LMH6553SDE/NOPB National Semiconductor, LMH6553SDE/NOPB Datasheet - Page 18

• Manufacturer Part Number: LMH6553SDE/NOPB
• Description: IC AMP DIFF 900MHZ W/CLAMP 8LLP
• Manufacturer: National Semiconductor
• Series: LMH®, PowerWise®r

Specifications of LMH6553SDE/NOPB

• Amplifier Type: Differential
• Number Of Circuits: 1
• Output Type: Differential
• Slew Rate: 2300 V/µs
• -3db Bandwidth: 900MHz
• Current - Input Bias: 50µA
• Current - Supply: 29.1mA
• Current - Output / Channel: 120mA
• Voltage - Supply, Single/dual (±): 4.5 V ~ 12 V, ±2.25 V ~ 6 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-LLP
• No. Of Amplifiers: 1
• Bandwidth: 900MHz
• Supply Voltage Range: 4.5V To 12V
• Supply Current: 29.1mA
• Amplifier Case Style: LLP
• No. Of Pins: 8
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Gain Bandwidth Product: -
• Voltage - Input Offset: -
• Other names: *LMH6553SDE/NOPB; LMH6553SDETR

www.national.com
When using the LMH6553 in single-to-differential mode, the
complementary output is forced to a phase inverted replica of
the driven output by the common mode feedback circuit as
opposed to being driven by its own complementary input.
Consequently, as the driven input changes, the common
mode feedback action results in a varying common mode
voltage at the amplifier's inputs, proportional to the driving
signal. Due to the non-ideal common mode rejection of the
amplifier's input stage, a small common mode signal appears
at the outputs which is superimposed on the differential output
signal. The ratio of the change in output common mode volt-
age to output differential voltage is commonly referred to as
output balance error. The output balance error response of
the LMH6553 over frequency is shown in the Typical Perfor-
mance Characteristics section.
To match the input impedance of the circuit in
specified source resistance, R
The equations governing R
operation are also provided in
along with the source matching condition, must be solved it-
eratively to achieve the desired gain with the proper input
termination. Component values for several common gain con-
figurations in a 50Ω environment are given in
FIGURE 3. Single-Ended Input with Differential Output
12 dB
TABLE 1. Gain Component Values for 50Ω System
TABLE 2. Gain Component Values for 50Ω System
12 dB
Gain
Gain
0 dB
6 dB
0 dB
6 dB
275Ω
275Ω
275Ω
325Ω
325Ω
325Ω
R
R
F
F
PSOP Package
LLP Package
54.9Ω
255Ω
127Ω
68.1Ω
IN
316Ω
150Ω
R
R
and A
G
S
G
, requires that R
Figure
V
for single-to-differential
68.1Ω
107Ω
56.2Ω
64.9Ω
88.7Ω
3. These equations,
59Ω
R
R
T
T
Table
Figure 3
T
|| R
26.7Ω
28.7Ω
26.7Ω
31.6Ω
1.
34Ω
28Ω
IN
R
R
30043710
M
M
= R
to a
S
.
18
The circuit shown in
eters for a single-to-differential configuration. The S-parame-
ter plots in the Typical Performance Curves are taken using
the recommended component values for 0 dB gain.
SINGLE SUPPLY OPERATION
Single supply operation is possible on supplies from 5V to
10V; however, as discussed earlier, AC input coupling is rec-
ommended for low supplies due to input common mode limi-
tations. An example of an AC coupled, single supply, single-
to-differential circuit is shown in
coupling, both inputs need to be AC coupled irrespective of
single-to-differential or differential-to-differential configura-
tion. For higher supply voltages, DC coupling of the inputs
may be possible provided that the output common mode DC
level is set high enough so that the amplifier's inputs and out-
puts are within their specified operating ranges.
FIGURE 4. Single Ended Input S-Parameter Test Circuit
FIGURE 5. AC Coupled for Single Supply Operation
Figure 4
(50Ω System)
was used to measure S-param-
Figure
5. Note that when AC
30043709
30043754