LMH6654 Datasheet, PDF (12/17 Pages) National Semiconductor (TI) – Single/Dual Low Power, 250 MHz, Low Noise Amplifiers

Connection Diagrams
LMH6654 in SOIC
LMH6654 in SOT23-5
LMH6655 in SOIC and MSOP
20016521
Top View
20016520
Top View
20016519
Top View
Ordering Information
Package
8-Pin SOIC
5-Pin SOT23-5
8-Pin MSOP
Part Number
LMH6654MA
LMH6654MAX
LMH6655MA
LMH6655MAX
LMH6654MF
LMH6654MFX
LMH6655MM
LMH6655MMX
Package Marking
LMH6654MA
LMH6655MA
A66A
A67A
Transport Media
95 Units Rails
2.5k Units Tape and Reel
95 Units Rails
2.5k Units Tape and Reel
1k Units Tape and Reel
3K Units Tape and Reel
1k Units Tape and Reel
3.5k Units Tape and Reel
NSC Drawing
M08A
MF05A
MUA08A
Application Information
General Information
The LMH6654 single and LMH6655 dual high speed, voltage
feedback amplifiers are manufactured on National Semicon-
ductor’s new VIP10 (Vertically Integrated PNP) complemen-
tary bipolar process. These amplifiers can operate from
±2.5V to ±6V power supply. They offer low supply current,
wide bandwidth, very low voltage noise and large output
swing. Many of the typical performance plots found in the
datasheet can be reproduced if 50Ω coax and 50Ω R_IN/_ROUT
resistors are used.
Circuit Layout Consideration
With all high frequency devices, board layouts with stray
capacitance have a strong influence on the AC performance.
The LMH6654/55 are not exception and the inverting input
and output pins are particularly sensitive to the coupling of
parasitic capacitance to AC ground. Parasitic capacitances
on the inverting input and output nodes to ground could
cause frequency response peaking and possible circuit os-
cillation. Therefore, the power supply, ground traces and
ground plan should be placed away from the inverting input
and output pins. Also, it is very important to keep the para-
sitic capacitance across the feedback to an absolute mini-
mum.
The PCB should have a ground plane covering all unused
portion of the component side of the board to provide a low
impedance path. All trace lengths should be minimized to
reduce series inductance.
Supply bypassing is required for the amplifiers performance.
The bypass capacitors provide a low impedance return cur-
rent path at the supply pins. They also provide high fre-
quency filtering on the power supply traces. It is recom-
mended that a ceramic decoupling capacitor 0.1µF chip
should be placed with one end connected to the ground
plane and the other side as close as possible to the power
pins. An additional 10µF tantalum electrolytic capacitor
should be connected in parallel, to supply current for fast
large signal changes at the output.
20016541
FIGURE 1.
Evaluation Boards
National provides the following evaluation boards as a guide
for high frequency layout and as an aid in device testing and
characterization.
Device
LMH6654MF
LMH6654MA
LMH6655MA
LMH6655MM
Package
SOT23-5
8-Pin SOIC
8-Pin SOIC
8-Pin MSOP
Evalulation
Board PN
CLC730068
CLC730027
CLC730036
CLC730123
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