Surface Mount Digital Step Attenuator 50Ω 0 to 31 dB, 1.0 dB Step DAT-31A+ Series DC to 4.0 GHz The Big Deal • Wideband, operates up to 4 GHz • Immune to latchup • High IP3, 52 dBm CASE STYLE: DG983-2 Product Overview The DAT-31A+ series of 50Ω digital step attenuators provides adjustable attenuation from 0 to 31 dB in 1.0 dB steps. The control is a 5-bit serial/parallel interface, and the attenuators operate with either single positive or dual (positive and negative) supply voltage. DAT-31A+ series models are produced by a unique CMOS process on silicon, offering the performance of GaAs with the advantages of conventional CMOS devices. Key Features Feature Advantages Wideband operation, specified from DC to 4.0 GHz Can be used in multiple applications such as communications, satellite and defense, reducing part count. Serial or parallel interface Models available with serial or parallel interface mode to suit customer demand. Good VSWR, 1.2:1 typ. Eases interfacing with adjacent components and results in low amplitude ripple. Single positive supply models: (Model suffixes: -SP+ and –PP+) +2.3 to +3.6V+ Use of single positive supply simplifies power supply design. An internal negative voltage generator supplies the desired negative voltage. Single positive supply results in excellent spurious performance, -140 dBm typical. Dual supply models: (Model suffixes: -SN+ and –PN+) +2.7 to +3.6V (Positive) and -3.6 to -3.2V (Negative) Dual supply provides spurious-free operation. It also allows fast switching up to 1 MHz (vs. 25 kHz for single supply). Useable over a wide range of supply voltages, +2.3/2.7 to 5.2V Wide range fo positive operating voltages allows the DAT-31A+ Series of models to be used in a wide range of applications. See Application Note AN-70-006 for operation above +3.6V Footprint compatible to DAT-31-XX+ Series (XX=SN/SP/PN/PP) Can fit into existing footprint and provide wideband performance, to 4 GHz instead of 2.4 GHz. Mini-Circuits ® www.minicircuits.com P.O. Box 350166, Brooklyn, NY 11235-0003 (718) 934-4500 [email protected] Page 1 of 8 Digital Step Attenuator 50W DC-4000 MHz 31 dB, 1 dB Step 5 Bit, Serial control interface, Dual Supply Voltage Product Features • Immune to latch up • Excellent accuracy, 0.1 dB Typ • Serial control interface • Fast switching control frequency, up to 1 MHz typ. • Low Insertion Loss • High IP3, +52 dBm Typ • Very low DC power consumption • Excellent return loss, 20 dB Typ • Small size 4.0 x 4.0 mm DAT-31A-SN+ CASE STYLE: DG983-2 +RoHS Compliant The +Suffix identifies RoHS Compliance. See our web site for RoHS Compliance methodologies and qualifications Typical Applications • Base Station Infrastructure • Portable Wireless • CATV & DBS • MMDS & Wireless LAN • Wireless Local Loop • UNII & Hiper LAN • Power amplifier distortion canceling loops General Description The DAT-31A+ series of 50Ω digital step attenuators provides adjustable attenuation of 0 to 31 dB in 1.0 dB steps. The control is a 5-bit serial interface, and the attenuators operate with dual (positive and negative) supply voltage. DAT-31A-SN+ is produced using a CMOS process on silicon, offering the performance of GaAs with the advantages of conventional CMOS devices. Simplified Schematic RF Input 16dB 8dB 4dB 2dB 1dB RF Out Digital Serial Control Mini-Circuits ® www.minicircuits.com P.O. Box 350166, Brooklyn, NY 11235-0003 (718) 934-4500 [email protected] REV. C M164761 DAT-31A-SN+ RS/TH/CP 171110 Page 2 of 8 DAT-31A-SN+ Digital Step Attenuator RF Electrical Specifications (Note1), DC-4000 MHz, TAMB=25°C, VDD=+3V, VSS=-3.2V Parameter Freq. Range (GHz) Min. Typ. DC-1 — 0.02 0.1 1-2.4 — 0.05 0.15 0.1 0.25 Accuracy @ 1 dB Attenuation Setting 2.4-4 Accuracy @ 2 dB Attenuation Setting DC-1 — 0.05 0.15 1-2.4 — 0.15 0.25 0.15 0.35 2.4-4 Accuracy @ 4 dB Attenuation Setting DC-1 — 0.07 0.2 1-2.4 — 0.15 0.25 0.23 0.5 2.4-4 Accuracy @ 8 dB Attenuation Setting DC-1 — 0.03 0.2 1-2.4 — 0.15 0.5 0.6 0.8 0.3 2.4-4 Accuracy @ 16 dB Attenuation Setting DC-1 — 0.1 1-2.4 — 0.15 0.7 1.1 1.45 2.4-4 dB dB dB dB dB — 1.3 1.9 1-2.4 — 1.6 2.4 2.4-4 — 2.1 3.0 DC-4 — +52 — dBm DC-4 — +24 — dBm 10 kHz to 50 MHz — — See Fig. 1 >50 MHz — DC-1 1-2.4 2.4-4 — — — Input IP3 (note 2) (at Min. and Max. Attenuation) (note 2) Input Operating Power Units DC-1 Insertion Loss (note 1) @ all attenuator set to 0dB Input Power @ 0.2dB Compression (at Min. and Max. Attenuation) Max. VSWR dB +24 1.2 1.2 1.4 1.5 1.6 1.9 dBm :1 Notes: 1. Tested on Evaluation Board TB-342, See Figure 3. 2. Insertion loss values are de-embedded from test board Loss (test board’s Insertion Loss: 0.10dB @100MHz, 0.35dB @1000MHz, 0.60dB @2400MHz, 0.75dB @4000MHz). 3. Input IP3 and 1dB compression degrade below 1 MHz. Input power not to exceed max operating specification for continuous operation. DC Electrical Specifications Switching Specifications Parameter Min. Typ. Max. Units Vdd, Supply Voltage 2.7 3 3.6 (Note 4) V Vss, Supply Voltage -3.6 -3.3 -3.2 Min. Typ. Max. Units V Switching Speed, 50% Control to 0.5dB of Attenuation Value — 1.0 — µSec Switching Control Frequency — 1.0 — MHz Idd Supply Current — — 100 µA Iss Supply Current — 16 40 µA Control Input Low -0.3 — +0.6 V Control Input High 1.17 — 3.6 V — — 20 (Note 5) µA Control Current Parameter 4. For operation above +3.6V, see Application Note AN-70-006 5. Except, 30µA typ for C16 at +3.6V Absolute Maximum Ratings(Note 6,7) Parameter Ratings Operating Temperature Storage Temperature Vdd Vss Voltage on any control input Input Power Thermal Resistance -40°C to 105°C -65°C to 150°C -0.3V Min., 5.5V Max. -3.6V Min., 0.3V Max. -0.3V Min., 3.6V Max. +30dBm 37°C/W Figure 1. Max Input Operating Power vs Frequency 6. Permanent damage may occur if any of these limits are exceeded. 7. Operation between max operating and absolute max input power will result in reduced reliability. Mini-Circuits ® www.minicircuits.com P.O. Box 350166, Brooklyn, NY 11235-0003 (718) 934-4500 [email protected] Page 3 of 8 DAT-31A-SN+ Serial Digital Step Attenuator Not connected N/C 8 Not connected VDD 9 Positive Supply Voltage GND 10 Ground connection GND 11 Ground connection VSS 12 Negative Supply Voltage VDD 13 Positive Supply Voltage (Note 8) RF out 14 RF out port (Note 1) C8 15 Control for attenuation bit, 8 dB (Note 4) C4 16 Control for attenuation bit, 4 dB (Note 4) LE 5 Notes: 1. Both RF ports must be held at 0VDC or DC blocked with an external series capacitor. 2. Latch Enable (LE) has an internal 2MW to internal positive supply voltage. C2 C4 GND C2 C4 18 17 16 Paddle ground (Note 5) MCL C16 1 RFin 2 N/C 3 DS50 2x2mm Paddle ground GND 4 3. Place a 10KW resistor in series, as close to pin as possible to avoid freq. resonance. LE 4. Refer to Power-up Control Settings. 5. The exposed solder pad on the bottom of the package (See Pin configuration) must be grounded for proper device operation. 6. This pin has an internal 200 kΩ resistor to ground. 7. Place a shunt 10 kΩ resistor to ground. 5 8 Not connected (Note 7) PUP2 20 Paddle 16 17 VDD N/C GND Pin 1 Index N/C Control for attenuation bit, 1 dB (Note 4) C1 19 19 Ground Connection C1 20 Control for attenuation bit, 2 dB (Note 4) 18 14 RFout 13 VDD 12 VSS 11 GND 15 C8 14 RFout 13 GND 12 VSS 11 GND Parallel 7 17 C8 Device Marking 6 C2 GND 9 Positive Supply Voltage 7 4 VDD 6 3 6 VDD N/C Data Clock 15 GND 10 Latch Enable Input (Note 2) 2x2mm Paddle ground 9 5 2 10 LE RFin VDD Serial Interface clock input GND 4 1 GND Clock C16 18 Serial Interface data input (Note 3) 8 3 N/C Data C1 RF in port (Note 1) N/C Control for Attenuation bit, 16dB (Notes 3,4,6) 2 19 1 7 C16 RF in N/C Description VDD Pin Number PUP1 Function 20 Pin Configuration (Top View) Pin Description 8. When VDD<=3.6V this pin may be connected directly to VDD, when 3.6V< VDD <=5.2V need to use a voltage divider to reduce voltage on this pin to a voltage in the range +1.17 to 3.6V. See Application note AN-70-006. Mini-Circuits ® www.minicircuits.com P.O. Box 350166, Brooklyn, NY 11235-0003 (718) 934-4500 [email protected] Page 4 of 8 DAT-31A-SN+ Digital Step Attenuator Simplified Schematic RF Input 16dB 8dB 4dB 2dB RF Out 1dB Digital Serial Control The DAT-31A-SN+ serial interface consists of 5 control bits that select the desired attenuation state, as shown in Table 1: Truth Table Table 1. Truth Table Attenuation State C16 C8 C4 C2 C1 Reference 0 0 0 0 0 1 (dB) 0 0 0 0 1 2 (dB) 0 0 0 1 0 4 (dB) 0 0 1 0 0 8 (dB) 0 1 0 0 0 16 (dB) 1 0 0 0 0 31 (dB) 1 1 1 1 1 Note: Not all 32 possible combinations of C1 - C16 are shown in table The serial interface is a 5-bit serial in, parallel-out shift register buffered by a transparent latch. It is controlled by three CMOS-compatible signals: Data, Clock, and Latch Enable (LE). 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 LE input controls the latch. When LE is HIGH, the latch is transparent and the contents of the serial shift register control the attenuator. 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 attenuator value 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 Figure 2 (Serial Interface Timing Diagram) and Table 2 (Serial Interface AC Characteristics). Figure 2: Serial interface Timing Diagram LE Symbol fclk Clock Data Table 2. Serial Interface AC Characteristics MSB LSB tSDSUP tSDHLD tLESUP tLEPW Parameter Min. Serial data clock frequency (Note 1) Max. Units 10 MHz tclkH Serial clock HIGH time 30 ns tclkL Serial clock LOW time 30 ns tLESUP LE set-up time after last clock falling edge 10 ns tLEPW LE minimum pulse width 30 ns Serial data set-up time before clock rising edge 10 ns tSDSUP Serial data hold time 10 ns after clock falling edge Note 1. fclk verified during the functional pattern test. Serial programming sections of the functional pattern are clocked at 10MHz to verify fclk specification. tSDHLD Mini-Circuits ® www.minicircuits.com P.O. Box 350166, Brooklyn, NY 11235-0003 (718) 934-4500 [email protected] Page 5 of 8 DAT-31A-SN+ Digital Step Attenuator The DAT-31A-SN+, uses a common 5-bit serial word format, as shown in Table 3: 5-Bit attenuator Serial Programming Register Map. The first bit, the MSB, corresponds to the 16 dB Step and the bit B1 corresponds to the 1 dB step. Table 3. 6-Bit attenuator Serial Programming Register Map B5 B4 B3 B2 B1 B0 C16 C8 C4 C2 C1 0 MSB (first in) LSB (last in) Note: The stop bit (B0) must always be low to present the attenuator from entering an unknown state. Power-up Control Settings The DAT-31A-SN+ always assumes a specifiable attenuation setting on power-up, allowing a known attenuation state to be established before an initial serial control word is provided. When the attenuator powers up, the six control bits are set to whatever data is present on the six data inputs (C1 to C16). This allows any one of the 32 attenuation settings to be specified as the power-up state. Mini-Circuits ® www.minicircuits.com P.O. Box 350166, Brooklyn, NY 11235-0003 (718) 934-4500 [email protected] Page 6 of 8 DAT-31A-SN+ Digital Step Attenuator TB-342 Bill of Materials N1-N6, N11, N12, N15 & N18 Resistor 0603 10 KOhm +/- 1% N26 Resistor 0603 0 Ohm N10, N16, N17, N20 NPO Capacitor 0603 100pF +/- 5% & N23 N21 & N22 Tantalum Capacitor 0805 100nF +/- 10% N19 Hex Invert Schmitt Trigger MSL1 Notes 1. Both RF ports must be held at 0VDC or DC blocked with an external series capacitor. 2. Test Board TB-342 is designed for operation for VDD=2.3 to 3.6V. For operation over 3.6V to 5.2V, See Application Note AN-70-006 3. VDD=Vdd Fig 3. Evaluation Board Schematic, TB-342, used for characterization (DUT not soldered on TB-342) Test Equipment Measurement Conditions For Insertion Loss, Isolation and Return Loss: Agilent’s E5071C Network Analyzer & E3631A Power Supply. For Compression: Agilent’s N9020A Signal Analyzer, E8247C RF Generator, E3631A Power Supply & U2004A Power Sensor. For Input IP3: Agilent’s N9020A Signal Analyzer, N5181A Signal Generators, E3631A Power Supply, U2004A Power Sensor. For Spurs: Agilent N5181A Signal Generator, E4440A Spectrum Analyzer. For Switching Time: Agilent’s N5181A Signal Generator, 81110A Pulse Generator, 54832B Oscilloscope, E3631A Power Supply. For Max Control Frequency: Agilent’s N5181A Signal Generator, N9020A Signal Analyzer, E3631A Power Supply, 81110A Pulse Generator. For Insertion Loss, Isolation and Return Loss: VDD=+2.7/+3/+5.5V &Pin=0dBm VSS=-3.2/-3.6V For Compression: Pin=0/+24dBm. VDD=+3V, VSS=-3V For Input IP3: Pin=+10dBm/tone. Tone spacing: 0.1 MHz to 1 MHz RF Freq and 1 MHz to 4200 MHz RF Freq, VDD=+3V, VSS=-3V For Spurs: RF IN at 1000MHz and -20dBm. VDD=+3V For Switching Time: RF Freq=501MHz/0dBm, Pulse for LE=1Hz/0/+3.4V, Delay=500ms, Width=500ms. VDD=+3V & VSS=-3V For Max Control Frequency: RF Freq=501MHz, 0dBm. VDD=+3V, VSS=-3V Mini-Circuits ® www.minicircuits.com P.O. Box 350166, Brooklyn, NY 11235-0003 (718) 934-4500 [email protected] Page 7 of 8 DAT-31A-SN+ Digital Step Attenuator Additional Detailed Technical Information additional information is available on our dash board. To access this information click here Data Table Performance Data Swept Graphs S-Parameter (S2P Files) Data Set (.zip file) Case Style DG983-2 Plastic package, exposed paddle, lead finish: NiPdAu Tape & Reel F87 Standard quantities available on reel 7” reels with 20, 50, 100 or 200 devices 13” reels with 3K devices Suggested Layout for PCB Design PL-190 Evaluation Board TB-342 Environmental Ratings ENV33T1 ESD Rating Human Body Model (HBM): Class 1C (1000 to <2000V) in accordance with MIL-STD-883 method 3015 MSL Rating Moisture Sensitivity: MSL1 in accordance with IPC/JEDEC J-STD-020D MSL Test Flow Chart Start Visual Inspection Electrical Test SAM Analysis Reflow 3 cycles, 260°C Soak 85°C/85RH 168 hours Bake at 125°C, 24 hours Visual Inspection Electrical Test SAM Analysis Finish Additional Notes A. Performance and quality attributes and conditions not expressly stated in this specification document are intended to be excluded and do not form a part of this specification document. B. Electrical specifications and performance data contained in this specification document are based on Mini-Circuit’s applicable established test performance criteria and measurement instructions. C. The parts covered by this specification document are subject to Mini-Circuits standard limited warranty and terms and conditions (collectively, “Standard Terms”); Purchasers of this part are entitled to the rights and benefits contained therein. For a full statement of the Standard Terms and the exclusive rights and remedies thereunder, please visit Mini-Circuits’ website at www.minicircuits.com/MCLStore/terms.jsp Mini-Circuits ® www.minicircuits.com P.O. Box 350166, Brooklyn, NY 11235-0003 (718) 934-4500 [email protected] Page 8 of 8