ADA4858-3ACPZ-R2 Analog Devices Inc, ADA4858-3ACPZ-R2 Datasheet - Page 14

• Manufacturer Part Number: ADA4858-3ACPZ-R2
• Description: IC, OP-AMP, 600MHZ, 600V/µs, LFCSP-16
• Manufacturer: Analog Devices Inc

Specifications of ADA4858-3ACPZ-R2

• Op Amp Type: High Speed
• No. Of Amplifiers: 3
• Bandwidth: 600MHz
• Slew Rate: 600V/µs
• Supply Voltage Range: 3V To 5.5V
• Amplifier Case Style: LFCSP
• No. Of Pins: 16
• Amplifier Type: Current Feedback
• Number Of Circuits: 3
• -3db Bandwidth: 600MHz
• Current - Input Bias: 8µA
• Voltage - Input Offset: 500µV
• Current - Supply: 19mA
• Current - Output / Channel: 21mA
• Voltage - Supply, Single/dual (±): 3 V ~ 5.5 V
• Operating Temperature: -40°C ~ 105°C
• Mounting Type: Surface Mount
• Package / Case: 16-LFCSP
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Output Type: -
• Gain Bandwidth Product: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

ADA4858-3
APPLICATIONS INFORMATION
GAIN CONFIGURATIONS
The ADA4858-3 is a single-supply, high speed, voltage feedback
amplifier. Table 5 provides a convenient reference for quickly
determining the feedback and gain set resistor values and band-
width for common gain configurations.
Table 5. Recommended Values and Frequency Performance
Gain
1
2
5
1
Figure 38 and Figure 39 show the typical noninverting and
inverting configurations and the recommended bypass
capacitor values.
DC-COUPLED VIDEO SIGNAL
The ADA4858-3 does not have a rail-to-rail output stage. The
output can be within 1 V of the rails. Having a charge pump on
board that can provide −3 V on a +5 V supply and −2 V on
+3.3 V supply makes this part excellent for video applications. In
dc-coupled applications, the black color has a 0 V voltage reference.
This means that the output voltage should be able to reach 0 V,
which is feasible with the presence of the charge pump. Figure 40
shows the schematic of a dc-coupled, single-supply application.
It is similar to the dual-supply application in which the input is
properly terminated with a 50 Ω resistor to ground. The amplifier
itself is set at a gain of 2 to account for the input termination loss.
Conditions: V
R
402
301
200
F
(Ω)
V
S
IN
= 5 V, T
Figure 38. Noninverting Gain Configuration
V
Figure 39. Inverting Gain Configuration
R
N/A
301
40
IN
R
G
A
G
(Ω)
= 25°C, R
R
G
+
ADA4858-3
–
R
–
ADA4858-3
+
Small Signal
−3 dB BW (MHz)
600
350
160
R
F
F
L
= 150 Ω.
+V
+V
S
S
0.1µF
10µF
0.1µF
10µF
Large Signal 0.1 dB
Flatness (MHz)
88
85
35
V
OUT
V
OUT
Rev. A | Page 14 of 20
1
The choice of R
maximum flatness vs. power dissipation trade-off. In this case, the
flatness is over 90 MHz, which is more than the high definition
video requirement.
MULTIPLE VIDEO DRIVER
In applications requiring that multiple video loads be driven
simultaneously, the ADA4858-3 can deliver 5 V supply operation.
Figure 41 shows the ADA4858-3 configured with two video
loads, and Figure 42 shows the two video load performances.
V
IN
Figure 42. Large Signal Frequency Response for Various Loads
6.5
6.0
5.5
5.0
4.5
4.0
3.5
3.0
2.5
CABLE
1
Figure 41. Video Driver Schematic for Two Video Loads
V
75Ω
301Ω
V
R
G = 2
V
IN
R
Figure 40. DC-Coupled, Single-Supply Schematic
S
F
OUT
G
= 5V
= 301Ω
75Ω
249Ω
R1
= 2V p-p
F
R2
and R
75Ω
–
ADA4858-3
+
G
249Ω
+
ADA4858-3
–
R3
+V
should be carefully considered for
10
10µF
C1
S
FREQUENCY (MHz)
U1
0.1µF
10µF
5V
–V
R
0.1µF
S
L
301Ω
C2
R
= 75Ω
F
75Ω
75Ω
100
R
75Ω
R4
L
CABLE
CABLE
= 150Ω
75Ω
75Ω
R5
75Ω
V
OUT
75Ω
75Ω
V
V
1000
OUT
OUT
1
2