HI-1573PSI Holt Integrated Circuits, HI-1573PSI Datasheet - Page 2

• Manufacturer Part Number: HI-1573PSI
• Manufacturer: Holt Integrated Circuits

Specifications of HI-1573PSI

• Operating Supply Voltage (typ): 3.3V
• Operating Supply Voltage (min): 3.15V
• Operating Supply Voltage (max): 3.45V
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 20
• Lead Free Status / RoHS Status: Not Compliant

PIN DESCRIPTIONS
FUNCTIONAL DESCRIPTION
The HI-1573 family of data bus transceivers contains dif-
ferential 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 inputs TXA/B and
transmitter accepts Manchester II bi-phase data and con-
verts 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 & SOIC)
/
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
TXA B
+3.3 volt power for transceiver 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 transceiver A
+3.3 volt power for transceiver 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 transceiver B
Receiver B output, inverted
Receiver B output, non-inverted
Transmit inhibit, bus 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, bus A. If high BUSA,
Transmitter A digital data input, non-inverted
Transmitter A digital data input, inverted
/ . The
BUSA B
/ are ei-
HI-1573, HI-1574
/
.
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 data at the RXA/B and
pins.
RXENB are high, RXA/B will be logic “0” on HI-1573 and
logic “1” on HI-1574.
Each set of receiver outputs can also be independently
forced to the bus idle state (logic "0” on HI-1573 or logic “1”
on HI-1574) 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.
When the MIL-STD-1553 bus is idle and RXENA or
DESCRIPTION
BUSA
BUSB
RXA
RXB
disabled
disabled
low (HI-1573) or High (HI-1574)
low (HI-1573) or High (HI-1574)
RXA B
/ output