Datasheet

General Description
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.
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.
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.
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
or 3.4MHz I
2
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.
Features
♦ Dual Drain-Current-Sense Gain Amplifier
Preset Gain of 4
±0.5% Accuracy for Sense Voltages Between
75mV and 625mV (MAX11014)
♦ Common-Mode Sense-Resistor Voltage Range
0.5V to 11V (MAX11014)
5V to 32V (MAX11015)
♦ Low-Noise Output GATE Bias with ±10mA GATE
Drive
♦ Fast Clamp and Power-On Reset
♦ 12-Bit DAC Controls MESFET GATE Voltage
♦ Internal Temperature Sensor/Dual Remote Diode
Temperature Sensors
♦ Internal 12-Bit ADC Measures Temperature and
Voltage
♦ Pin-Selectable Serial Interface
3.4MHz I
2
C-Compatible Interface
20MHz SPI-/MICROWIRE-Compatible Interface
MAX11014/MAX11015
Automatic RF MESFET Amplifier
Drain-Current Controllers
________________________________________________________________ Maxim Integrated Products 1
PART PIN-PACKAGE AMPLIFIER
MAX11014BGTM+
48 Thin QFN-EP**
Class A
MAX11015BGTM+*
48 Thin QFN-EP**
Class AB
Ordering Information
Applications
19-3985; Rev 3; 11/08
For pricing delivery, and ordering information please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
SPI is a trademark of Motorola, Inc.
MICROWIRE is a trademark of National Semiconductor Corp.
EVALUATION KIT
AVAILABLE
+ 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.
Pin Configuration and Typical Operating Circuit appear at end
of data sheet.
Cellular Base-Station RF MESFET Bias Controllers
Point-to-Point or Point-to-Multipoint Links
Industrial Process Control