ACT4438-1 - Aeroflex Microelectronic Solutions

Standard Products
ACT4438 Transceiver
for MIL-STD-1553 / 1760 in a Chipscale Package
www.aeroflex.com/AVIONICS
December 20, 2006
FEATURES
❑
Transceiver meets MIL-STD-1553 and MIL-STD-1760
❑
Low power dissipation at full output power
❑
Single +5V power supply
❑
Receiver threshold control
❑
Current Source Transmitter Output
❑
Bipolar Monolithic Construction
❑
Aeroflex is a Class H & K MIL-PRF-38534 Manufacturer
❑
Designed for commercial, industrial and aerospace applications
❑
Integral heat sink
❑
Miniature Chipscale Package: QFN, Epad, 52 lead, 8 x 8 mm
Weight: 0.2g
GENERAL DESCRIPTION
The Aeroflex Plainview Model ACT4438 is a next generation monolithic transceiver which provide full compliance with
MIL-STD-1553/1760 and data bus requirements in a 52-lead Epad 8 x 8 mm QFN with the lowest standby power consumption and
single power supply operation.
The Model ACT4438 performs the front-end analog function of inputting and outputting data through a transformer to a
MIL-STD-1553/1760 data bus with a few external components.
Design of these transceivers reflects particular attention to active filter performance. This results in low bit and word error rate with
superior waveform purity and minimal zero crossover distortion. Efficient transmitter electrical and thermal design provides low
internal power dissipation and heat rise at high as well as low duty cycles.
TRANSMITTER
The Transmitter section accepts bi-phase TTL data at the input and when coupled to the data bus with a 1:2.5 transformer, isolated on
the data bus side with two 55 Ohm fault isolation resistors for direct stub coupling. The data bus signal produced for RISET = 2.7K
Ohm is typically 7.5 Volts nominal P-P at A-A’, See Figure 5. When both DATA and DATA inputs are held low, the transmitter
output becomes a high impedance and is “removed” from the line. In addition, an overriding “INHIBIT" input provides for the
removal of the transmitter output from the line. A logic “1” applied to the “INHIBIT” takes priority over the condition of the data
inputs and disables the transmitter (See Transmitter Logic Waveform, Figure 1).
The transceiver utilizes an active filter to suppress harmonics above 1MHz. The Transmitter may be safely operated at 100% duty
cycle for an indefinite period into a short circuited 1553 bus.
RECEIVER
The Receiver section accepts bi-phase differential data at the input and produces two TTL signals at the output. The outputs are
DATA and DATA, and represent positive and negative excursions of the input beyond a pre-determined threshold (See Receiver
Logic Waveform, Figure 2). The externally set (RTH) thresholds will detect data bus signals exceeding 1.150 Volts P-P and reject
signals less than 0.6 volts P-P when used with a 1:2.5 turns ratio transformer. (See Figure 5 for transformer data and typical
connection).
SCD4438 Rev J
TX DATA IN
TX DATA OUT
DRIVER
TX DATA IN
SHAPING
OUTPUT
STAGE
TX DATA OUT
REFERENCE
COMP.
RX DATA OUT
ACTIVE
FILTER
COMP.
TX INHIBIT
RISET
+5 V
GROUND
RX DATA IN
RX DATA IN
INPUT
AMP
RX DATA OUT
RTH HI
RTH LO
STROBE
BLOCK DIAGRAM (WITHOUT TRANSFORMER)
DATA IN
DATA IN
INHIBIT
LINE TO LINE
OUTPUT
NOTES:
1. DATA and DATA inputs must be complementary waveforms or 50% duty cycle average, with no delays between them.
2. DATA and DATA must be in the same state during off time (both high or low).
FIGURE 1 – TRANSMITTER LOGIC WAVEFORMS
LINE TO LINE
INPUT
DATA OUT
DATA OUT
Note overlap
NOTE: Waveforms shown are for normally low devices.
FIGURE 2 – RECEIVER LOGIC WAVEFORMS
SCD4438 Rev J 12/20/06
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Aeroflex Plainview
ABSOLUTE MAXIMUM RATINGS
Operating Case Temperature
-40°C to +85°C
Storage Case Temperature
-65°C to +150°C
Maximum Die Junction Temperature
+125°C
Positive Power Supply Voltage
-0.3 V to +7.0 V
Receiver Differential Input
±10 V
Receiver Input Voltage (Common Mode)
±5 V
Driver Peak Output Current
650 mA
Total Package Power Dissipation over the full operating case temperature rise at 100% duty cycle
2.2 Watt
ØJC
1°C/W
ØJA
33°C/W
Maximum Junction Temperature Rise over Case (Junction to Case)
2.2°C
Maximum Junction Temperature Rise over Ambient (Junction to Ambient)
72.6°C
ELECTRICAL CHARACTERISTICS – DRIVER SECTION
INPUT CHARACTERISTICS, TX DATA IN OR TX DATA IN
Parameter
Condition
Symbol
Min
Typ
Max
Unit
"0" Input Current
VIN = 0.4V
IILD
-
-0.2
-0.4
mA
"1" Input Current
VIN = 2.7V
IIHD
-
1
40
µA
"0" Input Voltage
VILD
-
-
0.7
V
"1" Input Voltage
VIHD
2.0
-
-
V
INHIBIT CHARACTERISTICS
"0" Input Current
VIN = 0.4V
IILI
-
-0.2
-0.4
mA
"1" Input Current
VIN = 2.7V
IIHI
-
1.0
40
µA
"0" Input Voltage
VILI
-
-
0.7
V
"1" Input Voltage
VIHI
2
-
-
V
Delay from TX inhibit, (0➝1) to inhibited output
tDXOFF
-
150
300
nS
Delay from TX inhibit, (1➝0) to active output
tDXON
-
150
300
nS
Differential Output Noise, inhibit mode
VNOI
-
2
10
mV p-p
Note 1
ZOI
2K
-
-
Ω
ZO = 78Ω
VO
6.5
7.5
9.0
V p-p
tr
100
200
300
nS
VOS
-
-
±90
mV peak
tDTX
-
100
300
nS
Differential Output Impedance (inhibited)
OUTPUT CHARACTERISTICS
Differential output level at point A-A’ on
Figure 5
Rise and Fall Times at point A-A’ on Figure 5
(10% to 90% of p-p output)
Output Offset at point A-A’ on Figure 5, 2.5 µS
after midpoint crossing of the parity bit of the
last word of a 660 µS message
ZO = 78Ω
Delay from 50% point of TX DATA or TX
DATA input to zero crossing of differential
signal
Note 1. Power ON/OFF, measured from 75KHz to 1MHz at Point A-A. See Figure 5.
SCD4438 Rev J 12/20/06
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Aeroflex Plainview
ELECTRICAL CHARACTERISTICS – RECEIVER SECTION
Parameter
Condition
Differential Voltage Range
Common Mode Rejection Ratio
Symbol
Min
Typ
Max
Unit
VIDR
-
-
20
V peak
CMRR
45
-
-
dB
STROBE CHARACTERISTICS (LOGIC "0" INHIBITS OUTPUT)
If not used, a 1K pullup to 5V is recommended
"0" Input Current
VS = 0.4V
IIL
-
-0.2
-0.4
mA
"1" Input Current
VS = 2.7V
IIH
-
1
+40
µA
"0" Input Voltage
VIL
-
-
0.7
V
"1" Input Voltage
VIH
2.0
-
-
V
Strobe Delay (turn-on)
tSD(ON)
-
90
200
nS
Strobe Delay (turn-off)
tSD(OFF)
-
90
200
nS
0.60
0.8
1.15
V p-p
THRESHOLD CHARACTERISTICS (SINEWAVE INPUT )
Input Threshold Voltage (Referred to the bus)
100KHz1MHz
VTH
OUTPUT CHARACTERISTICS, RX DATA AND RX DATA
"1" State
IOH = -0.4mA
VOH
2.5
3.7
-
V
"0" State
IOL = 4mA
VOL
-
0.3
0.5
V
tDRX
-
330
450
nS
Delay, (average)from differential input zero
crossings to RX DATA and RX DATA output
50% points
MAXIMUM CURRENTS, (+5V)
POWER DATA
For RISET = 2.7KΩ
Duty Cycle
Typ
Max
Transmitter Standby
20 mA
30 mA
25% duty cycle
155 mA
185 mA
50% duty cycle
264 mA
335 mA
100% duty cycle
600 mA
650 mA
POWER SUPPLY VOLTAGE
+V
4.75 to 5.5 Volts
Note 2. +V = 5 Volts ±0.1 V, for all measurements unless otherwise specified.
Note 3. Specifications apply over the case temperature range of -40°C to +85°C unless otherwise specfied.
Note 4. All typical values are measured at +25°C.
SCD4438 Rev J 12/20/06
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Aeroflex Plainview
LAST BIT
tf *
90%
Magnified View
OUTPUT OFFSET*
6.5V P-P MIN
9.0V P-P MAX
0 Volts
0 Volts
OUTPUT OFFSET*
10%
2.5 µsec
tr *
*Offset measured at point A-A’ in Fig 5
* Rise and fall times measured at point A-A’ in Fig 5
FIGURE 3 – TRANSMITTER (TX) OUTPUT
WAVEFORM
FIGURE 4 – TRANSMITTER (TX) OUTPUT
OFFSET
2200
+5V
0.1µF
ZO
4, 9,10,30,31,45
TX DATA OUT
1
2
ACT4438
1
7.5KΩ
2
RX DATA IN
RX DATA IN
RISET
34
ZO
1800
1600
A
4
5
6
RTH HI
TX DATA OUT
RTH LO
2000
55Ω
1:2.5
16-19
ZO
POWER DISSIPATION
MILLIWATTS
6.8µF
21-24
3
7
8
48
A’
55Ω
Transformer Model:
Use Pulse/Technitrol
Part# 1553-45 or equivalent
47
GND
1400
1200
Maximum
1000
800
Typical
600
400
200
8, 32, 36, 46, 51
0
2.7KΩ
Resistors 7.5KΩ/ 2.7KΩ ±1%, 1/8 W
10
20
30
40
50
60
70
80
90 100
DUTY CYCLE – PERCENT
Note: Vcc = 5 Volts, Vbus (pt A-A') at 7.5 Volts P-P, ZO = 78Ω
FIGURE 6 – POWER DISSIPATION VS.
DUTY CYCLE
FIGURE 5 – TYPICAL TRANSFORMER
CONNECTION DIRECT STUB
SCD4438 Rev J 12/20/06
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Aeroflex Plainview
PACKAGE PIN OUT DESCRIPTION - ACT4438
Pin #
Function
Pin #
Function
Pin #
Function
Pin #
Function
Pin #
Function
TX DATA OUT
34
RISET
45
VCC
35
NC
46
GND
1
RTH HI
12
NC
23
2
RTH LO
13
NC
24
*
TX DATA OUT *
3
NC
14
NC
25
NC
36
GND
47
RX DATA IN
4
VCC
15
NC
26
NC
37
RX DATA OUT
48
RX DATA IN
5
TX DATA IN
16
TX DATA OUT
27
NC
38
RX STROBE
49
NC
6
TX DATA IN
17
28
NC
39
RX DATA OUT
50
NC
7
TX INHIBIT IN
18
29
NC
40
NC
51
GND
8
GND
19
*
TX DATA OUT *
TX DATA OUT *
TX DATA OUT *
30
VCC
41
NC
52
NC
9
VCC
20
NC
31
42
NC
10
*
VCC *
*
VCC *
21
TX DATA OUT
32
GND
43
NC
11
NC
22
*
TX DATA OUT *
33
NC
44
NC
* High current lines
PACKAGE DESCRIPTION
PIN 1 IDENTIFER & ESD INDICATOR
4438
Integral
Heat Sink
TOP PAD LEAD FRAME VIEW
SCD4438 Rev J 12/20/06
NOTE
1. Dimensions in millimeters
6
Aeroflex Plainview
CONFIGURATIONS AND ORDERING INFORMATION
Model No.
Screening Level
Receiver and Transmitter Data Levels
(See Figure 1)
Case
ACT4438-3
Industrial Temperature
-40°C to +85°C
Normally Low
Epad, 52 lead, 8 x
8 mm, QFN
THE FOLLOWING ARE SOME GUIDELINES FOR THE BOARD LAYOUT OF THE ACT4438
The ACT4438 is a fairly high current device with power supply input currents about 600ma and transmitter output currents in the 500ma
region. Therefore, referring to Figure 5 of the data sheet;
1. The 5V power input lands, pins 9, 10, 30 and 31, should be as wide as possible if they are significantly far away from the power source. If
you have to via up from below use multiple vias to minimize via interconnect resistance. The land resistance should be made as small as
possible so that there will not be a signifcant voltage drop.
2. The transmitter output, pins 16-19 and 21-24 that go to the transformer primary, should run directly to the transformer, do not use vias to
connect. They also should be symmetrical and be as wide as possible to minimize trace resistance. The center-tap of the primary
transformer will also carry the transmitter output currents and should run directly to a ground plane using multiple vias to minimize the via
interconnect resistance.
3. The transmitter output voltage level is set by the 2.7K resistor connected to pin 34. This is a very sensitive node. Therefore keep this node
as short as possible and do not allow any other signal trace to cross under it.
4. In general keep output lines away from input lines such as the receiver output lines pins 47 and 48, which have high level (0V to 4V) fast
switching edges.
5. The Receiver threshold level set by the 7.5K resistor connected to pins 1 and 2 are also sensitive nodes and should also be kept as short as
possible without allowing any other signal trace to cross under them.
6. This package has a heatsink on the bottom side which is on the same plane as the package pins. This heatsink should also be soldered
reflowed to a pad, the same size as the heatsink, which contains multiple vias connecting the heatsink pad to a ground plane layer. This
will remove heat from the die and fan it out across the ground plane.
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CENTRAL
Tel: 719-594-8017
Fax: 719-594-8468
www.aeroflex.com
info-ams@aeroflex.com
Aeroflex Microelectronic Solutions reserves the right to
change at any time without notice the specifications, design,
function, or form of its products described herein. All
parameters must be validated for each customer's application
by engineering. No liability is assumed as a result of use of
this product. No patent licenses are implied.
Our passion for performance is defined by three
attributes represented by these three icons:
solution-minded, performance-driven and customer-focused
SCD4438 Rev J 12/20/06
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