Mini-Circuits RUDAT Series User manual

AN-49-005 © 2022 Mini-Circuits
Rev. M | ECO-015752 | 10-Nov-2022 Page 1
User Guide
Programmable Attenuators

AN-49-005 © 2022 Mini-Circuits
Rev. M | ECO-015752 | 10-Nov-2022 Page 2
Table of Contents
1 - General Information .....................................................................................................4
1.1. User-Guide Scope.................................................................................................................................................................... 4
1.2. Support Contacts..................................................................................................................................................................... 4
1.3. Warranty & RMA Returns ....................................................................................................................................................... 4
1.4. End of Life................................................................................................................................................................................ 4
1.5. Definitions ............................................................................................................................................................................... 4
2 - About Mini-Circuits Programmable Attenuators...........................................................5
2.1. Introduction ............................................................................................................................................................................ 5
2.2. Intended Applications ............................................................................................................................................................. 5
2.3. Model Selection Guide ............................................................................................................................................................ 6
2.4. Environmental Specifications.................................................................................................................................................. 6
2.5. Supported Software Environments......................................................................................................................................... 7
2.6. Conformity .............................................................................................................................................................................. 7
2.7. Accessories and Options ......................................................................................................................................................... 8
2.8. Service and Calibration............................................................................................................................................................ 8
2.9. Safety & Precautions ............................................................................................................................................................... 8
2.10. Functional Block Diagram...................................................................................................................................................... 9
3 - Software Setup ...........................................................................................................11
3.1. System Requirements ........................................................................................................................................................... 11
3.2. Software Downloads & Resources ........................................................................................................................................ 11
3.3. Software Installation ............................................................................................................................................................. 11
4 - Hardware Setup..........................................................................................................13
4.1. USB Control (All models) ....................................................................................................................................................... 13
4.2. Ethernet Control (RCDAT models)......................................................................................................................................... 13
4.3. Daisy-Chain Control............................................................................................................................................................... 14
4.3.1. Setup Instructions ......................................................................................................................................................... 15
4.4. RS232 Control (with power via USB) ..................................................................................................................................... 15
4.4.1. Setup Instructions ......................................................................................................................................................... 15
4.5. RS232 Control (with power via D-Sub).................................................................................................................................. 16
4.5.1. Setup Instructions ......................................................................................................................................................... 16
4.6. SPI Control (RUDAT-13G-xx models) ..................................................................................................................................... 17
4.6.1. SPI Communication ....................................................................................................................................................... 17
4.6.2. Setup Instructions ......................................................................................................................................................... 18
4.7. TTL Control (RCDAT-18G-xx models)..................................................................................................................................... 19
4.7.1. TTL Communication....................................................................................................................................................... 19
4.7.2. Setup Instructions ......................................................................................................................................................... 20
4.8. Trigger In (RCDAT-18G-xx models) ........................................................................................................................................ 21

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Table of Contents (continued)
5 - Using Mini-Circuits’ GUI .............................................................................................. 22
5.1. Getting Started...................................................................................................................................................................... 22
5.1.1. USB Control ................................................................................................................................................................... 23
5.1.2. RS232 Control................................................................................................................................................................ 23
5.1.3. Ethernet Control............................................................................................................................................................ 23
5.2. Operating the Attenuator ..................................................................................................................................................... 25
5.2.1. Manual Mode Functions................................................................................................................................................ 25
5.2.2. Automatic Mode Functions ........................................................................................................................................... 26
5.2.3. Log Attenuation Changes .............................................................................................................................................. 27
5.2.4. Configuration Settings ................................................................................................................................................... 28
5.3. Ethernet Configuration (RCDAT-models) .............................................................................................................................. 29
5.3.1. Default IP Configuration ................................................................................................................................................ 29
5.3.2. Default Static / “Link-Local” IP Address......................................................................................................................... 29
5.3.3. Recovery of IP Configuration via USB............................................................................................................................ 29
5.3.4. Default Factory Setting.................................................................................................................................................. 29
5.3.5. Ethernet Setting Screen................................................................................................................................................. 30
5.3.6. Ethernet Setting Descriptions........................................................................................................................................ 30
5.3.7. Ethernet Configuration Tool.......................................................................................................................................... 32
5.4. Sweep and Hop Functions..................................................................................................................................................... 33
5.4.1. PC Control Mode ........................................................................................................................................................... 33
5.4.2. High-speed Mode .......................................................................................................................................................... 33
5.4.3. Attenuator Switching Time............................................................................................................................................ 34
5.5. Daisy-Chain Control with Dynamic Addressing ..................................................................................................................... 35
5.5.1. Master/Slave Connection with USB Control.................................................................................................................. 35
5.5.2. Dynamic Addressing Functions...................................................................................................................................... 36
5.5.3. Configuring Units with Dynamic Addressing ................................................................................................................. 37
5.6. Multiple Attenuation Modes (RCDAT-40G-30) ..................................................................................................................... 37
5.7. Pop-up Alerts......................................................................................................................................................................... 38
5.8. Firmware Update .................................................................................................................................................................. 39
5.8.1. Requirements ................................................................................................................................................................ 39
5.8.2. Process .......................................................................................................................................................................... 39
5.9. Firmware Recovery ............................................................................................................................................................... 42
5.9.1. Recovery Steps (except RCDAT-xG-120H & RCDAT-18G-xx models)............................................................................. 42
5.9.2. Recovery Steps (RCDAT-xG-120H & RCDAT-18G-xx models) ........................................................................................ 43
6 - Revision History..........................................................................................................44
7 - Contact .......................................................................................................................46

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1 -General Information
1.1. User-Guide Scope
This user guide provides general introduction, installation instructions and operating information for Mini-Circuits’ programmable
attenuators: RUDAT and ZVVA series (USB & RS232), and RCDAT series (USB & Ethernet).
For information on Mini-Circuits’ programmable attenuators see: https://www.minicircuits.com/app/AN49-011.pdf
1.2. Support Contacts
We are here to support you every step of the way. For technical support and assistance, please contact us at the email address
below or refer to our website for your local support:
•[e-mail]
•https://www.minicircuits.com/contact/worldwide_tech_support.html
1.3. Warranty & RMA Returns
Mini-Circuits provides a limited time warranty with all products. Please contact your account manager or refer to our website for
full details: https://www.minicircuits.com/support/ordering.html
If you have any questions or concerns with your product, please contact us in the first instance through
[e-mail]. Our team will work with you promptly to understand and resolve any issues. As a software-
controlled instrument, it is usually possible to resolve issues remotely without requiring the unit to be returned to the factory.
In the event that a return to the factory is necessary, Mini-Circuits will provide an RMA number and full return instructions.
1.4. End of Life
Please contact [e-mail] to review environmentally friendly end of life disposal options.
1.5. Definitions
Note:
•A note advises on important information you may need to ensure proper operation of the equipment.
•There is no risk to either the equipment or the user.
Caution:
•A caution advises about a condition or procedure which can cause damage to the equipment.
•There is no danger to the user.
Warning:
•A warning alerts to a possible risk to the user and steps to avoid it.
•Do NOT proceed until you are sure you understand the warning.

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2 -About Mini-Circuits Programmable Attenuators
2.1. Introduction
Mini-Circuits has developed a series of programmable attenuators with powerful software support and a range of control options
to suit any application:
•USB - All models support the USB Human Interface Device (HID) class for plug & play operation.
•Ethernet - RCDAT models support HTTP & Telnet communication over an IP network, with SSH available on some models for
secure communication.
•RS232 - RUDAT & ZVVA models include a D-Sub interface for compatibility with RS232 control systems.
•SPI - RUDAT-13G models include additional support for 3-wire SPI communication.
•TTL - RCDAT-18G-63 includes a TTL control interface for high-speed parallel control.
•Daisy-chain control - Some models include Mini-Circuits' unique dynamic daisy-chain feature, allowing multiple units to be
connected together and controlled via a single USB or Ethernet connection.
Refer to section 2.4 for details of specific models.
The programmable attenuators come in different variations with:
•Wide frequency ranges, from 9 kHz and up to 67 GHz
•Fine attenuation resolutions, as low as 0.05 dB
•Wide attenuation ranges, up to 120 dB
The attenuators are light, compact and can be powered from the USB bus or external power supply, increasing system flexibility.
These models are “plug & play” devices which require no drivers for any of the supported interfaces. The attenuators can be
controlled via the supplied GUI software or with most common lab test software the user can set remotely any attenuation level
in range almost instantly. Using the RCDAT’s models Ethernet control it is possible to control the models from almost any
computer, or even a smartphone, with a network connection from anywhere in the world.
For additional details, performance data and graphs, outline drawing, ordering information and environmental specifications,
see our catalog at: https://www.minicircuits.com/WebStore/RF-Programmable-Step-Attenuators.html
2.2. Intended Applications
Mini-Circuits programmable attenuators are intended for indoor use in:
•Lab and test equipment setups for both manual and automated measurements.
•Control systems.
•Production test equipment.
The attenuators can be used by anyone familiar with the basics of electronics measurements or electronic control systems.

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2.3. Model Selection Guide
Model name Frequency range
Atten.
range
(dB)
Attenuation
resolution (dB)
Max input
power (dBm) Control protocols
RCDAT-3000-63W2
50 MHz – 3 GHz
63
1
+33
USB, HTTP, Telnet
RCDAT-4000-120
1 MHz – 4 GHz
120
0.25
+20
USB, HTTP, Telnet
RCDAT-6000-30
1 MHz – 6 GHz
30
0.25
+20
USB, HTTP, Telnet
RCDAT-6000-60
1 MHz – 6 GHz
60
0.25
+20
USB, HTTP, Telnet
RCDAT-6000-90
1 MHz – 6 GHz
90
0.25
+20
USB, HTTP, Telnet
RCDAT-6000-110
1 MHz – 6 GHz
110
0.25
+20
USB, HTTP, Telnet
RCDAT-6G-120H
200 MHz – 6 GHz
120
0.05
+23
USB, HTTP, Telnet, SSH
RCDAT-8G-120H
200 MHz – 8 GHz
120
0.05
+23
USB, HTTP, Telnet, SSH
RCDAT-8000-30
1 MHz – 8 GHz
30
0.25
+28
USB, HTTP, Telnet
RCDAT-8000-60
1 MHz – 8 GHz
60
0.25
+28
USB, HTTP, Telnet
RCDAT-8000-90
1 MHz – 8 GHz
90
0.25
+28
USB, HTTP, Telnet
RCDAT-18G-63
100 MHz – 18 GHz
63
0.25
+24
USB, HTTP, Telnet, RS232, TTL
RCDAT-30G-30 100 MHz – 30 GHz 30 0.5 +24
USB, HTTP, Telnet, Daisy-
chain
RCDAT-40G-30 100 MHz – 40 GHz 30 0.5 +24
USB, HTTP, Telnet, Daisy-
chain
RCDAT-50G-30 100 MHz – 50 GHz 30 0.5 +24
USB, HTTP, Telnet, Daisy-
chain
RUDAT-4000-120
1 MHz – 4 GHz
120
0.25
+20
USB, RS232
RUDAT-6000-30
1 MHz – 6 GHz
30
0.25
+20
USB, RS232
RUDAT-6000-60
1 MHz – 6 GHz
60
0.25
+20
USB, RS232
RUDAT-6000-90
1 MHz – 6 GHz
90
0.25
+20
USB, RS232
RUDAT-6000-110
1 MHz – 6 GHz
110
0.25
+20
USB, RS232
RUDAT-13G-60
10 MHz – 13 GHz
60
0.5
+23
USB, RS232, SPI
RUDAT-13G-90
10 MHz – 13 GHz
90
0.5
+23
USB, RS232, SPI
UDAT-67G-30
9 kHz – 67 GHz
31.5
0.5
+26
USB, Daisy-chain
UDAT-67G-60
9 kHz – 67 GHz
63
0.5
+26
USB, Daisy-chain
ZVVA-3000*
20 MHz – 3 GHz
25
0.1
+23
USB, RS232
* This model is not recommended for new designs. Available while supplies last.
For detailed model performance, data and graphs, outline drawing, ordering information and environmental specifications click
on the model part number.
For setup and control instructions for the different control protocols see chapter 4.
2.4. Environmental Specifications
Mini-Circuits’ programmable attenuators are intended for operation in office, laboratory, or production test environments. Do
not use in any condition which exceeds the published environmental specifications.
Condition
Specification
Operating temperature
0°C to +50°C
Humidity
5% to 85% RH (non-condensing)
Altitude
Up to 2000 m (6560 ft)
Pollution degree
2 - Normally only non-conductive pollution occurs (per IEC 61010)

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2.5. Supported Software Environments
Mini-Circuits programmable attenuators have been tested in the following operating systems:
•32-bit systems: Windows 7 or later.
•64-bit systems: Windows 7 or later (GUI & API); Linux.
The attenuators will work with almost any software environment that supports ActiveX or .Net, including Python, C#, LabVIEW,
MatLab and more. Please contact us for support.
Refer to the programming manual for more information on attenuator programming.
2.6. Conformity
Mini-Circuits’ programmable attenuators conform to the following international standards:
Standard
Meaning
CE
Meets the requirements of the following applicable European directives and carries the CE marking accordingly:
•Low Voltage – Directive 2014/35
•Electromagnetic Compatibility – Directive 2014/30/EU
•Restriction of the Use of certain Hazardous Substances in Electrical and Electronic Equipment (RoHS) –
Directive 2015/863
UKCA
Meets the requirements of the following applicable UK directives and carries the UKCA marking accordingly:
•Electrical Equipment (Safety) Regulations 2016
•Electromagnetic Compatibility Regulations 2016
•
The Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment
Regulations 2012
FCC
This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part
15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in
a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not
installed and used in accordance with the instructions, may cause harmful interference to radio communications.
However, there is no guarantee that interference will not occur in a particular installation.
USB 2.0
The model meets the specifications of the Universal Serial Bus version 2.0 communication standard as described
by USB-IF.
USB HID The model meets the requirements for Universal Serial Bus Human Interface Devices according to USB-IF’s
Device Class Definition for Human Interface Devices firmware revision 1.11.
RS232 The RUDAT series meets all requirements for RS232 standard.
TCP/IP The RCDAT series models’ Ethernet communication complies with the specifications of the Transmission Control
Protocol (TCP) and Internet Protocol (IP) as defined in RFC 791 and RFC 793.
HTTP The
RCDAT
series supports all requirements for communicating with the Hypertext Transfer Protocol (HTTP) as
defined in RFC 1945.
Telnet The RCDAT series supports all requirements for communicating with the Telnet protocol, as defined in RFC 854.
SSH The RCDAT models which specify SSH control, support the requirements for SSH protocol as defined by RFCs
4250-4253, 4419, 5647, 5656 and 6668.

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2.7. Accessories and Options
The programmable attenuators are supplied with a control cable:
•3.3 ft (1.0 m) USB cable: USB type A (Male) to USB type Mini-B (Male)
•3.3 ft (1.0 m) USB cable: USB type A (Male) to USB type C (Male)
The following optional accessories are available (see models’ datasheet for details):
•Ethernet cable: RJ45 (Male) to RJ45 (Male) Cat 5E cable
•RS232 & TTL cable: 15 pin D-sub (Female) to Pig-tail (bare wires)
•RS232 cable: 9 pin D-sub (Male) to 9 pin D-sub (Female)
•USB extension cable: USB type A (Male) to USB type A (Female)
•Daisy-chain cable: Digital snap fit (Male-Male) cable assembly connectors
•AC/DC power adapter suitable for a wide selection of wall sockets
•Mounting bracket
•The full software package including GUI, API DLL files and programming instructions, can be downloaded from
https://www.minicircuits.com/softwaredownload/patt.html
2.8. Service and Calibration
The programmable attenuators do not require any periodic service or calibration.
The only user-performed service possible for attenuator modules is external cleaning of the case and connectors as needed. Do
not use any detergents or spray cleaning solutions. The case can be cleaned with a soft, slightly dampened cloth and the
connectors with an alcohol solution. Do not allow any liquid ingress into the case or connectors.
2.9. Safety & Precautions
Mini-Circuits’ programmable attenuators contain no user serviceable parts and should not be opened. Discontinue use and
contact Mini-Circuits in the event of visible damage to any parts.
Please observe the following safety precautions at all times when using Mini-Circuits attenuator modules:
Caution:
•Do not input to the device signals of greater power than the attenuator is rated for in its datasheet.
•Safe power input degrades below specified frequency range. Do not input signals below the specified frequency
range.
Warning:
•Properly ground all equipment to reduce the risk of accidental electrical shock.

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2.10. Functional Block Diagram
Figure 2.11a functional block diagrams RUDAT(left) and RCDAT(right)
Figure 2.11b functional block diagram for ZVVA(left) and RCDAT with daisy-chain(right)

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Figure 2.11c functional block diagram for RCDAT-18G-xx(left) and UDAT with daisy-chain(right)

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3 -Software Setup
3.1. System Requirements
The minimum requirements for the installation of the Mini-Circuits programmable attenuator software package and API on the
host PC are:
•Microsoft Windows 7 or later (32- or 64-bit).
•Intel i3 or equivalent (recommended).
When using the supplied power adaptor, a power source of 110-220VAC (with a socket matching one of the two pin plugs provided)
is also needed.
Control method
Required support
RS232 control
Serial COM port
USB control
USB HID
Ethernet control
Network connection
3.2. Software Downloads & Resources
The full programmable attenuator software package (including GUI, API and documentation) is available for download from:
https://www.minicircuits.com/softwaredownload/patt.html
3.3. Software Installation
1. Save all work in progress and close any other programs that may be running.
2. Download the programmable attenuator software from the Mini-Circuits website.
3. Extract the downloaded zip file and begin the installation process and double-click the Setup.exe icon.
4. If Microsoft Defender SmartScreen provides a warning about an unrecognized app, select More Info and then Run Anyway.
5. If prompted by Windows User Account Control, enter user credentials for an account allowing software installation.

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6. Click Next to begin the installation.
7. Click Yes to accept the license agreement.
8. Click Exit on the final window confirming that installation completed successfully.
9. In the event of any issues with installation, please contact [e-mail] for support.

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4 -Hardware Setup
4.1. USB Control (All models)
Connect the attenuator to the computer using the provided USB cable or equivalent one, and then connect the required RF
connections.
Caution:
•The maximum allowed RF input for programmable attenuator models is reduced at low frequencies.
•Exceeding these values may damage the attenuator. Check the individual model datasheet and do not exceed
the specified limits.
4.2. Ethernet Control (RCDAT models)
•Connect unit to power source via USB cable or the provided power adaptor.
•Connect a standard network cable between the unit’s RJ45 socket and the network port.
•Ensure the network indicators on the unit’s RJ45 socket light up after a few seconds.
•Connect the unit’s input and output RF ports to your system.
Note:
•For RCDAT-18G-xx models, the 5V DC supply can also be applied to pin #1 of the D-sub instead of the USB connector.

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4.3. Daisy-Chain Control
Some models include Mini-Circuits’ novel dynamic addressing daisy-chaining interface which allows multiple modules to be
connected together into a master/slave chain, with independent control of each module through the single USB connection of the
master unit (see section 2.4 for models supporting this function).
The serial master/slave bus allows connecting modules of different types to the same daisy-chain as long as they all support Mini-
Circuits’ dynamic addressing setup. To add a new module, simply connect it the daisy-chain and refresh the address listing -- no
need to reset any of the existing modules or assign addresses manually.
Modules will have their addresses assigned automatically when the USB connection from the PC to master is established, or when
a refresh address command is issued. The module connected to the computer USB port will be assigned address 0 (master), and
subsequent modules connected through it will get incrementing addresses, starting from 1 to N. All control will be through the
master module (address 0) which is the only one communicating with the PC.
Note:
•It is possible to connect up to 99 units in a single setup as long as power considerations are taken into account. Refer to model
datasheets for number of units tested in series of a given model.
•It is recommended to disable the Ethernet function (see section 3.3.5) of the slave units before connecting them in series to
reduce power consumption.

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4.3.1. Setup Instructions
Digital & DC connections for daisy-chain control can be done in any order so long as addresses are refreshed once all units and
power supplies are connected.
1. Arrange the required switch modules on the work surface in the order they are to be addressed.
2. Use the serial control cables (CBL-1.5FT-MMD+, CBL-5FT-MMD+, or equivalent) to connect the units together in the daisy-
chain, from Serial CTRL Out of the first unit, to Serial CTRL In of the second, and so forth.
3. Note the DC current draw of each switch in the daisy-chain from the published datasheets.
4. Starting from the first switch in the daisy-chain, sum the DC current draw of each switch to confirm whether the total
exceeds the maximum pass-through current (500 mA), or the maximum available from the USB supply (if lower).
5. If required, connect an additional 5V DC power supply to the USB port of one of the daisy-chained modules, to keep the DC
consumption of the previous group beneath the specified limit.
6. Repeat the check from this module forward and add additional power supplies as necessary.
7. Finally, connect the USB cable from the first switch to the control PC and the complete chain will power up and
automatically assign address (from 00 to nn).
8. To add additional units to the daisy chain just repeat step 6 from the last unit connected to a power supply then connect the
additional units with serial control cables and click on the address refresh button in the GUI (below the list of units
connected).
4.4. RS232 Control (with power via USB)
4.4.1. Setup Instructions
•Connect unit to power source via USB cable or the provided power adaptor.
•Connect a D-Sub cable between the unit’s D-Sub port and computer’s serial port.
•Connect the unit’s input and output RF ports to your system.
5V AC/DC
wall power adaptor
Connect to PC’s
Serial port
MUSB-CBL-3+ or Eqv.
Connect to
User system
D-SUB9-MF-6+
or Eqv.
Connect to
User system
Note:
•See individual model data sheet for specific model pinout.
•For RUDAT-13G-xxx verify pins 7-9 in the D-Sub connector are not connected to any active signal as this may disrupt proper
operation.
•For RCDAT-18G-xx verify pin 5 is not connected to any active signal as this may disrupt proper operation. See section 4.8 for
details on using Trigger.

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4.5. RS232 Control (with power via D-Sub)
This option requires the use of an RS232 port wired to supply +5VDC at Pin #1.
It is supported in the following units:
Model P/N
Serial number
RCDAT-18G-63
All serial numbers
RUDAT-6000-30
11405010010 and greater
RUDAT-6000-60
11407150001 and greater
RUDAT-6000-90
11403230000 and greater
Other RUDAT models
All serial numbers
ZVVA-3000
All serial numbers
4.5.1. Setup Instructions
•Connect unit to power source via USB cable or the provided power adaptor.
•Connect a control cable between the unit's D-sub connector and the controller, wired according to the pin-out table in the
datasheet.
•Connect the unit’s input and output RF ports to your system.

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4.6. SPI Control (RUDAT-13G-xx models)
4.6.1. SPI Communication
SPI control allows the device’s attenuation to be set using a simple serial data sequence of LVTTL logic levels. It is a synchronous
communication method designed for minimal control systems (no need for a PC), and as such, it is not possible to query any of
the attenuator’s parameters in this mode of operation.
SPI uses an 8-bit serial in, parallel-out shift register buffered by a transparent latch with Data, Clock, and Latch Enable (LE) voltages
compatible with LVTTL. The Data and Clock inputs allow data to be serially entered into the shift register, a process that is
independent of the state of the LE input. The Value entered should be desired attenuation x2 -- for example, to set an attenuation
level of 45.5 dB the user will enter 91 decimal which is 0101 1011 in binary.
The LE input controls the latch. When LE is high, the latch is transparent and the contents of the serial shift register control the
switch. When LE is brought LOW, data in the shift register is latched.
The shift register should be loaded while LE is held low to prevent the attenuation state from changing as data is entered. The LE
input should then be toggled high and brought low again, latching the new data. The timing for this operation is defined by the
“SPI Timing” diagram and “SPI Interface AC Characteristics“ table.
Note:
•SPI voltage levels and timing instructions are covered in the models’ datasheets.
•SPI is a synchronous communication method designed for minimal control systems and thus, it is not possible to query any of
the attenuator’s parameters in this mode of operation.
•As SPI and RS232 control share the same plug, when using SPI control it is recommended to keep pins #2 & #3 disconnected
to avoid problems with proper operation.
SPI Interface AC Characteristics
Symbol
Parameter
Min
Max
Units
fclk
Serial data clock frequency 10 MHz
tclkH
Serial clock High time 5 ns
tclkL
Serial clock Low time 5 ns
tLESUP
LE setup time after last clock falling edge 30 ns
tLEPW
LE minimum pulse width 20 ns
tSDSUP
Serial data set-up time before clock rising
edge
5 ns
tSDHLD
Serial data hold time after clock falling edge 5 ns

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Figure 4.6.1: SPI timing diagram
4.6.2. Setup Instructions
•Connect the SPI Clock, Data and Latch Enable pins (see pinout table below) to your I/O control device.
•Connect power as for RS232 control.
•Note the indicator lights up.
•Connect RUDAT input and output SMA ports to your system.
Parameter
Conditions
Min
Typ
Max
Units
Voltage Levels
Logic High (Input)
2.1
-
3.3
V
Voltage Levels
Logic Low (Input)
0
-
0.8
V
Control Current
Per Pin
-
-
1
mA
Clock Frequency
-
-
-
10
MHz
Pin #
Function
1
+5 VDC
2
RS232
Transmit
3
RS232 Receive
4
Not
Connected
5
GND
6
Factory Use
7
SPI LE
8
SPI Clock
9
SPI Data

AN-49-005 © 2022 Mini-Circuits
Rev. M | ECO-015752 | 10-Nov-2022 Page 19
4.7. TTL Control (RCDAT-18G-xx models)
4.7.1. TTL Communication
TTL control allows direct parallel control of the RCDAT attenuation state, bypassing the micro-controller for high-speed response
(120 nsec typical response).
The TTL controls use 8 control bits buffered by a transparent latch to select the attenuation state. All TTL controls except the TTL
Enable are connected through an internal 10 kΩpull-up resistor to 3.3V, which sets the default state of the buffer to Max
attenuation state with the latch set to “transparent”, allowing any signal on the attenuation control bits to translate immediately
to a change in the attenuation state. When LE is held at logic low the buffer is latched and the RCDAT will maintain the same
attenuation state regardless of the input.
The parallel interface timing requirements are defined by the “TTL Timing” diagram and “Parallel TTL Interface AC Characteristics”
table.
Parallel TTL Interface AC Characteristics
Symbol
Parameter
Min
Max
Units
tSETUP
TTL Enable setup time - used only to start the TTL
control and afterwards not needed.
10 −µs
tPS
LE Setup time - time from when controls C0.25 -
C31.5 are set to LE rising edge.
2 −ns
tLE
LE pulse width
10
−
ns
tHLD
Hold time - the controls C0.25 - C31.5 need to
remain stable after the LE rising edge
10 −ns
Figure 4.7.1: TTL timing diagram

AN-49-005 © 2022 Mini-Circuits
Rev. M | ECO-015752 | 10-Nov-2022 Page 20
For latched parallel programming the Latch Enable (LE) should be held low while changing
attenuation state control values, then pulses high-to-low to latch new attenuation state into
device.
For direct parallel programming, the Latch Enable (LE) line should be pulled high. Changing
attenuation state control values will change device state to new attenuation. Direct mode is ideal
for manual control of the device.
4.7.2. Setup Instructions
To start working with TTL, the user needs to raise momentarily TTL Enable to logic high. The internal micro-controller will go to
sleep mode, disabling other control options (USB, Ethernet, and RS232) and enabling the parallel TTL until power is cycled.
Parameter
Conditions
Min
Typ
Max
Units
Voltage Levels
Logic High (Input)
2.2
-
5
V
Logic Low (Input)
0
-
0.6
Control Current
VCTRL= 0 V
Per Pin
-400
-
-
µA
VCTRL= 3.3 V
0
-
40
VCTRL= 5.0 V
-
-
300
Pin #
Function
1
+5 V
DC
(Optional)
2
GND
3
Not Connected
4
Not Connected
5
TTL Enable
6
LE
7
0.25 dB
8
0.5 dB
9
1.0 dB
10
2.0 dB
11
4.0 dB
12
8.0 dB
13
16.0 dB
14
31.5 dB
15
Not Connected