19-3985; Rev 0; 2/06
Automatic RF MESFET Amplifier
Drain-Current Controllers
General Description
Features
♦ Dual Drain-Current-Sense Gain Amplifier
The MAX11014/MAX11015 set and control bias condi-
tions for dual MESFET power devices found in point-to-
point communication and other microwave base
stations. The MAX11014 integrates complete dual ana-
log closed-loop drain-current controllers for Class A
MESFET amplifier operation, while the MAX11015 tar-
gets Class AB operation. Both devices integrate SRAM
lookup tables (LUTs) that can be used to store temper-
ature and drain-current compensation data.
Preset Gain of 4
±±0.5 Aꢀꢀuraꢀc for Sense ꢁoltaꢂes ꢃetꢄeen
7.mꢁ and 62.mꢁ (MAX11±14)
♦ Common-Mode Sense-Resistor ꢁoltaꢂe Ranꢂe
±0.ꢁ to 11ꢁ (MAX11±14)
.ꢁ to 32ꢁ (MAX11±1.)
♦ Loꢄ-Noise Output GATE ꢃias ꢄith ±1±mA GATE
Each device includes dual high-side current-sense
amplifiers to monitor the MESFET drain currents through
the voltage drop across the sense resistors in the 0 to
625mV range. External diode-connected transistors mon-
itor the MESFET temperatures while an internal tempera-
ture sensor measures the local die temperature of the
MAX11014/MAX11015. The internal DAC sets the volt-
ages across the current-sense resistors by controlling
the GATE voltages. The internal 12-bit SAR ADC digitizes
internal and external temperature, internal DAC voltages,
current-sense amplifier voltages, and external GATE volt-
ages. Two of the 11 ADC channels are available as gen-
eral-purpose analog inputs for analog system monitoring.
Drive
♦ Fast Clamp and Poꢄer-On Reset
♦ 12-ꢃit DAC Controls MESFET GATE ꢁoltaꢂe
♦ Internal Temperature Sensor/Dual Remote Diode
Temperature Sensors
♦ Internal 12-ꢃit ADC Measures Temperature and
ꢁoltaꢂe
♦ Pin-Seleꢀtable Serial Interfaꢀe
304MHz I2C-Compatible Interfaꢀe
2±MHz SPI-/MICROWIRE-Compatible Interfaꢀe
The MAX11014’s gate-drive amplifier functions as an
integrator for the Class A drain-current control loop
while the MAX11015’s gate-drive amplifier functions
with a gain of -2 for Class AB applications. The current-
limited gate-drive amplifier can be fast clamped to an
external voltage independent of the digital input from
the serial interface. Both the MAX11014 and the
MAX11015 include self-calibration modes to minimize
error over time, temperature, and supply voltage.
Ordering Information
PKG
PART
PIN-PACKAGE
AMPLIFIER
CODE
MAX11±14BGTM+ 48 Thin QFN-EP** T4877-6
Class A
MAX11±1.BGTM+* 48 Thin QFN-EP** T4877-6 Class AB
+ Denotes a lead-free package.
*Future product—contact factory for availability.
**EP = Exposed pad.
Note: All devices are specified over the -40°C to +105°C operating
temperature range.
The MAX11014/MAX11015 feature an internal reference
and can operate from separate ADC and DAC external
references. The internal reference provides a well-regu-
lated, low-noise +2.5V reference for the ADC, DAC, and
temperature sensors. These integrated circuits operate
from a 4-wire 20MHz SPI™-/MICROWIRE™-compatible
Pin Configuration and Typical Operating Circuit appear at end
of data sheet.
2
or 3.4MHz I C*-compatible serial interface (pin-selec-
table). Both devices operate from a +4.75V to +5.25V
analog supply (2.8mA typical supply current), a +2.7V
to +5.25V digital supply (1.5mA typical supply current),
and a -4.5V to -5.5V negative supply (1.1mA supply
current). The MAX11014/MAX11015 are available in a
48-pin thin QFN package specified over the -40°C to
+105°C temperature range.
Applications
Cellular Base-Station RF MESFET Bias Controllers
Point-to-Point or Point-to-Multipoint Links
Industrial Process Control
2
*Purchase of I C components from Maxim Integrated Products,
Inc. or one of its sublicensed Associated Companies, conveys
2
a license under the Phillips I C Patent Rights to use these com-
SPI is a trademark of Motorola, Inc.
2
ponents in an I C system, provided that the system conforms to
the I C Standard Specification as defined by Phillips.
MICROWIRE is a trademark of National Semiconductor Corp.
2
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.