Parameter Measurement Information (Continued)
DS011910-9
FIGURE 7. Receiver SHUTDOWN (SD) Delay Test Circuit
DS011910-10
FIGURE 8. Receiver SHUTDOWN (SD) Delay Timing
Pin Descriptions
VCC (Pin 3). Power supply pin for the device, +5V ( 0.5V).
±
ROUT 1–5 (Pins 10, 11, 12, 13, 14). Receiver output pins.
V+ (Pin 1). Positive supply for EIA/TIA-232-E drivers. Rec-
ommended external capacitor — 0.1 µF (16V). This supply is
not intended to be loaded externally.
GND (Pins 5, 27). Ground Pins. Both pins must be con-
nected to external ground. These pins are not connected to-
gether on the chip.
V− (Pin 25). Negative supply for EIA/TIA-232-E drivers. Rec-
ommended external capacitor — 0.1 µF (16V). This supply is
not intended to be loaded externally.
Application Information
In
a typical Data Terminal Equipment (DTE) to Data
C1+, C1− (Pins 2, 4). External capacitor connection pins.
C2+, C2− (Pins 28, 26). External capacitor connection pins.
Circuit-Terminating Equipment (DCE) 9-pin de-facto inter-
face implementation, 2 data lines and 6 control lines are re-
quired. The data lines are TXD and RXD and the control
lines are RTS, DTR, DSR, DCD, CTS and RI. The
DS14C535 is a 3 x 5 Driver/Receiver and offers a single chip
solution for the DTE interface as shown in Figure 9 .
SHUTDOWN (SD) (Pin 23). A High on the SHUTDOWN pin
will lower the total ICC current to less than 10 µA, providing a
low power state. In this mode receiver R5 remains active.
The SD pin should be driven or tied low (GND) to disable the
shutdown mode.
Ring Indicator (RI) is used to inform the DTE that an incom-
ing call is coming from a remote DCE. When the DS14C535
is in SHUTDOWN (SD) mode, receiver five (R5) remains ac-
tive and monitors RI circuit. This active receiver (R5) alerts
the DTE to switch the DS14C535 from SHUTDOWN to ac-
tive mode.
DIN 1–3 (Pins 7, 8, 9). Driver input pins.
DOUT 1–3 (Pins 22, 21, 20). Driver output pins conform to
EIA/TlA-232 -E levels.
RIN 1–5 (Pins 19, 18, 17, 16, 15). Receiver input pins accept
±
EIA/TIA-232-E input voltages ( 25V). Receivers guarantees
hysteresis of TBD mV. Unused receiver input pins may be
left open. Internal input resistor (5 kΩ) pulls input LOW, pro-
viding a failsafe HIGH output.
To achieve minimum power consumption, the DS14C535
can be in SHUTDOWN mode and only activated when com-
munications are needed.
5
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