M A COM MAMDCC0005-DC000, MAMDCC0002-DC000, MADRCC0002TR, MADRCC0002, SA90-0001-DC000 Datasheet

Dual Linear Driver for Vector Modulators
V 2.00
MADRCC0002
Features
n Linearizes M/A-COM’s PIN Diode Vector Modulators
Over a 360° Phase Range
Description
M/A-COM's MADRCC0002 is a dual, break point free driver that produces a logarithmic output current suitable for linearizing PIN diode based vector modulators. This driver, in conjunction with the external components, as defined in Figure 1, produces a linearized transfer function between the input control voltage of the driver and the attenuation / phase output of the vector modulator. The MADRCC0002 has been optimized for linearizing M/A-COM’s Vector Modulators (see Table 1), but will function well with most types of cathode grounded vector modulators. The driver is packaged in a 6 x 4 mm Chip Scale Package for commercial SMT applications. A typical schematic for a dual linearizer driving a vector modulator is shown in Figure 1.
CSP-9
Circuit Description:
(Reference Figures 1, 2 and 3)
Note that this is a dual driver. Only the top circuit will be described, because the bottom circuit is identical. 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. Temperature compensation is a function of the 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. Varying the value of R4 will optimize the linearity of the VVA. One can achieve a more linear transfer function by driving the attenuator over a smaller portion of its dynamic range. Note that when the vector modulators called out in Table 1 are driven with the dual linearizer, both amplitude and phase are affected, which makes it hard to define linearity. The individual transfer function of each voltage variable attenuator in the vector modulator (See Figure 2 for the block diagram) is linearized as a function of voltage. The two VVAs in the block diagram are the quad hybrids that are terminated by two PIN diodes. See Figure 3 for the transfer function of the SA90-0001 vector modulator (phase and attenuation vs. control voltages).
Absolute Maximum Ratings 1
Parameter Absolute Maximum
+V
CC
IN A, IN B -0.5V < Input < Vcc +0.5V
REF A, REF B -0.5V < Input < Vcc +0.5V
Output Short Circuit Current 20 mA
Operating Temperature -40°C to +85°C
Storage Temperature -65°C to +125°C
Package Power Dissipation
Control Voltage
Lead Temperature 300ºC for 10 seconds
1. Operation of this device above any one of these parameters may cause permanent damage.
+20 V
150 mW
Dual Linear Driver for Vector Modulators
Electrical Specifications, TA = +25°C, Reference Figure 1 (Each Circuit)
Parameter Test Conditions Units Min Typical Max
Output Drive Current Vcontrol = VCC mA 18
+VCC Supply Range V 4.5 5.0 5.5
IN, REF Voltage V 0 VCC
+VCC Quiescent Current No Load µA 50 70
Settling Time 50% Ctl to 90%/10% RF µS 25
MADRCC0002
V 2.00
Figure 1
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.
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