Model 3250 & 3250T RF Programmable Attenuators dc to 1.0 GHz 1 Watt/75 Ideal for Wireless/Cellular Modem Applications. MAXIMUM CHARACTERISTIC ZERO LOSS (dB): Frequency Range (GHz) dc - 0.5 0.5 - 1.0 Features o Cost Effective design for Wireless/Cellular Applications o Optional TTL or SmartStep Interface o Custom Configurations including bus controlled attenuator subsystems Specifications NOMINAL IMPEDANCE: 75 FREQUENCY RANGE: dc to 1.0 GHz: MAXIMUM SWR: Frequency Range (GHz) SWR dc - 0.5 0.5 - 1.0 1.20 1.30 CELL CONFIGURATIONS: Model Number NO. Cells Attenuation Range/Steps (dB) 3250-63 6 63/1 Cell Increments (dB) 1, 2, 4, 8, 16, 32 Loss (dB) 2.25 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 +70C POWER RATING: 1 watt average, 50 watts peak (5 sec pulse width; 1% duty cycle) CONNECTORS: BNC female connectors per MIL-STD348 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 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 8210A represents a new concept in device control applications for bench test and subsystem designs. The 8210A provides a high-level interface from various industry standard communications interfaces, including IEEE-488 and RS232/RS422/RS485, to the SmartStep's serial Driver Interface Bus. INCREMENTAL ATTENUATION ACCURACY: Frequency Range (GHz) dc - 0.5 0.5 - 1.0 144 10/23/01 Accuracy + 0.3 dB or 2.0% + 0.4 dB or 2.0% 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 8/5/99 CONTROL CONFIGURATION: Non-Volatile Configuration Memory 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: INPUT CURRENT: VIN High= +2.0V minimum VIN Low = +5.0V typical Vcc maximum 0 minimum 0.8 maximum IIN (VIN=2.4 V) = 55 A IIN (VIN=3.85 V) = 280 A 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 microcontrollerbased 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 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 system and sub-system applications. The SmartStep contains non-volatile configuration memory that is used to hold a TTL/CMOS Compatible Digital Interface Single-Chip Microcontroller Relay Drivers +5 V Regulator +12 to +15 V Input To Attenuator Relays EMI Filters Figure 1. SmartStep Driver Circuitry wide variety of attenuator and driver-dependant parameters, 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 25C): Digital Interface: Parameter VIL Low Level input: Specification -0.5 min, 0.8V max VIH 2.0 min, 5.25V max High Level input: IPU Pullup Current Power Supply: VIN Supply Voltage: IIN Supply current: ICELL Supply Current: TEMPERATURE: 50 A min, 400 A max +12.0 to +15.0V 25 mA 150 mA (per cell, switching) -20 to +70C operating -55 to +85C 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). MODEL NUMBER DESCRIPTION: Example: 3250* - XX - X Basic Model Number Attenuation Value (dB) TTL Option (Add -1) Example: 3250-63-1 *Add T to Basic Model Number when ordering SmartStep Control Circuitry. 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 10/23/01 145 PHYSICAL DIMENSIONS: Model 3250: BNC CONNECTORS BOTH ENDS Model 3250 w/TTL Option -1: Control Connector J3 Pin Locations: TTL Conn PIN No. (J3) 3250-63-1 dB (Cell) 1 NC 2 NC 3 32 4 1 5 2 6 4 7 8 8 16 9 COM 10 +Vcc NC = Not Connected NOTE: 146 10/23/01 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 PHYSICAL DIMENSIONS: Model 3250T: BNC CONNECTORS BOTH ENDS 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 10/23/01 147