Rainbow Electronics MAX11008 - Manual

General Description
The MAX11008 controller biases RF LDMOS power
devices found in cellular base stations and other wire-
less infrastructure equipment. Each controller includes
a high-side current-sense amplifier with programmable
gains of 2, 10, and 25 to monitor the LDMOS drain cur-
rent over a range of 20mA to 5A. The MAX11008 sup-
ports up to two external diode-connected transistors to
monitor the LDMOS temperatures while an internal tem-
perature sensor measures the local die temperature. A
12-bit successive-approximation register (SAR) analog-
to-digital converter (ADC) converts the analog signals
from the programmable-gain amplifiers (PGAs), exter-
nal temperature sensors, internal temperature measure-
ment, and two additional auxiliary inputs. The
MAX11008 automatically adjusts the LDMOS bias volt-
ages by applying temperature, AIN, and/or drain cur-
rent samples to data stored in lookup tables (LUTs).
The MAX11008 includes two gate-drive channels, each
consisting of a 12-bit DAC to generate the positive gate
voltage for biasing the LDMOS devices. Each gate-
drive output supplies up to ±2mA of gate current. The
gate-drive amplifier is current-limited to ±25mA and
features a fast clamp to AGND.
The MAX11008 contains 4Kb of on-chip, nonvolatile
EEPROM organized as 256 bits x 16 bits to store LUTs
and register information. The device operates from
either a 4-wire 16MHz SPI™-/MICROWIRE™-compati-
ble or an I
2 C-compatible serial interface.
The MAX11008 operates from a +4.75V to +5.25V ana-
log supply with a typical supply current of 2mA, and a
+2.7V to +5.25V digital supply with a typical supply of
3mA. The device is packaged in a 48-pin, 7mm x 7mm,
thin QFN package and operates over the extended
(-40°C to +85°C) temperature range.
Applications
Cellular Base Stations
Microwave Radio Links
Feed-Forward Power Amps
Transmitters
Industrial Process Control
Features
♦ On-Chip 4Kb EEPROM for Storing LDMOS Bias
Characteristics
♦ Integrated High-Side Current-Sense PGA with
Gain of 2, 10, or 25
♦ ±0.75% Accuracy for Sense Voltage Between
+75mV and +1250mV
♦ Full-Scale Sense Voltage
+100mV with a Gain of 25
+250mV with a Gain of 10
+1250mV with a Gain of 2
♦ Common-Mode Range, LDMOS Drain Voltage:
+5V to +32V
♦ Adjustable Low-Noise 0 to AV
DD Output Gate
Bias Voltage Range
♦ Fast Clamp to AGND for LDMOS Protection
♦ 12-Bit DAC Control of Gate with Temperature
♦ Internal Die Temperature Measurement
♦ 2-Channel External Temperature Measurement
through Remote Diodes
♦ Internal 12-Bit ADC Measurement for
Temperature, Current, and Voltage Monitoring
♦ User-Selectable Serial Interface
400kHz/1.7MHz/3.4MHz I 2 C-Compatible Interface
16MHz SPI-/MICROWIRE-Compatible Interface
MAX11008
Dual RF LDMOS Bias Controller with
Nonvolatile Memory
________________________________________________________________ Maxim Integrated Products 1
19-4371; Rev 0; 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.
EVALUATION KIT
AVAILABLE
SPI is a trademark of Motorola, Inc.
MICROWIRE is a trademark of National Semiconductor Corp.
Ordering Information
PART PIN-PACKAGE
TEMP
ERROR (°C)
MAX11008BETM+ 48 TQFN-EP* ±3
+ Denotes a lead-free/RoHS-compliant package.
* EP = Exposed pad.
Note: The device is specified over the -40°C to +85°C operating
temperature range.