lmh6644mdc National Semiconductor Corporation, lmh6644mdc Datasheet - Page 18

• Manufacturer Part Number: lmh6644mdc
• Description: Low Power, 130mhz, 75ma Rail-to-rail Output Amplifiers
• Manufacturer: National Semiconductor Corporation

www.national.com
Application Notes
For this example, optimum C
be around 5pF. This time domain response is shown in
Figure 4 below showing about 9ns rise/fall times, corre-
sponding to about 39MHz for f
from the +5V supply is around 5mA with no load.
Ordering Information
FIGURE 4. Converter Step Response (1V
14-Pin TSSO
5-Pin SOT23
8-Pin MSOP
14-Pin SOIC
8-Pin SOIC
Package
LMH6643MMX
LMH6642MFX
LMH6642MAX
LMH6643MAX
LMH6644MAX
LMH6644MTX
Part Number
LMH6643MM
LMH6642MA
LMH6643MA
LMH6644MA
LMH6642MF
LMH6644MT
f
was empirically determined to
p
. The overall supply current
(Continued)
20018565
PP
, 20 ns/DIV)
Package Marking
LMH6642MA
LMH6643MA
LMH6644MA
LMH6644MT
A64A
A65A
18
PRINTED CIRCUIT BOARD LAYOUT AND COMPONENT
VALUES SECTION
Generally, a good high frequency layout will keep power
supply and ground traces away from the inverting input and
output pins. Parasitic capacitances on these nodes to
ground will cause frequency response peaking and possible
circuit oscillations (see Application Note OA-15 for more
information). National Semiconductor suggests the following
evaluation boards as a guide for high frequency layout and
as an aid in device testing and characterization:
These free evaluation boards are shipped when a device
sample request is placed with National Semiconductor.
Another important parameter in working with high speed/
high performance amplifiers, is the component values selec-
tion. Choosing external resistors that are large in value will
effect the closed loop behavior of the stage because of the
interaction of these resistors with parasitic capacitances.
These capacitors could be inherent to the device or a by-
product of the board layout and component placement. Ei-
ther way, keeping the resistor values lower, will diminish this
interaction to a large extent. On the other hand, choosing
very low value resistors could load down nodes and will
contribute to higher overall power dissipation.
Device
LMH6642MF
LMH6642MA
LMH6643MA
LMH6643MM
LMH6644MA
LMH6644MT
2.5k Units Tape and Reel
2.5k Units Tape and Reel
3.5k Units Tape and Reel
2.5k Units Tape and Reel
2.5k Units Tape and Reel
1k Units Tape and Reel
3k Units Tape and Reel
1k Units Tape and Reel
Transport Media
95 Units/Rail
95 Units/Rail
94 Units/Rail
55 units/Rail
Package
SOT23-5
8-Pin SOIC
8-Pin SOIC
8-Pin MSOP
14-Pin SOIC
14-Pin TSSOP
Evaluation
Board PN
CLC730216
CLC730227
CLC730036
CLC730123
CLC730231
CLC730131
NSC Drawing
MUA08A
MF05A
MTC14
M08A
M14A