Document
CT1990/1 Series
MIL-STD-1553B Remote Terminal, Bus Controller, or Passive Monitor Hybrid with Status Word Control
Features
• Performs the Complete Dual-Redundant Remote Terminal, Bus Controller Protocol and Passive Monitor Functions of MIL-STD-1553B • Automated Self-Test Functions • Allows setting of the Message Error Bit on illegal commands • Provides programmable control over Terminal Flag and Subsystem Flag Status Bits • MIL-PRF-38534 Compliant Circuits Available • 50 mw Typical Power Consumption • Small Size • Available in Ceramic Plug-in Package Configuration CIRCUIT TECHNOLOGY • Compatible with all ACT Driver/Receiver Units • 5V DC Operation • Full Military (-55°C to +125°C) Temperature Range • DESC SMD# 5962–94775: Released CT1990, Pending CT1991
1
General Description
The CT1990/1 Series is a monolithic implementation of the MIL-STD-1553B Bus Controller, Remote Terminal and Passive Monitor functions. All protocol functions of MIL-STD-1553B are incorporated and a number of options are included to improve flexibility. These features include programming of the status word, illegalizing specific commands and an independent loop back self-test which is initiated by the subsystem. This unit is directly compatible with all transceivers and microprocessor interfaces such as the CT1611 and CT1800 produced by Aeroflex Incorporated. Block Diagram (With Transformers)
Encoder
Interface Unit
Sub Address & Word Count Outputs
BUS "0"
T/R Hybrid Driver Select & Enable T/R Hybrid
Decoder "O"
Status Word Control
Program Inputs
Discrete Outputs
BUS "1"
Decoder "1"
Internal Highway Control
Control Inputs
Terminal Address Inputs
CT1990/1
eroflex Circuit Technology – Data Bus Modules For The Future © SCD1990 REV B 8/21/00
Absolute Maximum Ratings
Parameter
Supply Voltage (VDD) Input or Output Voltage at any Pad Storage Case Temperature
Range
-0.3 to +7.0 -0.3 to (VDD + 0.3) -65 to +150
Units
V V °C
Recommended DC Operating Conditions
Parameter
Vcc Power Supply Voltage Vcc VIH High Level Input Voltage, Vcc = 5V VIL Low Level Input Voltage, Vcc = 5V
Min
4.5 2.2
Typ
5.0
Max
5.5
Unit
V V
Notes
1,2 1,2
0.7
V
Electrical Characteristics
(TA = -55°C to +125°C)
Parameter
VOH High Level Output Voltage VOL Low Level Output Voltage IIH High Level Input Current
Test Conditions
Vcc = 4.5V Vcc = 4.5V Vcc = 5.5V, VIN = 2.4V
Min
2.4
Max
Unit
V
Notes
4 4 2 3 2 3 4
0.4 -200 -25 -700 -400 -900 -400 20
V µA µA µA µA mA
IIL Low Level Input Current
Vcc = 5.5V, VIN = 0.4V
-400 -25
ICC Supply Current
Vcc = 5.5V
Notes: 1. RTAD 0/1/2/3/4 and RTADPAR ONLY. 2. ALL Inputs and Bidirectionals other than those in Note 1. 3. lOL max = 3mA / lOH max = -2mA TX INHIBIT 0/1 and TX DATA/DATA ONLY. IOL max = 2mA / lOH max = -1 mA. ALL remaining Outputs and Bidirectionals. 4. Input Clock (running) = 6Mhz, ALL remaining Inputs are Open and ALL Outputs and Bidirectionals have no load.
Clock Requirements
Frequency Stability -55°C to +125°C Maximum Asymmetry Rise/Fall Time Output Level 6.0 MHz ±0.01% (100ppm) 48 - 52% 10ns MAX Logic "0" 0.4V MAX Logic "1" 2.4V MIN
Aeroflex Circuit Technology
2
SCDCT1990 REV B 8/21/00 Plainview NY (516) 694-6700
REMOTE TERMINAL OPERATION
Receive Data Operation
All valid data words associated with a valid receive data command word for the RT are passed to the subsystem. The RT examines all command words from the bus and will respond to valid (i.e. correct Manchester, parity coding etc.) commands which have the correct RT address (or broadcast address if the RT broadcast option is enabled). When the data words are received, they are decoded and checked by the RT and, if valid, passed to the subsystem on a word by word basis at 20 µs intervals. This applies to receive data words in both Bus Controller to RT and RT to RT messages. When the RT detects that the message has finished, it checks that the correct number of words have been received and if the message is fully valid, then a Good Block Received signal is sent to the subsystem, which must be used by the subsystem as permission to use the data just received. The subsystem must therefore have a temporary buffer store up to 32 words long into which these data words can be placed. The Good Block Received signal will allow use of the buffer store data once the message has been validated. If a block of data is not validated, then Good Block Received will not be generated. This may be caused by any sort of message error or by a new valid command for the RT being received on another bus to which the RT must switch.
Transmit Data Operation
If the RT receives a valid transmit data command addressed to the RT, then the RT will request the data words from the subsystem for transmission on a word by word basis. To allow maximum time for the subsystem to collect each data word, the next word is requested by the RT as soon as the transmission of the current word has commenced. It is essential that the subsystem should provide all the data words req.