RHF1201 STMICROELECTRONICS [STMicroelectronics], RHF1201 Datasheet - Page 11

• Manufacturer Part Number: RHF1201
• Description: Rad-hard 12-bit 0.5 to 50 Msps A/D converter
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

RHF1201
7.2.2
7.2.3
Figure 4.
Single-ended input configuration
Some applications may require a single-ended input which is easily achieved with the
configuration shown in
The lack of accurate differential driving with its common-mode noise and even harmonics
cancellation advantages can degrade the rated RHF1201 performance. It is then
recommended to use a well de-coupled DC reference to bias the RHF1201 inputs.
In this case, one can use an AC-coupled analog input and set the DC analog level with high
value (10 kΩ to 100 kΩ) resistor connected to a proper DC source.
The internal references INCM (0.52 V) or REFP (1 V) can be used as proper DC sources.
Using 1 V DC with a single signal of 2 V
Figure 5.
IF-sampling
The RHF1201 is specifically designed to meet sampling requirements for intermediate
frequency input signals. In particular, the Track-and-Hold in the first stage of the pipeline is
designed to minimize the linearity limitations as analog frequency increases.This is
achieved by making the input impedance independent from the input frequency.
As a result, the RHF1201 can maintain high performance up to an analog frequency of
150 MHz.
Differential input configuration
Single-ended input configuration
Figure 5: Single-ended input
Signal source
Analog source
50Ω
50Ω
10-100kΩ
ADT1-1
1:1
330pF
pp
10nF
330pF
input amplitude gives better SNR performance.
10-100pF
VINB
VIN
10nF
RHF1201
configuration.
10nF
470nF
VINB
VIN
RHF1201
470nF
INCM
DC source or REFP
Application information
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