PACSZ1284 Datasheet, PDF (5/11 Pages) California Micro Devices Corp – P/ACTIVE IEEE 1284 ECP/EPP TERMINATION NETWORK

PACSZ1284
Performance Information
Filter Capacitors
The IEEE 1284 specification requires both termination and EMI filtering on a total of 17 lines. Basic filtering is
provided through the presence of a capacitor on all signal lines. The filter capacitor is the junction capacitance
of an ESD diode. The typical capacitance at a reverse voltage of 2.5V is 150pF. This diode capacitance is
somewhat voltage dependent. See Figure .
Figure 1. Diode Capacitance vs. Reverse Voltage
The higher speed Data and Strobe lines (9 in total) require an additional series resistor termination for proper
operation, while the eight (8) Status lines do not. See Table 1.
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