Maxim MAX4258 350mhz/250mhz, 2-channel video multiplexer-amplifier Datasheet

19-1164; Rev 2; 3/01
UAL
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350MHz/250MHz, 2-Channel
Video Multiplexer-Amplifiers
_______________General Description
These devices are ideal for use in broadcast and graphics
video systems because of their low, 2pF input capacitance, channel-to-channel switching time of only 20ns,
and wide, 130MHz 0.1dB bandwidth. In addition, the combination of ultra-high speed and low power makes them
suitable for use in general-purpose high-speed applications, such as medical imaging, industrial instrumentation,
and communications systems.
The MAX4159/MAX4259 have address latching and highimpedance output disabling, allowing them to be incorporated into large switching arrays. They are available in
14-pin SO and 16-pin QSOP packages. The MAX4158/
MAX4258 have no address latching or output disabling,
but are available in space-saving 8-pin µMAX and SO
packages.
♦ Excellent Video Specifications:
0.1dB Gain Flatness to 130MHz
0.01%/0.01° Differential Gain/Phase Error
♦ High Speed:
350MHz -3dB Bandwidth (MAX4158/4159)
250MHz -3dB Bandwidth (MAX4258/4259)
700V/µs Slew Rate (MAX4158/4159)
1000V/µs Slew Rate (MAX4258/4259)
20ns Settling Time to 0.1%
♦ Fast Switching:
20ns Channel-Switching Time
<70mV Switching Transient
♦ Low Power: 100mW
♦ Directly Drive 75Ω or 50Ω Cables
♦ High Output Current Drive: >70mA
♦ Address Latch and High-Z Output Disable
______________Ordering Information
TEMP. RANGE
PIN-PACKAGE
MAX4158ESA
-40°C to +85°C
8 SO
MAX4158EUA
-40°C to +85°C
8 µMAX
MAX4159ESD
-40°C to +85°C
14 SO
MAX4159EEE
-40°C to +85°C
16 QSOP
MAX4258ESA
-40°C to +85°C
8 SO
Video-Signal Multiplexing
MAX4258EUA
-40°C to +85°C
8 µMAX
Video Crosspoint Switches
MAX4259ESD
-40°C to +85°C
14 SO
Pixel Switching
MAX4259EEE
-40°C to +85°C
16 QSOP
________________________Applications
Coaxial Cable Drivers
Workstations
High-Definition TV (HDTV)
PART
_________________Pin Configurations
TOP VIEW
Broadcast Video
MAX4158/MAX4258
Multimedia Products
High-Speed Signal Processing
IN0 1
8
A0
GND 2
7
OUT
A0
INPUT
IN1 3
6
V+
0
IN0
V- 4
5
FB
1
IN1
MAX4158/MAX4258
SO/µMAX
Pin Configurations continued at end of data sheet.
________________________________________________________________ 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
MAX4158/MAX4159/MAX4258/MAX4259
The MAX4158/MAX4159/MAX4258/MAX4259 are wideband, 2-channel, noninverting video amplifiers with input
multiplexing, capable of driving ±2.5V signals into 50Ω or
75Ω loads. These devices are current-mode feedback
amplifiers; gain is set by external feedback resistors. The
MAX4158/MAX4159 are optimized for unity gain (0dB)
with a -3dB bandwidth of 350MHz. The MAX4258/
MAX4259 are optimized for gains of two (6dB) or more
with a 250MHz -3dB bandwidth. These devices have low
(0.01%/0.01°) differential gain and phase errors, and operate from ±5V supplies.
____________________________Features
MAX4158/MAX4159/MAX4258/MAX4259
350MHz/250MHz, 2-Channel
Video Multiplexer-Amplifiers
ABSOLUTE MAXIMUM RATINGS
Continuous Power Dissipation (TA = +70°C)
8-Pin SO (derate 5.88mW/°C above +70°C).................471mW
8-Pin µMAX (derate 4.10mW/°C above +70°C) ............330mW
14-Pin SO (derate 8.33mW/°C above +70°C)...............667mW
16-Pin QSOP (derate 8.33mW/°C above +70°C)..........667mW
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-65°C to +160°C
Lead Temperature (soldering, 10s) .................................+300°C
Positive Supply Voltage (V+ to GND) ...................................+6V
Negative Supply Voltage (V- to GND).....................................-6V
Amplifier Input Voltage (IN0 or IN1) .....(V- - 0.3V) to (V+ + 0.3V)
FB Current ........................................................................±20mA
Digital Input Voltage (A0, EN, or LE) ............-0.3V to (V+ + 0.3V)
Output Short Circuit to GND (Note 1).........................Continuous
Output Short-Circuit Current to V+, V- (Note 1)........................5s
Note 1: Continuous power dissipation maximum rating must also be observed.
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
(V+ = +5V, V- = -5V, VIN = 0V, VOUT = 0V, RL = ∞, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
Operating Supply-Voltage Range
SYMBOL
CONDITIONS
MIN
TYP
V+, V-
Inferred from the PSRR test
±4.5
Input Voltage Range
VIN
Inferred from the CMRR test
±2.5
Input Offset Voltage (Either Channel)
VOS
±1
Input Offset Voltage Temperature
Coefficient (Either Channel)
TCVOS
2
Input Bias Current (Channel On)
IIN
FB Pin Bias Current
IFB
Input Resistance
RIN
TA = +25°C
MAX
UNITS
±5.5
V
±6
mV
±3.0
±2
TA = TMIN to TMAX
V
µV/°C
±10
±18
TA = +25°C
±2
TA = TMIN to TMAX
±12
±20
µA
µA
Channel on
100
550
kΩ
Channel off
1
20
MΩ
50
Ω
40
mΩ
1
10
MΩ
VOUT = -2.5V to 2.5V, RL = 100Ω
1.0
3.0
MΩ
CMRR
VIN = -2.5V to 2.5V
50
60
dB
DC Power-Supply Rejection Ratio
PSRR
Open loop, V+ = +4.5V to +5.5V,
V- = -4.5V to -5.5V
60
78
dB
Output Voltage Swing
VOUT
RL = open circuit
±3.0
±4.0
RL = 50Ω
±2.5
±3.5
Output Current
IOUT
70
100
FB Pin Input Resistance
Output Resistance
RIN(FB)
ROUT
Disabled Output Resistance
ROUT(d)
Open-Loop Transimpedance
ZT
DC Common-Mode Rejection Ratio
Output Short-Circuit Current
Positive Supply Current
Negative Supply Current
2
VIN = -2.5V to 2.5V
ISC
I+
I-
f = 0Hz
MAX4159/MAX4259 only, EN = 5V,
VOUT = -3.0V to 3.0V (Note 2)
VOUT = -2.5V to 2.5V
V
mA
Sinking or sourcing to ground
120
MAX4158/MAX4258
10.9
13.0
EN = GND, MAX4159/MAX4259
10.9
13.0
EN = V+, MAX4159/MAX4259
6.3
8.0
MAX4158/MAX4258
9.9
12.0
EN = GND, MAX4159/MAX4259
9.9
12.0
EN = V+, MAX4159/MAX4259
5.0
7.0
_______________________________________________________________________________________
mA
mA
mA
350MHz/250MHz, 2-Channel
Video Multiplexer-Amplifiers
(V+ = +5V, V- = -5V, VIN = 0V, VOUT = 0V, RL = ∞, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
0.8
V
-2
-20
µA
130
300
µA
TYP
MAX
UNITS
LOGIC CHARACTERISTICS (Note 3)
Logic-Low Threshold
VIL
Logic-High Threshold
VIH
Logic-Low Input Current
IIL
VIL = 0
Logic-High Input Current
IIH
VIH = 5.5V, V+ = +5.5V
2.0
V
AC ELECTRICAL CHARACTERISTICS—MAX4158/MAX4159
(V+ = +5V, V- = -5V, VIN = 0V, VOUT = 0V, RL = 100Ω, TA = +25°C, unless otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
MIN
AMPLIFIER CHARACTERISTICS
-3dB Bandwidth
BW
AV = 0dB, VIN = 20mVp-p (Note 4)
350
MHz
BW(0.1)
AV = 0dB, VIN = 20mVp-p (Note 4)
100
MHz
FPBW
AV = 0dB, VOUT = 2Vp-p (Note 4)
155
MHz
SR
AV = 0dB, VOUT = 2Vp-p (Note 4)
700
V/µs
Settling Time to 0.1%
tS
VOUT = 2V step, AV = 0dB (Note 4)
10
ns
Differential Gain Error
DG
AV = 0dB (Notes 4, 5)
0.01
%
Differential Phase Error
DP
AV = 0dB (Notes 4, 5)
0.01
degrees
Bandwidth for ±0.1dB Gain Flatness
Full-Power Bandwidth
Slew Rate
Channel-to-Channel Crosstalk
Xtalk
f = 30MHz, RS = 50Ω, AV = 0dB,
VIN = ±2Vp-p (Note 4)
70
dB
Output Impedance
ZOUT
f = 30MHz, AV = 0dB (Note 4)
9
Ω
Total Harmonic Distortion
THD
f = 30MHz, VOUT = 2Vp-p,
AV = 0dB (Note 4)
50
dBc
Off-Isolation (MAX4159 only)
AISO
f = 30MHz, AV = 0dB, EN = 5V,
VIN = ±2Vp-p (Note 4)
105
dB
Output Capacitance
COUT
3
pF
Input Capacitance
CIN
Channel on or off
2
pF
Input Voltage-Noise Density
en
f = 100kHz
2
nV/√Hz
Input Current-Noise Density
FB Current-Noise Density
SWITCHING CHARACTERISTICS
Channel Switching Time
in
f = 100kHz
2
pA/√Hz
in(FB)
f = 100kHz
22
pA/√Hz
tSW
(Notes 6, 7)
20
ns
Address Setup Time
tS
TA = TMIN to TMAX (Notes 6, 8)
10
Address Hold Time
tTH
TA = TMIN to TMAX (Notes 6, 8)
10
Latch Propagation Delay
tLPD
(Note 6)
Latch Pulse Width
tLPW
TA = TMIN to TMAX (Notes 6, 8)
Enable Delay Time
tPDE
(Notes 6, 9)
20
ns
Disable Delay Time
tPDD
(Notes 6, 9)
20
ns
Switching Transient
VTRAN
±70
mV
AV = 0dB (Notes 4, 10)
ns
ns
20
10
ns
ns
_______________________________________________________________________________________
3
MAX4158/MAX4159/MAX4258/MAX4259
DC ELECTRICAL CHARACTERISTICS (continued)
MAX4158/MAX4159/MAX4258/MAX4259
350MHz/250MHz, 2-Channel
Video Multiplexer-Amplifiers
AC ELECTRICAL CHARACTERISTICS—MAX4258/MAX4259
(V+ = +5V, V- = -5V, VIN = 0V, VOUT = 0V, RL = 100Ω, TA = +25°C, unless otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
AMPLIFIER CHARACTERISTICS
-3dB Bandwidth
BW
AV = 6dB, VIN = 20mVp-p (Note 4)
250
MHz
BW(0.1)
AV = 6dB, VIN = 20mVp-p (Note 4)
130
MHz
FPBW
AV = 6dB, VOUT = 2Vp-p (Note 4)
200
MHz
Slew Rate
SR
AV = 6dB, VOUT = 2Vp-p (Note 4)
1000
V/µs
Settling Time to 0.1%
tS
VOUT = 2V step, AV = 6dB (Note 4)
10
ns
Differential Gain Error
DG
AV = 6dB (Notes 4, 5)
0.01
%
Differential Phase Error
DP
AV = 6dB (Notes 4, 5)
Bandwidth for ±0.1dB Gain Flatness
Full-Power Bandwidth
0.02
degrees
70
dB
Channel-to-Channel Crosstalk
Xtalk
f = 30MHz, RS = 50Ω, AV = 6dB,
VIN = ±1Vp-p (Note 4)
Output Impedance
ZOUT
f = 30MHz, AV = 6dB (Note 4)
9
Ω
Total Harmonic Distortion
THD
f = 30MHz, VOUT = 2Vp-p,
AV = 6dB (Note 4)
50
dBc
Off-Isolation (MAX4259)
AISO
f = 30MHz, AV = 6dB, EN = 5V,
VIN = ±1Vp-p (Note 4)
110
dB
Output Capacitance
COUT
3
pF
Input Capacitance
CIN
Channel on or off
2
pF
Input Voltage-Noise Density
en
f = 100kHz
2
nV/√Hz
Input Current-Noise Density
in
f = 100kHz
2
pA/√Hz
in(FB)
f = 100kHz
22
pA/√Hz
tSW
(Notes 6, 7)
20
ns
FB Current-Noise Density
SWITCHING CHARACTERISTICS
Channel-Switching Time
Address-Setup Time
tS
TA = TMIN to TMAX (Notes 6, 8)
10
ns
Address-Hold Time
tTH
TA = TMIN to TMAX (Notes 6, 8)
10
ns
Latch Propagation Delay
tLPD
(Note 6)
Latch Pulse Width
tLPW
TA = TMIN to TMAX (Notes 6, 8)
Enable Delay Time
tPDE
(Notes 6, 9)
Disable Delay Time
tPDD
(Notes 6, 9)
Switching Transient
VTRAN
AV = 6dB (Notes 4, 10)
20
10
ns
ns
20
ns
20
ns
±90
mV
Note 2: Does not include external feedback network resistance.
Note 3: Applies to all digital input pins (EN, LE, and A0).
Note 4: Specified with feedback network chosen for optimal AC performance. See Tables 1 and 2 for recommended component
values.
Note 5: 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 = 1.0V.
Note 6: See timing diagram (Figure 5).
Note 7: Channel-switching time specified for switching between the two input channels; does not include signal rise/fall times for
switching between channels with different input voltages.
Note 8: Guaranteed by design; not production tested.
Note 9: Output enable/disable delay times do not include amplifier output slewing times.
Note 10: Switching transient measured while switching between two grounded channels.
4
_______________________________________________________________________________________
350MHz/250MHz, 2-Channel
Video Multiplexer-Amplifiers
VIN = 20mVp-p
AV = +1V/V
RF = 430Ω
RL = 100Ω
-6
VIN = 20mVp-p
AV = +1V/V
RF = 430Ω
RL = 100Ω
10
100
1000
-2
4Vp-p OUTPUT
-4
AV = +1V/V
RF = 430Ω
RL = 100Ω
-6
-8
-0.8
1
1
10
100
1
1000
10
100
1000
FREQUENCY (MHz)
FREQUENCY (MHz)
FREQUENCY (MHz)
MAX4258/MAX4259
SMALL-SIGNAL FREQUENCY RESPONSE
MAX4258/MAX4259
GAIN FLATNESS vs. FREQUENCY
MAX4258/MAX4259
LARGE-SIGNAL FREQUENCY RESPONSE
6.0
2
VIN = 20mVp-p
AV = +2V/V
RF = RG = 510Ω
RL = 100Ω
5.8
5.6
VIN = 20mVp-p
AV = +2V/V
RF = RG = 510Ω
RL = 100Ω
5.4
1
10
100
10
100
1000
10
100
1000
FREQUENCY (MHz)
MAX4159
OFF ISOLATION vs. FREQUENCY
MAX4259
OFF ISOLATION vs. FREQUENCY
MAX4158/MAX4159
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
-20
-40
-60
-80
-100
-120
-60
-80
-100
-160
100
FREQUENCY (MHz)
1000
-30
-40
-50
-70
AV = +2V/V
RL = 100Ω
RF = RG = 510Ω
-80
-180
10
PSRR(-)
-60
-140
-180
0
-10
-20
-120
AV = +1V/V
RL = 100Ω
RF = 430Ω
10
PSRR (dB)
GAIN (dB)
-40
IN0 = ±1V
IN1 = GND
A0 = GND
EN = 5V
0
MAX4158/59-07b
-20
20
MAX4158/59-07a
IN0 = ±2V
IN1 = GND
A0 = GND
EN = 5V
1
1
FREQUENCY (MHz)
0
-160
AV = +2V/V
RF = RG = 510Ω
RL = 100Ω
FREQUENCY (MHz)
20
-140
2
-2
1
1000
4Vp-p OUTPUT
0
5.2
-2
4
MAX4158/59-08
0
2Vp-p OUTPUT
6
GAIN (dB)
GAIN (dB)
6
4
8
MAX4158/59-05
6.2
MAX4158/59-04
8
GAIN (dB)
-0.4
-0.6
-8
GAIN (dB)
-0.2
MAX4158/59-06
-4
GAIN (dB)
-2
2Vp-p OUTPUT
0
0
GAIN (dB)
GAIN (dB)
0
2
MAX4158/59-02
0.2
MAX4158/59-01
2
MAX4158/MAX4159
LARGE-SIGNAL FREQUENCY RESPONSE
MAX4158/MAX4159
GAIN FLATNESS vs. FREQUENCY
MAX4158/59-03
MAX4158/MAX4159
SMALL-SIGNAL FREQUENCY RESPONSE
PSRR(+)
AV = +1V/V
RL = 100Ω
RF = 430Ω
-90
1
10
100
FREQUENCY (MHz)
1000
0.01
0.1
1
10
100
FREQUENCY (MHz)
_______________________________________________________________________________________
5
MAX4158/MAX4159/MAX4258/MAX4259
__________________________________________Typical Operating Characteristics
(V+ = +5V, V- = -5V, TA = +25°C, unless otherwise noted.)
____________________________Typical Operating Characteristics (continued)
(V+ = +5V, V- = -5V, TA = +25°C, unless otherwise noted.)
PSRR(-)
-50
PSRR(+)
AV = +2V/V
RL = 100Ω
RF = RG = 510Ω
-70
-80
-50
-60
-80
0.1
1
MAX4258/MAX4259
0.1
MAX4158/MAX4159
-100
0.01
MAX4258/MAX4259:
RF = RG = 510Ω, AV = 2
10
-90
-90
1
10
0.01
1
100
10
100
0.01
1000
1
0.1
10
FREQUENCY (MHz)
FREQUENCY (MHz)
MAX4158/MAX4159
CHANNEL-TO-CHANNEL GAIN MATCHING
vs. FREQUENCY
MAX4258/MAX4259
CHANNEL-TO-CHANNEL GAIN MATCHING
vs. FREQUENCY
MAX4158/MAX4159
TOTAL HARMONIC DISTORTION
vs. FREQUENCY
±0.002
±0.004
±0.010
±0.012
-20
AV = +2V/V
RL = 100Ω
RF = RG = 510Ω
VIN = 20mVp-p
±0.006
±0.008
±0.010
-30
±0.012
-40
±0.014
±0.016
±0.016
-70
±0.018
±0.018
-80
±0.020
±0.020
-90
1
10
100
1
10
100
THD
-50
-60
±0.014
AV = +1V/V
VOUT = 2Vp-p
RL = 100Ω
RF = 430Ω
-10
THD (dBc)
±0.008
GAIN ERROR (dB)
AV = +1V/V
RL = 100Ω
RF = 430Ω
VIN = 20mVp-p
±0.006
MAX4158/59-14a
±0.004
0
MAX4158/59-13
0.000
MAX4158/59-12
0.000
3RD
2ND
1
10
FREQUENCY (MHz)
FREQUENCY (MHz)
MAX4258/MAX4259
TOTAL HARMONIC DISTORTION
vs. FREQUENCY
MAX4158/MAX4159
LARGE-SIGNAL PULSE RESPONSE
MAX4258/MAX4259
LARGE-SIGNAL PULSE RESPONSE
MAX4158/59-16
MAX4158/59-15
AV = +2V/V
VOUT = 2Vp-p
RL = 100Ω
RF = RG = 510Ω
-20
-30
MAX4158/59-14b
-10
100
FREQUENCY (MHz)
0
THD
-40
+2V
+1V
IN
IN
0V
0V
+2V
+2V
OUT
OUT
0V
0V
-50
-60
3RD
-70
-80
2ND
-90
-100
1
10
100
10ns/div
10ns/div
FREQUENCY (MHz)
6
100
FREQUENCY (MHz)
±0.002
GAIN ERROR (dB)
-40
-70
-60
MAX4158/MAX4159:
RF = 430Ω, AV = 1
OUTPUT IMPEDANCE (Ω)
-30
GAIN (dB)
-20
-20
-40
VIN = ±2Vp-p (MAX4158/MAX4159)
VIN = ±1Vp-p (MAX4258/MAX4259)
RS = 50Ω
RL = 100Ω
-10
-10
-30
OUTPUT IMPEDANCE vs. FREQUENCY
100
MAX4158/59-10
0
PSRR (dB)
CROSSTALK vs. FREQUENCY
0
MAX4158/59-09
10
MAX4158/59-11
MAX4258/MAX4259
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
THD (dBc)
MAX4158/MAX4159/MAX4258/MAX4259
350MHz/250MHz, 2-Channel
Video Multiplexer-Amplifiers
_______________________________________________________________________________________
350MHz/250MHz, 2-Channel
Video Multiplexer-Amplifiers
MAX4158/MAX4159
SMALL-SIGNAL PULSE RESPONSE
MAX4158/MAX4159 LARGE-SIGNAL
PULSE RESPONSE (CL = 20pF)
MAX4258/MAX4259
SMALL-SIGNAL PULSE RESPONSE
MAX4158/59-17
MAX4158/59-19
MAX4158/59-18
+100mV
+50mV
+2V
0V IN
0V IN
IN
-100mV
-50mV
0V
+100mV
+100mV
+2V
0V OUT
0V OUT
OUT
-100mV
-100mV
0V
10ns/div
10ns/div
10ns/div
MAX4258/MAX4259 LARGE-SIGNAL
PULSE RESPONSE (CL = 20pF)
MAX4158/MAX4159 SMALL-SIGNAL
PULSE RESPONSE (CL = 20pF)
MAX4258/MAX4259 SMALL-SIGNAL
PULSE RESPONSE (CL = 20pF)
MAX4158/59-22
MAX4158/59-21
MAX4158/59-20
+1V
+100mV
+50mV
IN
0V IN
0V IN
0V
-100mV
-50mV
+2V
+100mV
+100mV
OUT
0V OUT
0V OUT
0V
-100mV
-100mV
10ns/div
10ns/div
10ns/div
MAX4158/MAX4159
ADDRESS SWITCHING TRANSIENT
MAX4258/MAX4259
ADDRESS SWITCHING TRANSIENT
MAX4159/MAX4259
EN SWITCHING DELAY
MAX4158/59-24
MAX4158/59-23
MAX4158/59-25
+6V
+6V
+4V
+4V
EN
+2V
+2V
+2V
0V
0V
0V
+100mV
+100mV
+2V
0V OUT
0V OUT
+1V OUT
-100mV
0V
-100mV
20ns/div
+4V
A0
A0
IN0 = IN1 = 0V
+6V
IN0 = IN1 = 0V
20ns/div
20ns/div
_______________________________________________________________________________________
7
MAX4158/MAX4159/MAX4258/MAX4259
____________________________Typical Operating Characteristics (continued)
(V+ = +5V, V- = -5V, TA = +25°C, unless otherwise noted.)
____________________________Typical Operating Characteristics (continued)
(V+ = +5V, V- = -5V, TA = +25°C, unless otherwise noted.)
100
DIFF PHASE (deg)
0.04
0.03
0.02
0.01
0.00
-0.01
-0.02
-0.03
-0.04
0
0
100
0.04
0.03
0.02
0.01
0.00
-0.01
-0.02
-0.03
-0.04
100
MAX4158/59-28
EN = 0V
I+
11
I-
10
9
8
0
100
-60 -40 -20
0
20
40
60
IRE
IRE
TEMPERATURE (°C)
TRANSIMPEDANCE
vs. TEMPERATURE
INPUT BIAS CURRENT
vs. TEMPERATURE
FB PIN BIAS CURRENT
vs. TEMPERATURE
3.00
2.75
2.50
0.25
0
20
40
60
80
-5
-60 -40 -20
0
20
40
60
80
-60 -40 -20
100
0
20
40
NEGATIVE OUTPUT SWING
vs. TEMPERATURE
4.5
NO LOAD
4.0
50Ω LOAD
3.0
-3.0
NEGATIVE OUTPUT SWING (V)
MAX4158/59-32
5.0
50Ω LOAD
-3.5
NO LOAD
-4.0
-4.5
-5.0
-60 -40 -20
0
20
40
60
TEMPERATURE (°C)
80
100
60
TEMPERATURE (°C)
TEMPERATURE (°C)
POSITIVE OUTPUT SWING
vs. TEMPERATURE
POSITIVE OUTPUT SWING (V)
MAX4158/59-31
-4
TEMPERATURE (°C)
3.5
100
-3
-0.25
100
80
-2
MAX4158/59-33
0
100
-1
-0.50
-60 -40 -20
80
0
BIAS CURRENT (µA)
3.25
0.50
MAX4158/59-30
MAX4158/59-29
3.50
8
12
MAX4158/59-27
0.04
0.03
0.02
0.01
0.00
-0.01
-0.02
-0.03
-0.04
SUPPLY CURRENT
vs. TEMPERATURE
SUPPLY CURRENT (mA)
0
DIFF GAIN (%)
MAX4158/59-26
0.04
0.03
0.02
0.01
0.00
-0.01
-0.02
-0.03
-0.04
MAX4258/MAX4259
DIFFERENTIAL GAIN AND PHASE
INPUT BIAS CURRENT (µA)
DIFF PHASE (deg)
DIFF GAIN (%)
MAX4158/MAX4159
DIFFERENTIAL GAIN AND PHASE
TRANSIMPEDANCE (MΩ)
MAX4158/MAX4159/MAX4258/MAX4259
350MHz/250MHz, 2-Channel
Video Multiplexer-Amplifiers
-60 -40 -20
0
20
40
60
80
TEMPERATURE (°C)
_______________________________________________________________________________________
100
350MHz/250MHz, 2-Channel
Video Multiplexer-Amplifiers
OUTPUT SHORT-CIRCUIT CURRENT
vs. TEMPERATURE
INPUT OFFSET VOLTAGE
vs. TEMPERATURE
SHORT-CIRCUIT CURRENT (mA)
OFFSET VOLTAGE (V)
1.25
1.00
0.75
MAX4158/59-35
150
MAX4158/59-34
1.50
POSITIVE OUTPUT
140
130
120
NEGATIVE OUTPUT
110
100
0.50
-60 -40 -20
0
20
40
60
80
-60 -40 -20
100
0
20
40
60
80
100
TEMPERATURE (°C)
TEMPERATURE (°C)
______________________________________________________________Pin Description
PIN
MAX4159
MAX4259
MAX4158
MAX4258
NAME
FUNCTION
SO
QSOP
—
1
1
EN
Output Enable Logic Input. Connect EN to logic low or leave open for
normal operation. Connect to logic high to disconnect amplifier output
(output is high impedance).
1
3
3
IN0
Amplifier Input, Channel 0
2
2, 4, 6,
8, 10
2, 4, 6,
9, 11
GND
3
5
5
IN1
Amplifier Input, Channel 1
—
—
7, 15
N.C.
No Connection. Not internally connected. Connect to ground plane for
best RF performance.
4
7
8
V-
Negative Power-Supply Voltage
5
9
10
FB
Amplifier Feedback Input
6
11
12
V+
Positive Power-Supply Voltage
7
12
13
OUT
8
13
14
A0
Channel-Address Logic Input (see Truth Table)
—
14
16
LE
Latch-Enable Logic Input (see Truth Table)
Power Supply, Analog and Digital Ground. Connect GND to ground plane
for best RF performance.
Amplifier Output
_______________________________________________________________________________________
9
MAX4158/MAX4159/MAX4258/MAX4259
____________________________Typical Operating Characteristics (continued)
(V+ = +5V, V- = -5V, TA = +25°C, unless otherwise noted.)
MAX4158/MAX4159/MAX4258/MAX4259
350MHz/250MHz, 2-Channel
Video Multiplexer-Amplifiers
_______________Detailed Description
The MAX4158/MAX4159 are optimized for closed-loop
gains (AVCL) of 1V/V (0dB) or greater; the MAX4258/
MAX4259 are optimized for closed-loop gains of 2V/V
(6dB) or greater. These low-power, high-speed, current-mode feedback amplifiers operate from ±5V supplies. They drive video loads (including 50Ω and 75Ω
cables) with excellent distortion characteristics.
Differential gain and phase errors are 0.01%/0.01° for
MAX4158/MAX4159 and 0.01%/0.02° for MAX4258/
MAX4259, respectively.
The input multiplexers feature very short switching
times and small switching transients. They also have
high input resistance and constant input capacitance,
so overall input impedance can be set by external input
terminating resistors. Each video input is isolated by an
AC-ground pin, which reduces channel-to-channel
capacitance and minimizes crosstalk.
The MAX4159/MAX4259 have address latching and an
output enable function that places the output in a highimpedance state. These functions allow multiple
mux/amps to be paralleled together to form larger
switching arrays.
________________________Truth Tables
Input Control Logic
LOGIC
INPUTS
AMPLIFIER
INPUT
A0
0
0
IN0
Channel 0 selected
0
1
IN1
Channel 1 selected
X
[LAST]
Theory of Operation
Since the MAX4158/MAX4159/MAX4258/MAX4259 are
current-mode feedback amplifiers, their open-loop
transfer function is expressed as a transimpedance,
∆V OUT /∆I FB , or Z T . The frequency behavior of this
open-loop transimpedance is similar to the open-loop
gain of a voltage-mode feedback amplifier. That is, it
has a large DC value and decreases at approximately
6dB per octave at high frequency.
Analyzing the current-mode feedback amplifier in a
gain configuration (Figure 1) yields the following transfer function:
VOUT / VIN = G x ZT(S) / (ZT(S) + G x RIN(FB) + RF)
where G = AVCL = 1 + RF / RG.
At low gains, G x RIN(FB) << RF. Therefore, unlike traditional voltage-mode feedback amplifiers, the closedloop bandwidth is essentially independent of
closed-loop gain. Note also that at low frequencies,
ZT >> [G x RIN(FB) + RF] so:
VOUT / VIN = G = 1 + RF / RG
Layout and Power-Supply Bypassing
The MAX4158/MAX4159/MAX4258/MAX4259 have
extremely high bandwidth, and consequently require
careful board layout, including the possible use of constant-impedance microstrip or stripline techniques.
FUNCTION
LE
1
__________Applications Information
RG
RF
Channel addresses latched;
retains last input address.
FB
X = Don’t Care
MAX4159/MAX4259
Output Control Logic
RIN(FB)
ZT
LOGIC
INPUT
( EN )
AMPLIFIER
OUTPUT
0
On
Output on
1
Off
Output off; high impedance
10
+1
FUNCTION
All logic levels (EN, LE, and A0) default low (0) if left open circuit.
Output disable is completely independent of input address and
latch.
OUT
+1
IN0
VIN
IN1
Figure 1. Current-Mode Feedback Amplifier
______________________________________________________________________________________
MAX4158
MAX4159
MAX4258
MAX4259
350MHz/250MHz, 2-Channel
Video Multiplexer-Amplifiers
1) Do not use wire-wrap boards (they are much too
inductive) or breadboards (they are much too
capacitive).
2) Do not use IC sockets. IC sockets increase reactances.
3) Keep lines as short and as 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) Bear in mind that, in general, surface-mount components have shorter bodies and lower parasitic reactance, giving much 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’ points 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 V+ and V- pins. To minimize parasitic
inductance, keep PC traces short and use surfacemount components.
Ground pins have been placed between input channels
to minimize crosstalk between the two input channels.
(The grounds extend inside the package all the way to
the silicon.) These pins should be connected to a common ground plane on the PC board.
Input termination resistors and output back-termination
resistors, if used, should be surface-mount types, and
should be placed as close to the IC pins as possible.
Choosing Feedback
_________________and Gain Resistors
As with all current-mode feedback amplifiers, the frequency response of the MAX4158/MAX4159/MAX4258/
MAX4259 is critically dependent on the value of the
feedback resistor RF. RF, in conjunction with an internal
compensation capacitor, forms the dominant pole in the
feedback loop. Reducing RF’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.
Tables 1 and 2 show optimal values for the feedback
resistor (RF) and gain-setting resistor (RG) for all parts.
Note that the MAX4258/MAX4259 offer superior AC performance for all gains except unity gain (0dB). These
values provide optimal AC response using surfacemount resistors and good layout techniques. The
MAX4159/MAX4259 evaluation kit provides a practical
example of such layout techniques.
Stray capacitance at FB causes feedback resistor
decoupling and produces peaking in the frequencyresponse curve. Keep the capacitance at FB as low as
possible by using surface-mount resistors, and avoiding the use of a ground plane beneath or beside these
resistors and the FB pin. Some capacitance is unavoidable; if necessary, its effects can be counteracted by
adjusting RF. 1% resistors are recommended to maintain consistency over a wide range of production lots.
Table 1. MAX4158/MAX4159 Bandwidth
and Gain vs. Gain-Setting Resistors
GAIN
RG
(Ω)
RF
(Ω)
-3dB BW
(MHz)
0.1dB BW
(MHz)
0
∞
430
350
100
2
6
110
110
200
110
5
14
32.5
130
80
12
10
20
14.5
130
40
6
(V/V)
(dB)
1
______________________________________________________________________________________
11
MAX4158/MAX4159/MAX4258/MAX4259
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 side. The ground plane should be as free of
voids as possible, with one exception: the feedback pin
(FB) should have as low a capacitance to ground as
possible. This means that there should be no ground
plane under FB 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.
Regardless of whether or not a constant-impedance
board is used, it is best to observe the following guidelines when designing the board:
MAX4158/MAX4159/MAX4258/MAX4259
350MHz/250MHz, 2-Channel
Video Multiplexer-Amplifiers
Table 2. MAX4258/MAX4259 Bandwidth
and Gain vs. Gain-Setting Resistors
(dB)
RG
(Ω)
RF
(Ω)
-3dB BW
(MHz)
0.1dB BW
(MHz)
2
6
510
510
250
130
5
14
45
180
195
92
10
20
20
180
90
14
DC Errors and Noise
The MAX4158/MAX4159/MAX4258/MAX4259 output
offset voltage, VOUT (Figure 2) can be calculated with
the following equation:
VOUT = VOS x [1 + RF / RG] + IB x RS x [1 + RF / RG] +
IFB x RF
where:
VOS
= input offset voltage (in volts)
1 + RF / RG = amplifier closed-loop gain (dimensionless)
IB
= input bias current (in amps)
IFB
= feedback input bias current (in amps)
RG
RF
(
) (
)
en OUT = 1 + 1 x
GAIN
(V/V)
Calculating total output noise in a similar manner yields
the following:
2
2
2





−12 
−12 
−9 
 2 x 10  x 50 +  22 x 10  x 255 +  2 x 10 




(
)
en OUT = 11.9nV/ Hz
With a 200MHz system bandwidth, this calculates to
168µVRMS (approximately 1.01mVp-p, using the sixsigma calculation).
Video Line Driver
The MAX4158/MAX4159/MAX4258/MAX4259 are optimized to drive coaxial transmission lines when the
cable is terminated at both ends (Figure 3). Cable frequency response may cause variations in the flatness
of the signal.
RG
= gain-setting resistor (in ohms)
= feedback resistor (in ohms)
RS
= source resistor (in ohms)
The following equation represents output noise density:
(
) (
[in
]
FB
)
IFB
en OUT = 1+RF /RG x
x RS
2
(
OUT
VOUT
)
+ in FB x RF || RG 
 ( )

2
[ ]
+ en
2
where:
in = input noise current density (in A/√Hz)
en = input noise voltage density (in V/√Hz)
The MAX4158/MAX4159/MAX4258/MAX4259 have a
very low, 2nV/√Hz noise voltage. The current noise at
the input (in) is 2pA/√Hz, and the current noise at the
feedback input (in(FB)) is 22pA/√Hz.
An example of DC-error calculations, using the
MAX4258 typical data and the typical operating circuit
with RF = RG = 510Ω (RF || RG = 255Ω) and RS = 50Ω,
gives:
VOUT = [1 x 10-3 x (1 + 1)] + [2 x 10-6 x 50 x (1 + 1)] +
[2 x 10-6 x 510]
VOUT = 3.22mV
12
RF
IB
IN_
RS
MAX4158
MAX4159
MAX4258
MAX4259
Figure 2. Output Offset Voltage
______________________________________________________________________________________
350MHz/250MHz, 2-Channel
Video Multiplexer-Amplifiers
RF
RG
RF
FB
OUT
75Ω CABLE
RT
75Ω
75Ω CABLE
INO
RT
75Ω
FB
INI
OUT
RT
75Ω
RISO
CL
IN_
RL
75Ω CABLE
MAX4158
MAX4159
MAX4258
MAX4259
RT
75Ω
Figure 3. Video Line Driver
MAX4158
MAX4159
MAX4258
MAX4259
Figure 4. Using an Isolation Resistor (RISO) for High
Capacitive Loads
Driving Capacitive Loads
A correctly terminated transmission line is purely resistive and presents no capacitive load to the amplifier.
Consequently, the MAX4158/MAX4159/MAX4258/
MAX4259 are optimized for AC performance and are
not designed to drive highly capacitive loads. Reactive
loads will decrease phase margin and may produce
excessive ringing and oscillation (see Typical
Operating Characteristics ). The circuit of Figure 4
reduces this problem. The small (usually 5Ω to 20Ω)
isolation resistor RISO, placed before the reactive load,
prevents ringing and oscillation. At higher capacitive
loads, AC performance is limited by the interaction of
load capacitance with the isolation resistor.
______________________________________________________________________________________
13
MAX4158/MAX4159/MAX4258/MAX4259
RG
MAX4158/MAX4159/MAX4258/MAX4259
350MHz/250MHz, 2-Channel
Video Multiplexer-Amplifiers
Input Voltage Range
the MAX4159/MAX4259. If power is first applied with
the latch enabled, IN0 is selected.
Input capacitance is a constant, low 2pF for either input
channel, regardless of whether or not the channel is
selected.
All logic levels (EN, LE, and A0) default low if left opencircuit.
The guaranteed input voltage range is ±2.5V. Exceeding
this value can cause unpredictable results, including output clipping, excessive input current, and switching
delays.
Multiplexer
The input multiplexer (mux) is controlled by TTL/CMOScompatible address inputs (see Truth Tables.) There is
no internal memory except the address latch (LE) on
ADDRESSING TIMES
A0
tS
tH
LE
tLPD
tSW
tLPW
OUT
ENABLE/DISABLE TIMES
EN
tPdD
tPdE
HIGH IMPEDANCE
OUT
Figure 5. Switching Timing Diagram
14
______________________________________________________________________________________
350MHz/250MHz, 2-Channel
Video Multiplexer-Amplifiers
TOP VIEW
MAX4159/MAX4259
EN 1
GND 2
LOGIC
MAX4159/MAX4259
14 LE
EN 1
13 A0
GND 2
IN0 3
12 OUT
IN0 3
GND 4
11 V+
GND 4
IN1 5
10 GND
16 LE
LOGIC
15 N.C.
14 A0
13 OUT
IN1 5
12 V+
GND 6
9
FB
GND 6
11 GND
V- 7
8
GND
N.C. 7
10 FB
V- 8
9
GND
SO
QSOP
MAX4159/MAX4259
MAX4159/MAX4259
LE
A0
INPUT
EN
OUTPUT
0
0
IN0
0
ON
1
OFF (HI-Z)
0
1
IN1
1
X
LAST
X = DON’T CARE
N.C. = NOT INTERNALLY CONNECTED
___________________Chip Information
TRANSISTOR COUNT: 239
______________________________________________________________________________________
15
MAX4158/MAX4159/MAX4258/MAX4259
_____________________Pin Configurations/Functional Diagrams/Truth Tables
8LUMAXD.EPS
________________________________________________________Package Information
QSOP.EPS
MAX4158/MAX4159/MAX4258/MAX4259
350MHz/250MHz, 2-Channel
Video Multiplexer-Amplifiers
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.
16 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2001 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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