Board
PC Board Layout—Component Side
Figure 8c. Maxim SO-8 High-Speed Evaluation Board
PC Board Layout—Back Side
______________________________________________________________________________________
17
MAX4223–MAX4228
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
_____________________________________________Pin Configurations (continued)
TOP VIEW
MAX4223
MAX4224
MAX4225
MAX4227
N.C. 1
8
SHDN
IN- 2
7
IN+ 3
VEE 4
OUTA 1
8
VCC
VCC
INA- 2
7
OUTB
6
OUT
INA+ 3
6
INB-
5
N.C.
VEE 4
5
INB+
SO
SO
MAX4226
MAX4228
MAX4226
MAX4228
10 VCC
OUTA 1
OUTA 1
14 VCC
INA-
2
9
OUTB
INA- 2
13 OUTB
INA+
3
8
INB-
INA+ 3
12 INB-
VEE
4
7
INB+
VEE 4
11 INB+
SHDNA
5
6
SHDNB
N.C. 5
10 N.C.
µMAX
SHDNA 6
9
SHDNB
N.C. 7
8
N.C.
SO
18
______________________________________________________________________________________
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
PART
TEMP. RANGE
PINPACKAGE
SOT
TOP MARK
MAX4224EUT-T -40°C to +85°C
6 SOT23
MAX4224ESA
-40°C to +85°C
8 SO
AAAE
—
MAX4225ESA
-40°C to +85°C
8 SO
—
MAX4226EUB
-40°C to +85°C
10 µMAX
—
MAX4226ESD
-40°C to +85°C
14 SO
—
MAX4227ESA
-40°C to +85°C
8 SO
—
MAX4228EUB
-40°C to +85°C
10 µMAX
—
MAX4228ESD
-40°C to +85°C
14 SO
—
___________________Chip Information
MAX4223/MAX4224 TRANSISTOR COUNT: 87
MAX4225–MAX4228 TRANSISTOR COUNT: 171
SUBSTRATE CONNECTED TO VEE
______________________________________________________________________________________
19
MAX4223–MAX4228
_Ordering Information (continued)
10LUMAXB.EPS
________________________________________________________Package Information
6LSOT.EPS
MAX4223–MAX4228
1GHz, Low-Power, SOT23,
Current-Feedback Amplifiers with Shutdown
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.
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© 1997 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.