ISL59442_07 Datasheet, PDF (8/11 Pages) Intersil Corporation – 1GHz, 4 x 1 Multiplexing Amplifier

AC Test Circuits
V_IN
50Ω
or
75Ω
ISL59442
C_L
2pF
R_L
500Ω
ISL59442
ISL59442
R_S
V_IN
50Ω
C_L ^475Ω
50Ω
or
2pF
or
75Ω
75Ω
TEST EQUIPMENT
50Ω
or
75Ω
FIGURE 23A. TEST CIRCUIT WITH OPTIMAL OUTPUT LOAD
FIGURE 23B. TEST CIRCUIT FOR MEASURING WITH A 50Ω OR 75Ω
INPUT TERMINATED EQUIPMENT
V_IN
50Ω
or
75Ω
ISL59442
R_S
C_L ^{50Ω or 75Ω}
2pF
TEST EQUIPMENT
50Ω
or
75Ω
FIGURE 23C. BACKLOADED TEST CIRCUIT FOR VIDEO CABLE APPLICATION. BANDWIDTH AND LINEARITY FOR RL LESS THAN 500Ω WILL BE
DEGRADED
NOTE: Figure 23A illustrates the optimum output load for testing AC performance. Figure 23B illustrates the optimum output load when connecting
to input terminated equipment. Figure 23C illustrates back loaded test circuit for video cable.
Application Circuits
V_IN
50Ω
*C_L = C_T + C_OUT
-
V_OUT
+
C_T
1.6pF
C_OUT
0pF
R_L = 500Ω
*C_L: TOTAL LOAD CAPACITANCE
C_T: TRACE CAPACITANCE
C_OUT: OUTPUT CAPACITANCE
FIGURE 24A. SMALL SIGNAL 200mV_P-P APPLICATION CIRCUIT
V_IN
50Ω
R_S
-
25Ω
V_OUT
+
1.6pF ^CT
C_OUT
R_L = 500Ω
22pF
C_L = C_T + C_OUT
FIGURE 24B. LARGE SIGNAL 2V_P-P APPLICATION CIRCUIT
8
FN7452.4
January 5, 2007