GS1528 Data Sheet
3.5 Output Amplitude Adjustment
The output amplitude of the GS1528 can be adjusted by changing the value of the
resistor as shown in Figure 3-4 and Table 3-1: RSET vs VOD. For an
R
SET
800mV output with a nominal ±7% tolerance, a value of 750Ω is required. A ±1%
p-p
SMT resistor should be used.
1100
1000
900
800
700
600
500
600
700
SET
800
900
1000
R
R (Ω)
Figure 3-4: Output Amplitude Adjustment
The R
resistor is part of the high speed output circuit of the GS1528. The
SET
resistor should be placed as close as possible to the R
pin. In addition, the PCB
SET
capacitance should be minimized at this node by removing the PCB groundplane
beneath the R resistor and the R pin.
SET
SET
Table 3-1: RSET vs VOD
RSET R (Ω)
Output Swing
995
824
750
600
573
608
734
800
884
1040
NOTE: For reliable operation of the GS1528 over the full temperature range, do not
use an RSET value below 573Ω.
16632 - 5 June 2005
10 of 13
GENNUM [ GENNUM CORPORATION ]
