Texas Instruments THS770006 Evaluation Module THS770006EVM THS770006EVM 데이터 시트
제품 코드
THS770006EVM
50W
50W
100W
V
OUT+
V
OUT-
100W
V
IN-
V
IN+
Differential
Output
Output
Differential
Input
THS770006
SBOS520B
–
JULY 2010
–
REVISED JANUARY 2012
THEORY OF OPERATION
GENERAL DESCRIPTION
The THS770006 is a fixed-gain of +6dB, wideband, fully-differential amplifier designed and optimized specifically
for driving 14-bit and 16-bit ADCs at input frequencies up to 200MHz. This device provides high bandwidth, low
distortion, and low noise, which are critical parameters in high-speed data acquisition systems that require very
high dynamic range, such as wireless base stations and test and measurement applications. It also makes an
excellent differential amplifier for general-purpose, high-speed differential signal chain and short line-driver
applications. The device has an operating power-supply range of 4.75V to 5.5V. The THS770006 has proprietary
circuitry to provide very fast recovery from overdrive conditions and has a power-down mode for power saving.
The THS770006 is offered in a Pb-free (RoHS compliant) and green, QFN-24 thermally-enhanced package. It is
characterized for operation over the industrial temperature range of
for driving 14-bit and 16-bit ADCs at input frequencies up to 200MHz. This device provides high bandwidth, low
distortion, and low noise, which are critical parameters in high-speed data acquisition systems that require very
high dynamic range, such as wireless base stations and test and measurement applications. It also makes an
excellent differential amplifier for general-purpose, high-speed differential signal chain and short line-driver
applications. The device has an operating power-supply range of 4.75V to 5.5V. The THS770006 has proprietary
circuitry to provide very fast recovery from overdrive conditions and has a power-down mode for power saving.
The THS770006 is offered in a Pb-free (RoHS compliant) and green, QFN-24 thermally-enhanced package. It is
characterized for operation over the industrial temperature range of
–
40
°
C to +85
°
C.
The amplifier uses two negative-feedback loops. One is for the primary differential amplifier and the other
controls the common-mode operation.
controls the common-mode operation.
Primary Differential Amplifier
The primary amplifier of the THS770006 is a fully-differential op amp with on-chip gain setting resistors (R
F
=
100
Ω
and R
G
= 50
Ω
) that fix the differential gain at 2V/V, or 6dB, by use of negative feedback.
V
OCM
Control Loop
The output common-mode voltage is controlled through a second negative-feedback loop. The output
common-mode voltage is internally sensed and compared to the V
common-mode voltage is internally sensed and compared to the V
OCM
pin. The loop then works to drive the
difference, or error voltage, to zero in order to maintain the output common-mode voltage = V
OCM
(within the loop
gain and bandwidth of the loop). For more details on fully-differential amplifier theory and use, see application
report
report
, Fully-Differential Amplifiers, available for download from www.ti.com.
OPERATION
Differential to Differential
The THS770006 is a fixed gain of 6dB, fully-differential amplifier that can be used to amplify differential input
signals to differential output signals. A basic block diagram of the circuit is shown in
signals to differential output signals. A basic block diagram of the circuit is shown in
. The differential
input to differential output configuration gives the best performance; the signal source and load should be
balanced.
balanced.
Figure 34. Differential Input to Differential Output Amplifier
18
Copyright
©
2010
–
2012, Texas Instruments Incorporated
Product Folder Link(s):