THS3201 Datasheet, PDF (21/29 Pages) Texas Instruments – 1.8-GHz, LOW DISTORTION, CURRENT FEEDBACK AMPLIFIER

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For systems where heat dissipation is more critical, the
THS3201 is offered in an 8-pin MSOP with PowerPAD and
the THS3201 is available in the SOIC−8 PowerPAD
package offering even better thermal performance. The
thermal coefficient for the PowerPAD packages are
substantially improved over the traditional SOIC.
Maximum power dissipation levels are depicted in the
graph for the available packages. The data for the
PowerPAD packages assume a board layout that follows
the PowerPAD layout guidelines referenced above and
detailed in the PowerPAD application note number
SLMA002. The following graph also illustrates the effect of
not soldering the PowerPAD to a PCB. The thermal
impedance increases substantially which may cause
serious heat and performance issues. Be sure to always
solder the PowerPAD to the PCB for optimum
performance.
4.0
TJ = 125°C
3.5
3.0
θ_JA = 58.4°C/W
2.5
θ_JA = 98°C/W
2.0
1.5
1.0
0.5
θ_JA = 158°C/W
0.0
−40 −20 0 20 40 60 80 100
TA − Free-Air Temperature − °C
Results are With No Air Flow and PCB Size = 3”x3”
θ_JA = 58.4°C/W for 8-Pin MSOP w/PowerPad (DGN)
θ_JA = 98°C/W for 8-Pin SOIC High Test PCB (D)
θ_JA = 158°C/W for 8-Pin MSOP w/PowerPad w/o Solder
Figure 63. Maximum Power Dissipation vs
Ambient Temperature
When determining whether or not the device satisfies the
maximum power dissipation requirement, it is important to
not only consider quiescent power dissipation, but also
dynamic power dissipation. Often times, this is difficult to
THS3201
SLOS416A − JUNE 2003 − REVISED JANUARY 2004
quantify because the signal pattern is inconsistent, but an
estimate of the RMS power dissipation can provide
visibility into a possible problem.
DESIGN TOOLS
Evaluation Fixture, Spice Models, and
Applications Support
Texas Instruments is committed to providing its customers
with the highest quality of applications support. To support
this goal an evaluation board has been developed for the
THS3201 operational amplifier. The board is easy to use,
allowing for straightforward evaluation of the device. The
evaluation board can be ordered through the Texas
Instruments web site, www.ti.com, or through your local
Texas Instruments sales representative. The schematic
diagram, board layers, and bill of materials of the
evaluation boards are provided below.
PD
J9*
J1
Vin−
0Ω
R3
768 Ω
R2
J2
Vin+
49.9 Ω ^R4
C8*
R5
Vs+ 768 Ω
7 8 _U1
2_{_}
6
3₊
41
R6
49.9 Ω
Vs −
J8*
PD Ref
J4
R7
Vout
Not Populated
C7*
*Does Not Apply to the THS3201
J6
GND TP1
J7
VS−
VS−
FB1
C1
C6
+ 22 µF _{0.1 µF}
C5
100 pF
J5
VS+
VS+
FB2
C4
C3
100 pF 0.1 µF
+
C2
22 µF
Figure 64. THS3201 EVM Circuit Configuration
21