Texas Instruments TMS3637P, Data Manual

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6–2
The input to the internal comparator has a voltage swing of approximately 1.4 V peak-to-peak (13
×
108 mV).
OUT on the receiver maintains the same status for approximately 0.5 s (1M
×
470 nF).
Table 6–1. Two-Wire Direct Connection
DEVICE FUNCTION
U1 TMS3637 configured as a normal continuous logic transmitter
U2 TMS3637 configured as a analog normal Q-state noninverting receiver
R1 Pullup resistor on OUT, an open drain
R2 Resistor on OSCR that, in conjunction with C1, determines the internal oscillator frequency of U1.
R3 Resistor that provides current limiting and isolation between VCC and transmitter OUT swing.
R4 Upper portion of voltage divider used to bias receiver output
R5 Lower portion of voltage divider used to bias receiver output
R6 Resistor that is part of RC low-pass network on front end of U2 receiver
R7 Resistor on TIME that, along with C5, determines OUT pulse duration on U2.
R8 Resistor on OSCR that, in conjunction with C7, determines internal oscillator frequency on U2.
R9 Current-limiting resistor for LED indicator
C1 Capacitor on OSCC that, in conjunction with R2, determines internal oscillator frequency of U1.
C2 AC-coupling capacitor for output logic pulses from U1
C3 Power-supply bypass capacitor
C4 Capacitor that is part of RC low-pass network used on front-end of U2 receiver.
C5 Capacitor on TIME that, in conjunction with R7, determines OUT pulse duration on U2.
C6 Capacitor that sets gain of internal receive amplifier in U2.
C7 Capacitor on OSCC that, in conjunction with R8, determines internal oscillator frequency of U2.
D1 LED for indication of Q-state output toggling on and off