Datasheet

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Optional Configuration: PGA870

Figure 8. FFT Plot: 200 MHz clock, 149 MHz input; SNRBOOST Enabled With Filter #40

3 Optional Configuration: PGA870

Channel D input (J9) can be configured to utilize the programmable gain op-amp, PGA870. The changes

required to modify the transformer coupled input to the OPA-driven input are shown in .

Table 2. Jumper Setting for Transformer-Coupled or OPA-Driven Input

Jumpers Transformer-Coupled Input OPA-Driven Input

SJP1 Shunt 1-2, default Shunt 3-2

SJP2 Shunt 1-2, default Shunt 3-2

SJP3 Shunt 3-2, option

SJP4 Shunt 1-2, default Shunt 3-2

JP16 Shunt 1-2

JP17 Shunt 1-2, default

JP18 Shunt 1-2, default

JP19 Shunt 1-2, default

Power is supplied to the device by applying 5 V to J2 and GND J3. By default the PGA870 is set as fixed

gain. There is gain control available through SW2, JP18 and JP19. An on-board layout option for a LPF or

BPF is available between the amplifier and the ADC. By default the filter is bypassed to allow the user

flexibility to design according to desired specifications.

SLAU313–May 2010 ADS58C48EVM