api technologies corp. 3408T Series Manual

INSTALLATION & OPERATING
INSTRUCTIONS
Model 3406T & 3408T Series
SmartStep Programmable Attenuators
IM-425
This documentation may not be reproduced in any form, for any
purpose unless authorized in writing by API / Weinschel, Inc.
© API /Weinschel, Inc.
Frederick, Maryland
2006
REV. 08/16
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GENERAL
This manual provides general installation instruc-
tions and wiring data to be used as anaid in
installing a API / Weinschel 3406T or 3408T
Series SmartStep Programmable Attenuator into
any system or application. Also included are spec-
ifications and other technical data to help in the
installation andoperation of your 3400T Series
Smartstep Programmable Attenuator.
This Series of SmartStep Programmable Step Attenuators is designed for use
inautomatic test equipment and OEM systems operating in the dc to 6 GHz
frequency range. Each cell contains a standard TO-5 type double-pole, double-
throw relay that provides a minimum loss or attenuated path for the RF signal
which is controlled by a built-in digital interface shown in Figure 1.
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Figure 1. SmartStep Driver Circuitry
Non-Volatile
Configuration
Memory
Single-Chip
Microcontroller
Relay
Drivers
TTL/CMOS
Compatible
Digital Interface
+12 to
+15 V
Input
To
Attenuator
Relays
EMI
Filters
+5 V
Regulator
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3400T Series SmartStep Programmable Attenuators
BUILT-IN SMARTSTEP DRIVER CIRCUITRY: These SmartStep attenuators feature an
internal microcontroller-based driver that provides a TTL-level digital interface for control of
the attenuator relays. This card simplifies operation and interfacing requirements, while at
the same time providing for greatly enhanced flexibility over past designs. User-selectable
modes of operation include both parallel and serial Smartstep bus. The parallel mode pro-
vides a simple, one-bit per relay on/off control with internal pullups for use primarily in
single attenuator applications. This mode allows the attenuator to be controlled via a vari-
ety of methods, such as a TTL-level digital output port, or mechanical toggle switches. The
Smartstep mode provides a two-wire serial bus structure and protocol for connecting a
number of devices to a single host control interface, suitable for use in larger system and
sub-system applications.
The SmartStep contains non-volatile configuration memory that is used to hold a wide vari-
ety of attenuator and driver-dependant parameters, including serial number, attenuator cell
dB values, relay configurations, and switching requirements, which are all accessable via
the Smartstep interface. This frees the system designer from such low-level details, allow-
ing faster integration. In either operational mode, the microcontroller enters an idle
condition during periods of inactivity, turning off all on-board clocks, reducing EMI con-
cerns, and lowering power consumption. On-board regulation for the digital circuitry allows
the SmartStep to operate from a single input supply voltage.
CELL CONFIGURATION
The table below list all the standard attenuation ranges and cell configurations for
API / Weinschel 3400T Series Smartstep Programmable Attenuators (Models
3406T & 3408T). Note the dash number is the attenuation value of your attenu-
ator.
Cell Range/
Model No. No. Step Size
(dB) D7 D6 D5 D4 D3 D2 D1 D0
3406T-55 6 55/1 24 16 8 4 2 1
3408T-55.75 8 55.75/0.25 24 16 8 4 2 1 0.5 0.25
3408T-103 8 103/1 24* 16 8 4 2 1 24 24*
* Combined Cells
Data Bit-Cell Value (dB)
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INSTALLATION
MOUNTING: Each Programmable Step Attenuator is supplied with two mount-
ingholes (4-40 UNC-2B x 0.24 MIN DP) located on the bottom side of the
attenuator.
RF CABLE INSTALLATION: Care should be taken to prevent strain on the inter-
connecting cables, since damage here may not always be apparent. Check the
attaching RF cables and the SMA connectors for signs of cracked insulation
and/or bent or worn pins prior to connection. Tests show that connectors must be
clean for accuracy and stability. This requires an inspection and cleaning of each
connector immediately before use. When cleaning precautions are observed reg-
ularly, connectors can maintain their stability for over several thousand
connection cycles. Weinschel recommends a torque value of 7 to 10 inch pounds
when connecting any RF cable to the attenuator's RF connectors.
DEVICE INTERFACE BUS (DIB) CONNECTOR WIRING: Figure 2 shows the
connectors contact pin numbering scheme and the signal designator for signal
present at each contact pin.
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PIN 1
PIN 2
PIN 14
PIN 13
Name Pin Description
VIN 1 dc Supply Voltage, +12 to 15 V (1)
VIN 2 dc Supply Voltage, +12 to 15 V (1)
GND 3,4 dc Return
D0/SDA 7 Data Bit 0 (isb)/I2C SDA
D1/SCL 8 Data Bit 1//I2C SCL
D2 5 Data Bit 2
D3 6 Data Bit 3
D4 11 Data Bit 4
D5 12 Data Bit 5
D6 9 Data Bit 6
D7 10 Data Bit 7 (msb)
Mode 13 Parallel/Serial Mode Select
Select 1=Parallel
0=Serial
This pin has a 22K resistive pull-up to 5 V.
Leave unconnected for parallel mode operation.
/RST 14 Reset Input, low active
This pin has a 22K resistive pull-up to 5 V
Leave unconnected if not used.
Note: D0-D7 pins contain weak active pullups, capable of sourcing
approximately 150 mA.
(1) Voltage may be applied to either PIN 1 or 2 or both.
Figure 2. DIB Connector Wiring
NOTE: Pin locations same
with or without cover.
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PARALLEL MODE OPERATION:
In the parallel mode of operation, the Smartstep attenuator accepts TTL-level
parallel data on the D0-D7 input data lines. Each data line controls a separate
attenuation cell, where a logic 1 input (TTL high) engages the attenuation cell, and
a logic 0 input (TTL low) bypasses the cell, providing a through path. The data
lines have a weak active pull-up to +5V, and therefore if the pin is left unconnect-
ed (or floating), will engage the attenuation cell. The on-board microcontroller
debounces the data lines and generates the proper timing and control sequence
for operation of the relays. The data line inputs are not latched, and must be driv-
en with a constant level to keep the desired attenuation setting.
SERIAL MODE OPERATION:
In the serial mode of operation, the Smartstep attenuator communicates over a
two-wire serial bus to the Weinschel Model 8210 Smartstep Interface. The bus
uses a clock (SCL) and data (SDA) line to send and receive programming and
configuration information. The messages sent over the bus use the software
protocol as defined in the ACCESS.bus™ V2.2 specification (Base Protocol) with
Weinschel-specific extensions to support the control of step attenuators (StepAttn
Protocol). These protocols and operating instructions can be located in the Model
8210 instruction manual (IM-288). The ACCESS.bus™ messages have the
following format:
Byte# D7 D6 D5 D4 D3 D2 D1 D0 Description
1 D7 D6 D5 D4 D3 D2 D1 0 Destination address
2 S7 S6 S5 S4 S3 S2 S1 0 Source address
3 P L6 L5 L4 L3 L2 L1 L0 Protocol flag & Msg Length
4msg body- 0 to 127 bytes
Length+4 X7 X6 X5 X4 X3 X2 X1 X0 Checksum
For an indepth discussion of the hardware and software operation, refer to the
ACCESS.bus™ specification.
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3400T Series SmartStep™ Programmable Attenuators
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SPECIFICATIONS
NOMINAL IMPEDANCE: 50 Ω
FREQUENCY RANGE: dc to 6.0 GHz
DRIVER INTERFACE:
Input Supply Voltage: +12.0 to +15.0V
Control Signals: TTL/CMOS compatible
Interface Modes: parallel/ I2C serial
DC Characteristics (at 25 °C):
Digital Interface:
DRIVER INTERFACE:
Parameter Specification
VIL Low-level input V: -0.5V min, 0.8V max
VIH High-level input V: 2.0V min, 5.25V max
IPU Pullup current: 50 μA min, 400 μA max
VIN Supply Voltage: +12.0 to +15.0V
IIN Supply current: 25 mA (digital section)
ICELL Supply current: 16.6 mA @ 12V
POWER RATING: 1 watt average to 25°C ambient temperature, derated linearly to
0.25 watt @ 71°C. 50 watts peak (5 μsec pulse width; 1% duty cycle)
POWER COEFFICIENT: < 0.005 dB/dB/watt
RATED SWITCH LIFE: 5 million cycles operations per cell @ 0 dBm
CYCLING RATE: 5 Hz maximum per relay
TEMPERATURE: -30° to +70°C
CONNECTORS: SMA female connectors per MIL-STD-348 interface dimensions - mate
nondestructively with MIL-C-39012 connectors.
INTERFACE CONNECTOR: 14 pin .025 square post header on .1 center. Mates with Amp
connector 746285-2 or equivalent.
CONSTRUCTION:
Housing: Aluminum
Connectors: Stainless steel body and beryllium
copper contacts.
Control terminals: Brass/Copper, Silver plated
WEIGHT (Typical): 3406T-X: 99 g (3.5 oz)
3408T-X: 135 g (4.8 oz)
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3400T Series SmartStep™ Programmable Attenuators
Model NO. Attenuation Cell
Number Cells Range/Steps Increments
(dB) (dB)
3406T-55 6 55/1 1, 2, 4, 8, 16, 24
3408T-55.75 8 55.75/0.25 0.25, 0.5, 1, 2, 4, 8, 16, 24
3408T-103 8 103/1 1, 2, 4, 8, 16, 24, 48*
*48 dB cell comprised of two 24 dB cells
CELL CONFIGURATIONS:
INCREMENTAL ATTENUATION ACCURACY:
Frequency Accuracy
Range (GHz)
dc - 3 +0.3 dB or 2% whichever is greater
3 - 6 +0.4 dB or 3% whichever is greater
MAXIMUM INSERTION LOSS (dB):
Frequency 3206-55 3408-55.75
Range (GHz) 3408-103
dc - 3 2.60 3.40
3 - 6 3.80 5.00
MAXIMUM SWR:
Frequency Range (GHz) SWR
dc - 3 1.30
3 - 6 1.45
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PHYSICAL DIMENSIONS:
“A”
“B”
“C”
“D”
49.9
(1.93)
NOTE: All dimensions are given in mm (inches) and are nominal, unless otherwise specified.
Model No. No. Cells A B C D
3408T-X 8 136.1 (5.36) 123.4 (4.86) 7 EQ SPCS @ 15.20 (.60) = 106.7 (4.20) 128.5 (5.06)
3406T-X 6 105.7 (3.66) 93.0 (3.66) 5 EQ SPCS @ 15.20 (.60) =76.0 (3.00) 98.0 (3.86)
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9
3400T Series SmartStep™ Programmable Attenuators
ACCESSORIES
Model 8210 Smartstep Interface: The Model 8210 Smartstep Interface provides a flexi-
ble, low cost solution for the operation of programmable step attenuators and other
electromechanical devices under computer control. Designed to interface to Weinschel's
new line of Smartstep Programmable Attenuators, the 8210 represents a new concept in
device control applications for bench test and subsystem designs. The 8210 provides a
high-level interface from various industry standard communications interfaces, including
IEEE-488/RS232/RS422/RS485, to the Smartstep's serial Device Interface Bus. Typical
Setup shown below:
CONTACTING API / Weinschel
In the event you're having difficulty or believe that the components are defective,
please contact API / Weinschel immediately. An apparent malfunction may be
corrected over the phone by contacting the Customer Service Department at
API / Weinschel. DO NOT send the product back to the factory without prior
authorization (RMA number). When it is necessary to return an item, state the
symptoms or problems, catalog and type number of the attenuator, and date of
original purchase. Also write the company name, your name, and phone number
on an index card. Then attach the card to the attenuator to be returned.
For more information or any questions about your Programmable Step
Attenuators and/or other API / Weinschel products, contact the Sales
Department at API / Weinschel.
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API / Weinschel Warranty
PRODUCTS: API / Weinschel warrants each product it manufactures to be free
from defects in material and workmanship under normal use and service any-
where in the world. API / Weinschel's only obligation under this Warranty is to
repair or replace, at its plant, any product or part thereof that is returned with
transportation charges prepaid to API / Weinschel by the original purchaser
within ONE YEAR from the date of shipment.
The foregoing Warranty does not apply to, and in API / Weinschel's sole opin-ion,
products that have been subject to improper or inadequate maintenance,
unauthorized modifications, misuse, or operation outside the environmental spec-
ifications for the product.
SOFTWARE PRODUCTS: API / Weinschel software products are supplied
without representation or Warranty of any kind. API / Weinschel, therefore,
assumes no responsibility and will not accept liability (consequential or otherwise)
arising from the use of program materials, disk, or tape.
The Warranty period is controlled by the Warranty document furnished with each
product and begins on the date of shipment. All Warranty returns must be author-
ized by API / Weinschel prior to their return.
API / Weinschel's Quality System Certified to:
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