mc14c89b ON Semiconductor, mc14c89b Datasheet - Page 6

• Manufacturer Part Number: mc14c89b
• Description: Quad Low Power Line Receivers
• Manufacturer: ON Semiconductor

Description
replacements for the MC1489A and MC1489. Both devices meet all
EIA−232 specifications and also the faster EIA−562 and CCITT V.28
specifications. Noise pulse rejection circuitry eliminates the need for
most response control filter capacitors but does not exclude the
possibility as filtering is still possible at the Response Control (RC)
pins. Also, the Response Control pins allow for a user defined
selection of the threshold voltages. The MC14C89AB and
MC14C89B are manufactured with a bipolar technology using low
power techniques and consume at most 700 mA, plus load currents
with a +5.0 V supply.
Outputs
the load current, the bias of the Response Control pins, and the supply
voltage. Table 1 applies to each receiver, regardless of how many other
receivers within the package are supplying load current.
Receiver Inputs and Response Control
accordance with Table 1. The nominal V
0.95 V and 1.90 V respectively for the MC14C89AB. For the
MC14C89B, the nominal V
respectively. The inputs are able to withstand ±30 V referenced to
ground. Should the input voltage exceed ground by more than ± 30 V,
excessive currents will flow at the input pin. Open input pins will
generate a logic high output, but good design practices dictate that
inputs should never be left open.
resistor string. The RC pins provide for adjustment of the threshold
voltages of the IC while preserving the amount of hysteresis. Figure 10
shows a typical application to adjust the threshold voltages. The RC
pins also provide access to an internal resistor string which permits
low pass filtering of the input signal within the IC. Like the input pins,
the RC pins should not be taken above or below ground by more than
± 30 V or excessive currents will flow at these pins. The dependence of
the low level threshold voltage (V
described by the following equation:
V
The MC14C89AB and MC14C89B are designed to be direct
The output low or high voltage depends on the state of the inputs,
The receiver inputs determine the state of the outputs in
The Response Control (RC) pins are coupled to the inputs through a
IL
]
5.32 kW ) 6.67
V 0.09 * V
*The asterisk denotes A, B, C, or D.
Table 1. Function Table
Input*
505 W
H
L
bat
R
Receivers
RC
10 6 W 2
R
IL
RC
and V
(1.6) ) 2.02 kW
Output*
505 W
IL
IH
H
L
) upon R
thresholds are 0.95 and 1.30,
IL
APPLICATIONS INFORMATION
and V
RC
http://onsemi.com
IH
and V
thresholds are
(1)
bat
6
can be