MAX4028EUE+ Maxim Integrated Products, MAX4028EUE+ Datasheet - Page 10

• Manufacturer Part Number: MAX4028EUE+
• Description: IC AMP VIDEO MUX 2:1 16-TSSOP
• Manufacturer: Maxim Integrated Products

Specifications of MAX4028EUE+

• Applications: 2:1 Multiplexer-Amplifier
• Number Of Circuits: 3
• -3db Bandwidth: 210MHz
• Slew Rate: 300 V/µs
• Current - Supply: 29mA
• Current - Output / Channel: 30mA
• Voltage - Supply, Single/dual (±): 4.5 V ~ 5.5 V
• Mounting Type: Surface Mount
• Package / Case: 16-TSSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Although the MAX4028/MAX4029 are optimized for AC
performance and are not designed to drive highly
capacitive loads, they are capable of driving up to
15pF without oscillations. However, some peaking may
occur in the frequency domain (Figure 4). To drive larg-
er capacitive loads or to reduce ringing, add an isola-
tion resistor between the amplifier’s output and the load
(Figure 5). The value of R
Triple/Quad, 2:1 Video
Multiplexer-Amplifiers with Input Clamps
Figure 4. Small-Signal Gain vs. Frequency with Capacitive
Load and No Isolation Resistor
Figure 5. Using an Isolation Resistor (R ISO ) for a High-
Capacitive Load
10
75Ω CABLE
75Ω CABLE
R
______________________________________________________________________________________
KEYREF
75Ω
75Ω
R
R
T
T
11
10
9
8
7
6
5
4
3
2
1
100k
0.1µF
0.1µF
SMALL-SIGNAL BANDWIDTH
IN_A
IN_B
A/B
1M
CLAMP
vs. FREQUENCY
FREQUENCY (Hz)
MAX4028
MAX4029
C
C
LOAD
LOAD
10M
ISO
C
DISABLE
= 10pF
= 15pF
LOAD
depends on the circuit’s
= 5pF
OUT_
100M
R
ISO
1G
C
L
R
L
gain (+2V/V) and the capacitive load (Figure 6). Also
note that the isolation resistor forms a divider that
decreases the voltage delivered to the load.
The MAX4028/MAX4029 have high bandwidths and
consequently require careful board layout, including
the possible use of constant-impedance microstrip or
stripline techniques.
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. Whether or not a constant-imped-
ance board is used, it is best to observe the following
guidelines when designing the board:
1) Do not use wire-wrapped boards or breadboards.
2) Do not use IC sockets; they increase parasitic
3) Keep signal lines as short and straight as possible.
4) Observe high-frequency bypassing techniques to
5) Use surface-mount components. They generally
Figure 6. Optimal Isolation Resistance vs. Capacitive Load
capacitance and inductance.
Do not make 90° turns; round all corners.
maintain the amplifier’s accuracy and stability.
have shorter bodies and lower parasitic reactance,
yielding better high-frequency performance than
through-hole components.
Layout and Power-Supply Bypassing
30
25
20
15
10
5
0
0
OPTIMAL ISOLATION RESISTANCE
50
vs. CAPACITIVE LOAD
100
C
LOAD
(pF)
150
200
250