IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz GENERAL DESCRIPTION FEATURES The IDTF2255 is a low insertion loss Voltage Variable RF Attenuator (VVA) designed for a multitude of wireless and other RF applications. This device covers a broad frequency range from 1MHz to 3000MHz. In addition to providing low insertion loss, the IDTF2255 provides excellent linearity performance over its entire voltage control and attenuation range. • • • • • • • The F2255 uses a single positive supply voltage of 3.15V to 5.25V. Other features include the VMODE pin allowing either positive or negative voltage control slope vs attenuation and multi-directional operation meaning the RF input can be applied to either RF1 or RF2 pins. Control voltage ranges from 0V to 3.6V using either positive or negative control voltage slope. • • • • • COMPETITIVE ADVANTAGE Low Insertion Loss: 1.1dB @ 500MHz Typical / Min IIP3: 60dBm / 46dBm Typical / Min IIP2: 98dBm / 74dBm 33dB Attenuation Range Bi-directional RF ports +36dBm Input P1dB compression VMODE pin allows either positive or negative control response Linear-in-dB attenuation characteristic Supply voltage: 3.15V to 5.25V VCTRL range: 0V to 3.6V using 5V supply +105°C max operating temperature 3x3, 16-pin QFN package DEVICE BLOCK DIAGRAM IDTF2255 provides extremely low insertion loss and superb IP3, IP2, Return Loss and Slope Linearity across the control range. Comparing to competitive VVAs this device is better as follows: Operation down to 1MHz Insertion Loss @ 500MHz: 1.1dB Maximum Attenuation Slope: 33dB/Volt Minimum Output IP3: 35dBm Minimum Input IP2: 74dBm High Operating Temperature: +105°C ORDERING INFORMATION APPLICATIONS • • • • • • • • • • • • • Omit IDT prefix Base Station 2G, 3G, 4G, Portable Wireless Repeaters and E911 systems Digital Pre-Distortion Point to Point Infrastructure Public Safety Infrastructure Satellite Receivers and Modems WIMAX Receivers and Transmitters Military Radios covering HF, VHF, UHF RFID handheld and portable readers Cable Infrastructure Wireless LAN Test / ATE Equipment Voltage Variable RF Attenuator Tape & Reel 0.9 mm height package IDTF2255NLGK8 Green RF product Line PART# MATRIX 1 IIP3 Part# RF Freq Range (MHz) Insertion Loss (dB) (dBm) Pinout Compatibility F2250 50 - 6000 1.4 (at 2GHz) +65 RFMD F2255 1 - 3000 1.1 (at 500MHz) +60 F2258 50 - 6000 1.4 (at 2GHz) +65 Hittite REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz ABSOLUTE MAXIMUM RATINGS Parameter / Condition VDD to GND VMODE to GND VCTRL to GND VDD = 0V to 5.25V RF1, RF2 to GND RF1 or RF2 Input Power applied for 24 hours maximum (VDD applied @ 2GHz and Tc=+85°C) RF1 or RF2 Continuous Operating Power Maximum Junction Temperature Storage Temperature Range Lead Temperature (soldering, 10s) ESD Voltage– HBM (Per ESD STM5.1-2007) ESD Voltage – CDM (Per ESD STM5.3.1-2009) Symbol VDD VMODE VCTRL VRF Min -0.3 -0.3 -0.3 -0.3 Max 5.5 Minimum ( VDD, 3.9 ) Minimum ( VDD, 4.0 ) 0.3 Units V V V V PMAX24 30 dBm PMAX_OP TJMAX TST TLEAD VESDHBM VESDCDM See Figure 1 +150 +150 +260 Class 2 Class C3 dBm °C °C °C -65 FIGURE 1: MAXIMUM OPERATING RF INPUT POWERS VS. RF FREQUENCY Stresses above those listed above may cause permanent damage to the device. Functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. PACKAGE THERMAL AND MOISTURE CHARACTERISTICS ΘJA (Junction – Ambient) ΘJC (Junction – Case) The Case is defined as the exposed paddle Moisture Sensitivity Rating (Per J-STD-020) Voltage Variable RF Attenuator 2 80.6°C/W 5.1°C/W MSL 1 REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz IDTF2255 OPERATING CONDITIONS Parameter Operating Freq Range Supply Voltage Symbol VIH VMODE Logic Condition FRF VDD VDD > 3.9V VDD = 3.15 to 3.9V VIL VCTRL Range VCTRL Supply Current Logic Current ICTRL Current RF Operating Power VDD = 3.9V to 5.25V VDD = 3.15V to 3.9V IMODE ICTRL Typ 1 3.15 1.17 1.17 0 0 0 0.801 -1.0 -1.0 IDD 3 Min 1.15 PMAXCW RF1 Port Impedance ZRF1 50 RF2 Port Impedance Operating Temperature Range ZRF2 50 TCASE Exposed Paddle Temperature -40 Max Units 3000 5.25 3.62 VDD -0.3V 0.63 3.6 VDD-0.3 MHz V 1.50 24 10 mA µA µA See Figure 1 dBm V V Ω +105 °C Operating Conditions Notes: 1 – Items in min/max columns in bold italics are Guaranteed by Test. 2 – Items in min/max columns that are not bold/italics are Guaranteed by Design Characterization. 3 – Refer to the Maximum Operating RF Input Power vs. RF Frequency curves in Figure 1. Voltage Variable RF Attenuator 3 REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz IDTF2255 SPECIFICATIONS Refer to EVKit / Applications Circuit, VDD = +3.3V, TC = +25°C, signals applied to RF1 input, FRF = 500MHz, minimum attenuation, PIN = 0dBm for small signal parameters, +20dBm for single tone linearity tests, +20dBm per tone for two tone tests, two tone delta frequency = 80MHz, PCB board traces and connector losses are de-embedded unless otherwise noted. Refer to Typical Operating Curves for performance over entire frequency band. Parameter Insertion Loss, IL Maximum attenuation Symbol AMIN AMAX Φ∆MAX Insertion Phase ∆ Φ∆MID Input 1dB Compression3 S11 Minimum RF2 Return Loss over control voltage range S22 Input IP3 Input IP3 over Attenuation Minimum Output IP3 IIP3 IIP3ATTEN OIP3MIN Minimum Input IP2 Input IH2 Input IH3 Settling Time Min Typ Max Units 1.7 1 33 1.1 34.6 dB dB At 36dB attenuation relative to Insertion Loss At 18dB attenuation relative to Insertion Loss 27 deg 8 P1dB Minimum RF1 Return Loss over control voltage range Input IP2 Condition Minimum Attenuation IIP2 IIP2MIN HD2 HD3 TSETTL0.1dB 20MHz 500MHz 2000MHz 3000MHz 20MHz 500MHz 2000MHz 3000MHz All attenuation settings Maximum attenuation PIN + IM2dBC, IM2 term is F1+F2 All attenuation settings PIN + H2dBc PIN + (H3dBc/2) Any 1dB step in the 0dB to 33dB control range 50% VCTRL to RF settled to within ± 0.1dB 442 36 23 22 23 30 23 22 23 24 60 46 35 dBm dB dB dBm 98 dBm 74 82 49 dBm dBm dBm 15 µSec Specification Notes: 1 – Items in min/max columns in bold italics are Guaranteed by Test 2 – Items in min/max columns that are not bold/italics are Guaranteed by Design Characterization. 3 – The input 1dB compression point is a linearity figure of merit. Refer to Absolute Maximum Ratings section along with Figure 1 for the maximum RF input power vs. RF frequency. Voltage Variable RF Attenuator 4 REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz TYPICAL OPERATING CURVES Unless otherwise noted, the following conditions apply: • • • • • • • • VDD = +3.3V or +5.0V TC = +25ºC VMODE = 0V RF trace and connector losses are de-embedded for S-parameters Pin = 0dBm for all small signal tests Pin = +20dBm for single tone linearity tests (RF1 port driven) Pin = +20dBm/tone for two tone linearity tests (RF1 port driven) Two tone frequency spacing = 80MHz Voltage Variable RF Attenuator 5 REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz TYPICAL OPERATING CONDITIONS [S2P BROADBAND PERFORMANCE] (-1-) Attenuation vs. VCTRL Attenuation vs. Frequency 25C / 25C / 25C / 25C / 25C / 25C / 25C / 25C / 25C / Attenuation (dB) -5 -10 -15 -20 0 10MHz 50MHz 100MHz 250MHz 500MHz 900MHz 1200MHz 1900MHz 2700MHz -5 Attenuation (dB) 0 -25 -30 -35 -10 -15 -20 -25 -30 -35 25C / 0.0V 25C / 1.2V 25C / 1.8V -40 25C / 1.0V 25C / 1.6V 25C / 2.8V -45 -40 0.0 0.4 0.8 1.2 1.6 2.0 2.4 0 2.8 500 1000 Min. & Max. Attenuation vs. Frequency 4 -16 -40C / 0.0V 25C / 0.0V 105C / 0.0V -40C / 2.8V 25C / 2.8V 105C / 2.8V -4 -24 -6 -32 -8 0 500 1000 1500 2000 2500 2500 3000 -40C / 11MHz -40C / 251MHz -40C / 900MHz 105C / 11MHz 105C / 251MHz 105C / 900MHz 3 2 1 0 -1 -2 -3 -40 3000 0.0 0.4 0.8 1.2 1.6 2.0 2.4 VCTRL (V) Frequency (MHz) Voltage Variable RF Attenuator 2000 Attenuation Delta to 25C vs. VCTRL -8 Attenuation Error (dB) 0 -2 1500 Frequency (MHz) VCTRL (Volts) Attenuation (dB) 25C / 0.8V 25C / 1.4V 25C / 2.2V 6 REV O, July 2015 2.8 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz TYPICAL OPERATING CURVES [S2P vs. VCTRL] (-2-) Attenuation vs. VCTRL Attenuation Slope vs. VCTRL 25C Attenuation (dB) -5 40 4MHz 25C 15MHz Attenuation Slope (dB/V) 0 60MHz -10 200MHz 600MHz -15 1200MHz -20 2100MHz -25 -30 -35 -40 35 30 25 20 15 4MHz 60MHz 600MHz 2100MHz 10 5 0 0.0 0.4 0.8 1.2 1.6 2.0 2.4 2.8 0.6 0.8 1.0 1.2 VCTRL (V) 1.6 1.8 2.0 2.2 RF2 Return Loss vs. VCTRL 0 0 -10 25C 15MHz 200MHz 1200MHz 4MHz 60MHz 600MHz 2100MHz -5 RF2 Return Loss (dB) 4MHz 60MHz 600MHz 2100MHz -5 RF1 Return Loss (dB) 1.4 VCTRL (V) RF1 Return Loss vs. VCTRL -15 -20 -25 -30 -35 -10 25C 15MHz 200MHz 1200MHz -15 -20 -25 -30 -35 -40 -40 0.0 0.4 0.8 1.2 1.6 2.0 2.4 2.8 0.0 0.4 0.8 1.2 VCTRL (V) 4MHz 15MHz 60MHz 200MHz 600MHz 1200MHz 2100MHz 70 60 50 40 110 (positive phase = electrically shorter) 30 25C 20 10 0 0.0 0.4 0.8 1.2 1.6 2.0 2.4 4MHz 200MHz 2100MHz 90 2.4 2.8 15MHz 600MHz 60MHz 1200MHz 25C 70 50 30 10 -10 0.6 2.8 0.8 1.0 1.2 1.4 1.6 1.8 2.0 VCTRL (V) VCTRL (V) Voltage Variable RF Attenuator 2.0 Insertion Phase Slope vs. VCTRL Insertion Phase Slope (deg/V) 80 1.6 VCTRL (V) Insertion Phase ∆ vs. VCTRL Insertion Phase ∆ (deg) 15MHz 200MHz 1200MHz 7 REV O, July 2015 2.2 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz TYPICAL OPERATING CONDITIONS [S2P VS. VCTRL & TEMPERATURE] (-3-) Attenuation Response vs. VCTRL 0 45 -10 -15 -20 Attenuation Slope (dB/V) -40C / 15MHz -40C / 500MHz -40C / 1200MHz 25C / 15MHz 25C / 500MHz 25C / 1200MHz 105C / 15MHz 105C / 500MHz 105C / 1200MHz -5 Attenuation (dB) Attenuation Slope vs. VCTRL -25 -30 -35 -40 -40C / 15MHz -40C / 500MHz -40C / 1200MHz 25C / 15MHz 25C / 500MHz 25C / 1200MHz 105C / 15MHz 105C / 500MHz 105C / 1200MHz 40 35 30 25 20 15 10 5 0 0.0 0.4 0.8 1.2 1.6 2.0 2.4 2.8 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 VCTRL (V) VCTRL (V) RF1 Return Loss vs. VCTRL RF2 Return Loss vs. VCTRL 0 -10 -15 -20 -25 -30 -35 -10 -15 -20 -25 -30 -35 -40 -40 0.0 0.4 0.8 1.2 1.6 2.0 2.4 0.0 2.8 30 Insertion Phase Slope (deg/V) 40 1.2 1.6 80 -40C / 15MHz (positive phase = electrically shorter) -40C / 500MHz -40C / 1200MHz 25C / 15MHz 25C / 500MHz 25C / 1200MHz 105C / 15MHz 105C / 500MHz 105C / 1200MHz 50 0.8 2.0 2.4 2.8 Insertion Phase Slope vs. VCTRL Insertion Phase ∆ vs. VCTRL 60 0.4 VCTRL (V) VCTRL (V) Insertion Phase ∆ (deg) -40C / 15MHz -40C / 500MHz -40C / 1200MHz 25C / 15MHz 25C / 500MHz 25C / 1200MHz 105C / 15MHz 105C / 500MHz 105C / 1200MHz -5 RF2 Return Loss (dB) -5 RF1 Return Loss (dB) 0 -40C / 15MHz -40C / 500MHz -40C / 1200MHz 25C / 15MHz 25C / 500MHz 25C / 1200MHz 105C / 15MHz 105C / 500MHz 105C / 1200MHz 20 10 -40C / 15MHz -40C / 500MHz -40C / 1200MHz 25C / 15MHz 25C / 500MHz 25C / 1200MHz 105C / 15MHz 105C / 500MHz 105C / 1200MHz 70 60 50 40 30 20 10 0 0 0.0 0.4 0.8 1.2 1.6 2.0 2.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 2.8 VCTRL (V) VCTRL (V) Voltage Variable RF Attenuator 8 REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz TYPICAL OPERATING CONDITIONS [S2P VS. ATTENUATION & TEMPERATURE] (-4-) RF1 Return Loss vs. Attenuation RF1 Return Loss vs. Attenuation 0 RF1 Return Loss (dB) -5 -10 4MHz 60MHz 600MHz 2100MHz 0 25C / 15MHz 25C / 200MHz 25C / 1200MHz -40C / 15MHz -40C / 500MHz -40C / 1200MHz 25C / 15MHz 25C / 500MHz 25C / 1200MHz 105C / 15MHz 105C / 500MHz 105C / 1200MHz -5 RF1 Return Loss (dB) 25C / 25C / 25C / 25C / -15 -20 -25 -30 -10 -15 -20 -25 -30 -35 -35 -40 -40 0 4 8 12 16 20 24 28 32 0 36 4 8 RF2 Return Loss vs. Attenuation -10 -40C / 15MHz -40C / 1200MHz 25C / 500MHz 105C / 15MHz 105C / 1200MHz -5 -15 -20 -25 -30 28 32 36 -10 -40C / 500MHz 25C / 15MHz 25C / 1200MHz 105C / 500MHz -15 -20 -25 -30 -35 -35 -40 -40 0 4 8 12 16 20 24 28 32 0 36 4 8 Insertion Phase ∆ vs. Attenuation 80 25C / 15MHz 60 25C / 60MHz 25C / 200MHz 50 25C / 600MHz 25C / 1200MHz 40 20 24 28 32 36 28 32 36 60 Insertion Phase ∆ (deg) 70 16 Insertion Phase ∆ vs. Attenuation (positive phase = electrically shorter) 25C / 4MHz 12 Attenuation (dB) Attenuation (dB) Insertion Phase ∆ (deg) 24 0 25C / 15MHz 25C / 200MHz 25C / 1200MHz RF2 Return Loss (dB) RF2 Return Loss (dB) -5 20 RF2 Return Loss vs. Attenuation 0 4MHz 60MHz 600MHz 2100MHz 16 Attenuation (dB) Attenuation (dB) 25C / 25C / 25C / 25C / 12 25C / 2100MHz 30 20 10 -40C / 15MHz -40C / 500MHz -40C / 1200MHz 25C / 15MHz 25C / 500MHz 25C / 1200MHz 105C / 15MHz 105C / 500MHz 105C / 1200MHz 50 40 30 20 10 0 0 0 4 8 12 16 20 24 28 32 0 36 Voltage Variable RF Attenuator 4 8 12 16 20 24 Attenuation (dB) Attenuation (dB) 9 REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz TYPICAL OPERATING CONDITIONS [S2P VS. FREQUENCY] (-5-) Min. & Max. Attenuation vs. Frequency Min. & Max. Attenuation Slope vs. Frequency -8 -2 -16 -40C / 0.0V 25C / 0.0V 105C / 0.0V -40C / 2.8V 25C / 2.8V 105C / 2.8V -4 40 Min/Max ATTN slope (dB/V) Attenuation (dB) 0 -24 -6 -32 -8 0 500 1000 1500 2000 30 25 20 15 max slope 10 min slope 5 0 -40 3000 2500 VCTRL varied from 0.8V to 1.7V 35 0 500 1000 -5 -10 -15 -20 -40C 25C 105C -35 3000 0 -5 -10 -15 -20 -40C -25 25C -30 105C -35 -40 -40 0 500 1000 1500 2000 2500 0 3000 500 1000 1500 2000 2500 3000 Frequency (MHz) Frequency (MHz) Gain Compression vs. Frequency Max. Insertion Phase ∆ vs. Frequency 1 70 (positive phase = electrically shorter) Gain Compression (dB) Max Insertion Phase ∆ (deg) 2500 Worst-Case RF2 Return Loss vs. Frequency 0 RF2 Worstcase Return Loss (dB) RF1 WorstCase Return Loss (dB) Worst-Case RF1 Return Loss vs. Frequency -30 2000 Frequency (MHz) Frequency (MHz) -25 1500 60 50 40 30 -40C 25C 20 105C 10 0 0.5 1MHz 125MHz 250MHz 500MHz 1000MHz 2700MHz 0 -0.5 -1 -1.5 -2 0 500 1000 1500 2000 2500 3000 10 Voltage Variable RF Attenuator 14 18 22 26 30 34 RF Input Power (dBm) Frequency (MHz) 10 REV O, July 2015 38 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz TYPICAL OPERATING CONDITIONS [S2P @ LOW FREQUENCY, GROUP DELAY] (-6-) Low-Frequency Attenuation vs. VCTRL 0 0 -5 -5 -10 -10 Attenuation (dB) Attenuation (dB) Min. & Max. Attenuation vs. Low Frequency 0.0V -15 -20 2.8V -25 -30 1.0MHz 3.0MHz 7.0MHz -15 10.0MHz 50.0MHz -20 100.0MHz -25 -30 -35 -35 -40 -40 -45 -45 0 10 20 30 40 50 60 70 80 90 100 0.0 0.4 0.8 Frequency (MHz) 0 0 -15 2.0 2.4 -20 -25 -30 -35 -10 -15 -20 -25 -30 -35 -40 -40 0.0 0.4 0.8 1.2 1.6 2.0 2.4 2.8 0.0 VCTRL (V) 0.4 0.8 1.2 1.6 2.0 2.4 VCTRL (V) Group Delay vs. Frequency 200 Group Delay (picosec) 2.8 0.5MHz 1.0MHz 3.0MHz 7.0MHz 10.0MHz 50.0MHz 100.0MHz -5 RF2 Return Loss (dB) -10 1.6 Low-Frequency RF2 Return Loss vs. VCTRL 0.5MHz 1.0MHz 3.0MHz 7.0MHz 10.0MHz 50.0MHz 100.0MHz -5 1.2 VCTRL (V) Low-Frequency RF1 Return Loss vs. VCTRL RF1 Return Loss (dB) 0.5MHz 25C -40C / 0.8V -40C / 1.8V 150 25C / 0.8V 25C / 1.8V 100 105C / 0.8V 105C / 1.8V 50 0 -50 -100 0 500 1000 1500 2000 2500 3000 Frequency (MHz) Voltage Variable RF Attenuator 11 REV O, July 2015 2.8 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz TYPICAL OPERATING CONDITIONS 500MHZ, VDD=3.3V [IP3, IP2, IH2, IH3 VS. VCTRL, VMODE] (-7-) Output IP3 vs. VCTRL Input IP3 vs. VCTRL 80 80 70 Output IP3 (dBm) Input IP3 (dBm) 70 60 50 -40C / Vmode = 0V 25C / Vmode = 0V 105C / Vmode = 0V -40C / Vmode = 3V 25C / Vmode = 3V 105C / Vmode = 3V 40 30 60 50 40 30 -40C / Vmode = 0V 25C / Vmode = 0V 105C / Vmode = 0V -40C / Vmode = 3V 25C / Vmode = 3V 105C / Vmode = 3V 20 10 0 20 0 0.4 0.8 1.2 1.6 2 2.4 0 2.8 0.4 0.8 120 110 110 Output IP2 (dBm) Input IP2 (dBm) 120 100 90 80 -40C / Vmode = 3V 25C / Vmode = 3V 105C / Vmode = 3V -40C / Vmode = 0V 25C / Vmode = 0V 105C / Vmode = 0V 70 60 50 0.8 1.2 1.6 2 2.4 70 60 -40C / Vmode = 0V 25C / Vmode = 0V 105C / Vmode = 0V -40C / Vmode = 3V 25C / Vmode = 3V 105C / Vmode = 3V 50 30 0 0.4 0.8 80 120 70 IH3 (dBm) IH2 (dBm) 130 110 100 90 -40C / Vmode = 0V 25C / Vmode = 0V 105C / Vmode = 0V -40C / Vmode = 3V 25C / Vmode = 3V 105C / Vmode = 3V 70 60 50 1.2 1.6 2 2.4 2.8 2 2.4 60 50 -40C / Vmode = 0V 25C / Vmode = 0V 105C / Vmode = 0V -40C / Vmode = 3V 25C / Vmode = 3V 105C / Vmode = 3V 40 30 20 10 0 2.8 0.4 0.8 1.2 1.6 2 2.4 2.8 VCTRL (V) VCTRL (V) Voltage Variable RF Attenuator 1.6 3rd Harm Input Intercept Point vs. VCTRL 90 80 1.2 VCTRL (V) 140 0.8 2.8 80 2.8 2nd Harm Input Intercept Point vs. VCTRL 0.4 2.4 90 VCTRL (V) 0 2 100 40 40 0.4 1.6 Output IP2 vs. VCTRL Input IP2 vs. VCTRL 0 1.2 VCTRL (V) VCTRL (V) 12 REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz TYPICAL OPERATING CONDITIONS 500MHZ, VDD=3.3V [IP3, IP2, IH2, IH3 VS. VCTRL, RF1/RF2 DRIVEN] (-8-) Output IP3 vs. VCTRL 80 70 70 60 Output IP3 (dBm) Input IP3 (dBm) Input IP3 vs. VCTRL 60 50 -40C / RF1 Driven 25C / RF1 Driven 105C / RF1 Driven -40C / RF2 Driven 25C / RF2 Driven 105C / RF2 Driven 40 30 20 0 0.4 0.8 1.2 1.6 2 2.4 -40C / RF1 Driven 25C / RF1 Driven 105C / RF1 Driven -40C / RF2 Driven 25C / RF2 Driven 105C / RF2 Driven 50 40 30 20 10 0 2.8 0.4 0.8 VCTRL (V) 120 110 110 Output IP2 (dBm) Input IP2 (dBm) 120 100 90 80 70 -40C / RF1 Driven 25C / RF1 Driven 105C / RF1 Driven -40C / RF2 Driven 25C / RF2 Driven 105C / RF2 Driven 60 50 40 0.4 0.8 1.2 1.6 2 2.4 100 90 70 60 50 30 0 2.8 0.4 0.8 120 80 110 70 100 90 -40C / RF1 Driven 25C / RF1 Driven 105C / RF1 Driven -40C / RF2 Driven 25C / RF2 Driven 105C / RF2 Driven 70 60 50 1.2 1.6 2 2.4 2.8 2 2.4 60 50 40 -40C / RF1 Driven 25C / RF1 Driven 105C / RF1 Driven -40C / RF2 Driven 25C / RF2 Driven 105C / RF2 Driven 30 20 10 0 2.8 0.4 0.8 1.2 1.6 2 2.4 2.8 VCTRL (V) VCTRL (V) Voltage Variable RF Attenuator 1.6 3rd Harm Input Intercept Point vs. VCTRL 90 80 1.2 VCTRL (V) IH3 (dBm) IH2 (dBm) 2.8 80 130 0.8 2.4 40 2nd Harm Input Intercept Point vs. VCTRL 0.4 2 -40C / RF1 Driven 25C / RF1 Driven 105C / RF1 Driven -40C / RF2 Driven 25C / RF2 Driven 105C / RF2 Driven VCTRL (V) 0 1.6 Output IP2 vs. VCTRL Input IP2 vs. VCTRL 0 1.2 VCTRL (V) 13 REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz TYPICAL OPERATING CONDITIONS 500MHZ, VDD=3.3V [IP3, IP2, IH2, IH3 VS. ATTENUATION] (-9-) Input IP3 vs. Attenuation Output IP3 vs. Attenuation 80 80 70 70 Output IP3 (dBm) Input IP3 (dBm) -40C 60 50 40 -40C 25C 30 25C 105C 60 50 40 30 20 105C 20 10 0 4 8 12 16 20 24 28 32 36 0 4 8 Attenuation (dB) Input IP2 vs. Attenuation 16 20 24 28 32 36 Output IP2 vs. Attenuation 120 120 110 110 25C 100 100 105C Output IP2 (dBm) Input IP2 (dBm) 12 Attenuation (dB) 90 80 70 60 -40C 50 25C -40C 90 80 70 60 50 40 105C 30 40 0 4 8 12 16 20 24 28 32 0 36 4 8 2nd Harm Input Intercept Point vs. Attenuation 16 20 24 28 32 36 3rd Harm Input Intercept Point vs. Attenuation 140 90 130 80 120 70 IH3 (dBm) IH2 (dBm) 12 Attenuation (dB) Attenuation (dB) 110 100 90 60 50 40 80 -40C 30 70 25C 20 -40C 25C 105C 105C 60 10 0 4 8 12 16 20 24 28 32 36 0 Voltage Variable RF Attenuator 4 8 12 16 20 24 28 32 36 Attenuation (dB) Attenuation (dB) 14 REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz TYPICAL OPERATING CONDITIONS 500MHZ, VDD=3.3V [IP3, IP2, IH2, IH3 VS. VCTRL, RF1/RF2 DRIVEN] (-10-) Output IP3 vs. Attenuation 80 70 70 60 Output IP3 (dBm) Input IP3 (dBm) Input IP3 vs. Attenuation 60 50 -40C / RF1 Driven 25C / RF1 Driven 105C / RF1 Driven -40C / RF2 Driven 25C / RF2 Driven 105C / RF2 Driven 40 30 20 0 4 8 12 16 20 24 28 32 -40C / RF1 Driven 25C / RF1 Driven 105C / RF1 Driven -40C / RF2 Driven 25C / RF2 Driven 105C / RF2 Driven 50 40 30 20 10 0 36 4 8 Attenuation (dB) 120 110 110 100 90 80 70 -40C / RF1 Driven 25C / RF1 Driven 105C / RF1 Driven -40C / RF2 Driven 25C / RF2 Driven 105C / RF2 Driven 60 50 40 4 8 12 16 20 24 28 32 100 90 50 30 0 36 4 8 IH3 (dBm) IH2 (dBm) 70 100 90 80 -40C / RF1 Driven 25C / RF1 Driven 105C / RF1 Driven -40C / RF2 Driven 25C / RF2 Driven 105C / RF2 Driven 60 50 20 24 16 20 24 28 32 36 3rd Harm Input Intercept Point vs. Attenuation 110 70 12 Attenuation (dB) 80 28 32 60 50 40 -40C / RF1 Driven 25C / RF1 Driven 105C / RF1 Driven -40C / RF2 Driven 25C / RF2 Driven 105C / RF2 Driven 30 20 10 0 36 4 8 12 16 20 24 28 32 Attenuation (dB) Attenuation(dB) Voltage Variable RF Attenuator 36 60 120 16 32 70 90 12 28 80 130 8 24 40 2nd Harm Input Intercept Point vs. Attenuation 4 20 -40C / RF1 Driven 25C / RF1 Driven 105C / RF1 Driven -40C / RF2 Driven 25C / RF2 Driven 105C / RF2 Driven Attenuation (dB) 0 16 Output IP2 vs. Attenuation 120 Output IP2 (dBm) Input IP2 (dBm) Input IP2 vs. Attenuation 0 12 Attenuation (dB) 15 REV O, July 2015 36 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz PACKAGE DRAWING (3X3 16 PIN) Voltage Variable RF Attenuator 16 REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz GND 15 14 NC VDD 16 VCTRL VMODE PINOUT & BLOCK DIAGRAM 13 1 12 GND Control NC 2 11 NC RF1 3 10 RF2 NC 4 9 NC Voltage Variable RF Attenuator 17 RTN 7 8 RTN 6 GND 5 RTN E.P. REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz PIN DESCRIPTION Pin Name Function 1, 7, 12 GND 2, 4, 9, 11, 13 NC 3 RF1 5, 6, 8 RTN 10 RF2 14 VCTRL 15 VDD 16 VMODE Ground these pins as close to the device as possible. No internal connection. IDT recommends connecting these pins to GND. RF Port 1. Matched to 50 ohms. Must use an external AC coupling capacitor as close to the device as possible. For low frequency operation increase the capacitor value to result in a low reactance at the frequency of interest. Attenuator Ground Return. Each of these pins require a capacitor to GND to provide an RF return path. Placed as close to the device as possible. RF Port 2. Matched to 50 ohms. Must use an external AC coupling capacitor as close to the device as possible. For low frequency operation increase the capacitor value to result in a low reactance at the frequency of interest. Attenuator control voltage. Apply a voltage in the range as specified in the Operating Conditions Table. See application section for details about VCTRL. Power supply input. Bypass to GND with capacitors close as possible to pin. Attenuator slope control. Set to logic LOW to enable negative attenuation slope. Set to logic HIGH to enable positive attenuation slope. Exposed Pad. Internally connected to GND. Solder this exposed pad to a PCB pad that uses multiple ground vias to achieve the specified RF performance. — EP Voltage Variable RF Attenuator 18 REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz APPLICATIONS INFORMATION Default Start-up VMODE must be tied to either GND or Logic High. If the VCTRL pin is left floating, the part will power up in the minimum attenuation state when VMODE = GND, or the maximum attenuation state when VMODE = High. VCTRL The VCTRl pin is used to control the attenuation of the F2255. With VMODE set to a logic low (high), this places the device in a negative (positive) slope mode where increasing (decreasing) the VCTRL voltage produces an increasing (a decreasing) attenuation from min attenuation (max attenuation) to max attenuation (min attenuation) respectively. See the Operating Conditions Table for the allowed control voltage range and its dependence on VDD. The VCTRl pin has an on-chip pullup ESD diode so VDD should be applied before VCTRl is applied. If this sequencing is not possible, then resistor R2 should be set for 1kΩ to limit the current into the VCTRl pin. VMODE The VMODE pin is used to set the attenuation vs. VCTRl slope. With VMODE set to logic low (high) this will set the attenuation slope to be negative (positive). A negative (positive) slope is defined as increasing (decreasing) attenuation with increasing (decreasing) VCTRl voltage. The EVKIT provides an on-board jumper to manually set the VMODE. Install a jumper on header J2 from VMODE (pin2) to GND (pin3) to set the device for a negative slope. For a positive slope install the J2 jumper from VMODE (pin2) to VHI (pin1). For proper operation one of the above noted jumper positions must be selected. RF1 and RF2 Ports The F2255 is a bi-directional device thus allowing RF1 or RF2 to be used as the RF input. As displayed in the Typical Operating Conditions curves, RF1 shows enhanced linearity when used as the RF input. VDD must be applied prior to the application of RF power to ensure reliability. DC blocking capacitors are required on the RF pins and should be set to a value that results in a low reactance over the frequency range of interest. Power Supplies The supply pin should be bypassed with external capacitors to minimize noise and fast transients. Supply noise can degrade noise figure and fast transients can trigger ESD clamps and cause them to fail. Supply voltage change or transients should have a slew rate smaller than 1V/20uS. In addition, all control pins should remain at 0V (+/-0.3V) while the supply voltage ramps or while it returns to zero. Voltage Variable RF Attenuator 19 REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz Control Pin Interface If control signal integrity is a concern and clean signals cannot be guaranteed due to overshoot, undershoot, ringing, etc., the following circuit at the input of control pins 14 and 16 is recommended as shown below. Voltage Variable RF Attenuator 20 REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz EVKIT / APPLICATIONS CIRCUIT Voltage Variable RF Attenuator 21 REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz EVKIT PICTURE / LAYOUT (TOP VIEW) Voltage Variable RF Attenuator 22 REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz EVKIT PICTURE / LAYOUT (BOTTOM VIEW) Voltage Variable RF Attenuator 23 REV O, July 2015 IDTF2255NLGK Datasheet Voltage Variable RF Attenuator 1MHz to 3000MHz EVKIT BOM TOP MARKINGS Voltage Variable RF Attenuator 24 REV O, July 2015