DR65-0002 Linear Driver for PIN Diode Attenuators Features n n n n n n n n V 4.00 SOW-16 Linearizes PIN Diode Attenuators Over a Wide Attenuation Range Output Currents up to 12 mA Operates with a Single Supply Voltage of +3V to +12V Low Quiescent Currents Single Control Voltage SOW-16, Wide Body Plastic Package Test Boards are Available Tape and Reel Packaging Available Description M/A-COM's DR65-0002 is a break point free driver that produces a logarithmic output current suitable for linearizing PIN diode based shunt attenuators. This driver, in conjunction with customer defined external components, produces a linear transfer function (dB/V) between the input control voltage of the driver and the attenuation output of the PIN attenuator. The DR65-0002 has been optimized for linearizing M/A-COM’s AT10-0009 or AT10-0017 attenuators, but will function well with most types of cathode grounded, PIN attenuators. The driver is packaged in a SOW-16 package for commercial SMT applications. A typical schematic for a 30 dB, 7.5 dB/V linear attenuator is shown in Figure 1. Package outline conforms to JEDEC standard MS-013AA Circuit Description: Figure 1 (Reference Figures 1 and 2) The input divider, R1 and the sum of R2 and R3, sets the overall transfer function of the circuit. To increase the transfer function, decrease the Control Voltage and the value of R1. Varying the value of R4 will optimize the linearity of the circuit. One can achieve a very linear transfer function (<± 1 dB/V) by driving the attenuator over a smaller portion of its dynamic range. In the case of the AT10-0009 and AT10-0017 attenuators, this would be limited to a dynamic range of 28 and 25 dB, respectively. Temperature compensation is a function temperature coefficient of the thermistor, R3, and the ratio of R2 to R3, and can only be optimized once the transfer function and linearity component values have been established. RFin +Vcc C1 .01 µF R1 2 1,3,4 16,14,13 14 4 Vcontrol (0 to 4V) IN 39K 12 ATTENNUATOR 7 DR65-0002 R2 680 REF 3 R3 (PTCT) 330 R4 5,6,8 9,11,12 5 360 10 RFoutput NOTES: TRANSFER FUNCTION IS 7.5 dB/V Vcontrol IS 0V to 4.0V +Vcc IS 5.0V ± 5% R3 IS A POSITIVE TEMPERATURE COEFFICIENT THERMISTOR ATTENUATOR IS AT10-0009 OR AT10-0017 SCHEMATIC LINEAR ATTENUATOR Linear Driver for PIN Diode Attenuators DR65-0002 V 4.00 Electrical Specifications, TA = +25°C, Reference Figure 1 Parameter Test Conditions Units Min Typical Max Output Drive Current Load Dependent mA 10 — — +VCC Supply Range — V 3.0 5.0 12 +VCC Supply Tolerance — % — 5 — +VCC Quiescent Current No Load mA — 1.0 2.0 Linearity Application Dependent dB ±1 ± 2.5 — Transfer Function Application Dependent dB/V 3 7.5 10 Settling Time 50% Ctl to 90%/10% RF µS — 50 — Absolute Maximum Ratings 1 Figure 2—Typical Attenuation Error LINEARITY ERROR DR65-0002 Driver with AT10-0017 Attenuator 2 1.5 Attenuation Error 1 0.5 0 0 3 6 9 12 15 18 21 24 27 Parameter Absolute Maximum +VCC +20 V Input + ±5V REF ±5V Output Current 20 mA Operating Temperature -40ºC to +85ºC Storage Temperature -65ºC to +125ºC 30 -0.5 -1 -1.5 Package Power Dissipation 150 mW Lead Temperature 300ºC for 10 seconds -2 Attenuation (dB) Frequency: 1960 MHz Vcont: 0 to 4.0V 1. Operation of this device above any one of these parameters may cause permanent damage. Pin Configuration Ordering Information Pin # Function Pin # Function 1 N/C 9 N/C DR65-0002 Bulk Packaging 2 N/C 10 N/C DR65-0002TR Tape & Reel (1K Reel) 3 REF 11 N/C DR65-0002-TBG 4 INPUT + 12 OUTPUT Test Board with Circuit per Figure 1 (AT10-0009, GSM Attenuator) 5 GND 13 N/C DR65-0002-TBP Test Board with Circuit per Figure 1 (AT10-0017, PCS Attenuator) 6 N/C 14 + VCC 7 N/C 15 N/C 8 N/C 16 N/C Specifications subject to change without notice. n North America: Tel. (800) 366-2266 n Asia/Pacific: Tel.+81-44-844-8296, Fax +81-44-844-8298 n Europe: Tel. +44 (1344) 869 595, Fax+44 (1344) 300 020 Visit www.macom.com for additional data sheets and product information. Part Number Package 2