3250-63-1 - Weinschel Corp. - Datasheet.Global

5305 Spectrum Drive, Frederick, MD 21703-7362 TEL: 301-846-9222, 800-638-2048 Fax: 301-846-9116

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Model 3250 & 3250T dc to 1.0 GHz

RF Programmable Attenuators 1 Watt/75 ΩΩ

Ideal for Wireless/Cellular Modem Applications.

Features

oCost Effective design for Wireless/Cellular

Applications

oOptional TTL or SmartStep Interface

oCustom Configurations including bus controlled

attenuator subsystems

Specifications

NOMINAL IMPEDANCE: 75 Ω

FREQUENCY RANGE: dc to 1.0 GHz:

CELL CONFIGURATIONS:

Model NO. Attenuation Cell

Number Cells Range/Steps Increments

(dB) (dB)

3250-63 6 63/1 1, 2, 4, 8, 16, 32

INCREMENTAL ATTENUATION ACCURACY:

Frequency Accuracy

Range (GHz)

dc - 0.5 + 0.3 dB or 2.0%

0.5 - 1.0 + 0.4 dB or 2.0%

MAXIMUM SWR:

Frequency Range (GHz) SWR

dc - 0.5 1.20

0.5 - 1.0 1.30

Frequency Range (GHz) Loss (dB)

dc - 0.5 2.25

0.5 - 1.0 4.75

RATED SWITCH LIFE: 5 million operations per cell (typ)

SWITCHING TIME: 8 msec. maximum @ nominal rated

voltage.

CYCLING RATE: 5 Hz maximum

OPERATING VOLTAGE: +11V to +16V

+12V to +17V (TTL opt -1)

OPERATING CURRENT: 16 mA maximum per cell

TEMPERATURE RANGE (Operating): -40 to +70°C

POWER RATING: 1 watt average, 50 watts peak (5 µsec

pulse width; 1% duty cycle)

CONNECTORS: BNC female connectors per MIL-STD-

348 interface dimensions - mate nondestructively with

MIL-C-39012 connectors.

CONTROL TERMINALS: 0.040 inch. (1 mm) diameter

solderable leads

CONSTRUCTION:

Housing: Aluminum

Connectors: Nickel plated brass body and

beryllium copper contacts.

WEIGHT: 3250 140 g (4.5 oz)

3250T 189 g (4.9 oz)

ACCESSORIES

SmartStep Interface: The Model 8210A SmartStep

Interface provides a flexible, low cost solution for the oper-

ation of programmable step attenuators and other

electromechanical devices under computer control.

Designed to interface to Weinschel's new line of SmartStep

programmable attenuators, the 8210A represents a new

concept in device control applications for bench test and

subsystem designs. The 8210A provides a high-level inter-

face from various industry standard communications

interfaces, including IEEE-488 and RS232/RS422/RS485,

to the SmartStep's serial Driver Interface Bus.

MAXIMUM CHARACTERISTIC ZERO LOSS (dB):

8/5/99

MODEL NUMBER DESCRIPTION:

Example:

3250* - XX - X

*Add T to Basic Model Number when ordering SmartStep

Control Circuitry.

Basic

Model

Number

Attenuation

Value (dB)

TTL Option

(Add -1)

Example: 3250-63-1

5305 Spectrum Drive, Frederick, MD 21703-7362 TEL: 301-846-9222, 800-638-2048 Fax: 301-846-9116

web: www.weinschel.com email: sales@weinschel.com

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10/23/01

Figure 1. SmartStep Driver Circuitry

CONTROL CONFIGURATION:

Standard Unit: One terminal is connected to case ground

and the remaining terminals are provided for activation of

individual cells. Attenuation is fail-safe to "0" setting in the

absence of a control voltage. Application of a voltage (+) to

a particular cell causes it to switch to the attenuate position.

Units with TTL Option: Units with this options are supplied

with a very low profile connectorized TTL interface board

mounted directly to the control terminals. This TTL interface

option is available with a 10 pin ribbon cable connector and

is supplied with a mating connector. Refer to Physical

Dimensions for mating connector pin/wiring details. Two

wires are specified for supply voltage and ground. The

remaining wires will accept TTL control signals to activate or

de-activate a particular attenuation cell. A TTL high will

energize a cell to the high attenuation state, whereas a TTL

low will maintain a cell in its zero attenuation state.

To order 3250 Series Attenuators with this option add -1 to

basic model number for ribbon cable connector. Example:

Model 3250-63 with a TTL interface would be 3250-63-1.

Note: Control is non-latching and requires a continuous

control signal for the period of time in which attenuation is

required.

TTL DRIVER SPECIFICATIONS:

INTERFACE CONNECTOR: Option -1: 10 pin .025 square

post header on .1 center, mates with Amp connector

746285-1 or equivalent

INPUT VOLTAGE: VIN High= +2.0V minimum

+5.0V typical

Vcc maximum

VIN Low = 0 minimum

0.8 maximum

INPUT CURRENT: IIN (VIN=2.4 V) = 55 µA

IIN (VIN=3.85 V) = 280 µA

SUPPLY CURRENT: ICC=25 mA maximum per cell

SUPPLY VOLTAGE: VCC=+12.0 to +15 V

TEMPERATURE RANGE (Operating): -40 to +70 °C

Units with SmartStep driver Circuitry (Figure 1): The

SmartStep attenuators feature an internal microcontroller-

based driver that provides a TTL-level digital interface for

control of the attenuator relays. This card simplifies oper-

ation 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 I2C bus. The parallel mode provides 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 variety of methods,

such as a TTL-level digital output port, or mechanical toggle

switches. The I2C 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 sys-

tem and sub-system applications. The SmartStep contains

non-volatile configuration memory that is used to hold a

Non-Volatile

Configuration

Memory

Single-Chip

Microcontroller

Relay

Drivers

TTL/CMOS

Compatible

Digital Interface

+12 to

+15 V

Input

Attenuator

Relays

EMI

Filters

+5 V

Regulator

wide variety of attenuator and driver-dependant parame-

ters, including serial number, attenuator cell dB values,

relay configurations, and switching requirements, which are

all accessable via the I2C interface.

SmartStep Driver Interface Specifications:

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:

Parameter Specification

VILLow Level input: -0.5 min, 0.8V max

VIH High Level input: 2.0 min, 5.25V max

IPU Pullup Current 50 µA min, 400 µA max

Power Supply:

VIN Supply Voltage: +12.0 to +15.0V

IIN Supply current: 25 mA

ICELL Supply Current: 150 mA (per cell, switching)

TEMPERATURE: -20° to +70°C operating

-55° to +85°C nonoperating

INTERFACE CONNECTOR: 14 pin .025 square post

header on .1 center. Mates with Amp connector 746285-2 or

equivalent (one mating connector included with each unit).

5305 Spectrum Drive, Frederick, MD 21703-7362 TEL: 301-846-9222, 800-638-2048 Fax: 301-846-9116

web: www.weinschel.com email: sales@weinschel.com

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10/23/01

BNC CONNECTORS

BOTH ENDS

PHYSICAL DIMENSIONS:

Model 3250:

Model 3250 w/TTL Option -1:

TTL Conn 3250-63-1

PIN No. (J3) dB (Cell)

1NC

2NC

332

816

9 COM

10 +Vcc

NC = Not Connected

Control Connector J3 Pin Locations:

NOTE: All dimensions are given in mm (inches) and are maximum, unless otherwise specified.

5305 Spectrum Drive, Frederick, MD 21703-7362 TEL: 301-846-9222, 800-638-2048 Fax: 301-846-9116

web: www.weinschel.com email: sales@weinschel.com

147

10/23/01

BNC CONNECTORS

BOTH ENDS

PHYSICAL DIMENSIONS:

Model 3250T:

NOTE: All dimensions are given in mm (inches) and are maximum, unless otherwise specified.