HI-1567CDT HOLTIC [Holt Integrated Circuits], HI-1567CDT Datasheet - Page 2

• Manufacturer Part Number: HI-1567CDT
• Description: 5V Monolithic Dual Transceivers
• Manufacturer: HOLTIC [Holt Integrated Circuits]

PIN DESCRIPTIONS
FUNCTIONAL DESCRIPTION
The HI-1567 family of data bus transceivers contain differ-
ential voltage source drivers and differential receivers.
They are intended for applications using a MIL-STD-1553
A/B data bus. The device produces a trapezoidal output
waveform during transmission.
TRANSMITTER
Data input to the device’s transmitter section is from the
complementary CMOS /TTL inputs TXA/B and
The transmitter accepts Manchester II bi-phase data and
converts it to differential voltages on
The transceiver outputs are either direct or transformer
coupled to the MIL-STD-1553 data bus. Both coupling
methods produce a nominal voltage on the bus of 7.5 volts
peak to peak.
The transmitter is automatically inhibited and placed in the
high impedance state when both TXA/B and
ther at a logic “1” or logic “0” simultaneously. A logic “1” ap-
plied to the TXINHA/B input will force the transmitter to the
high impedance state, regardless of the state of TXA/B and
TXA B.
(DIP/ESOIC)
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PIN
10
11
12
13
14
15
16
17
18
19
20
1
2
3
4
5
6
7
8
9
SYMBOL
TXINHB
TXINHA
RXENA
RXENB
GNDA
GNDB
VDDA
BUSA
BUSA
VDDB
BUSB
BUSB
RXB
RXB
RXA
RXA
TXB
TXB
TXA
TXA
analog output
analog output
analog output
analog output
power supply
power supply
power supply
power supply
FUNCTION
digital output
digital output
digital output
digital output
digital input
digital input
digital input
digital input
digital input
digital input
digital input
digital input
BUSA/B and
HOLT INTEGRATED CIRCUITS
TXA B
+5 volt power for channel A
MIL-STD-1533 bus driver A, positive signal
MIL-STD-1553 bus driver A, negative signal
Receiver A enable. If low, forces RXA and
Ground for channel A
+5 volt power for channel B
MIL-STD-1533 bus driver B, positive signal
MIL-STD-1553 bus driver B, negative signal
Receiver B enable. If low, forces RXB and
Ground for channel B
Receiver B output, inverted
Receiver B output, non-inverted
Transmit inhibit, channel B. If high BUSB,
Transmitter B digital data input, non-inverted
Transmitter B digital data input, inverted
Receiver A output, inverted
Receiver A output, non-inverted
Transmit inhibit, channel A. If high BUSA,
Transmitter A digital data input, non-inverted
Transmitter A digital data input, inverted
BUSA B
/ are ei-
HI-1567, HI-1568
TXA B
/ .
/
.
2
RECEIVER
The receiver accepts bi-phase differential data from the
MIL-STD-1553 bus through the same direct or transformer
coupled interface as the transmitter. The receiver’s differ-
ential input stage drives a filter and threshold comparator
that produces CMOS/TTL data at the RXA/B and
output pins.
Each set of receiver outputs can be independently forced
to a logic "0" (HI-1567) or logic “1” (HI-1568) by setting
RXENA or RXENB low.
MIL-STD-1553 BUS INTERFACE
A direct coupled interface (see Figure 2) uses a 1:2.5 ratio
isolation transformer and two 55 ohm isolation resistors
between the transformer and the bus.
In a transformer coupled interface (see Figure 3), the
transceiver is connected to a 1:1.79 isolation transformer
which in turn is connected to a 1:1.4 coupling transformer.
The transformer coupled method also requires two
coupling resistors equal to 75% of the bus characteristic
impedence (Zo) between the coupling transformer and the
bus.
DESCRIPTION
BUSA
BUSB
RXA
RXB
low (HI-1567) or High (HI-1568)
low (HI-1567) or High (HI-1568)
disabled
disabled
RXA B
/