Rainbow Electronics DS1870 User Manual
Ds1870 ldmos rf power-amplifier bias controller, General description, Applications
General Description
The DS1870 is a dual-channel bias controller targeted
toward class AB LDMOS RF power-amplifier applica-
tions. It uses lookup tables (LUTs) to control 256-posi-
tion potentiometers based on the amplifier’s
temperature and drain voltage or current (or other
external monitored signal). With its internal temperature
sensor and multichannel A/D converter (ADC), the
DS1870 provides a cost-effective solution that improves
the amplifier’s efficiency by using nonlinear compensa-
tion schemes that are not possible with conventional
biasing solutions.
Applications
Cellular Base Stations
Medical Equipment
Industrial Controls
Optical Transceivers
Features
♦ Two-Channel Solution for Programmable RF Bias
Control
♦ The Potentiometer’s Position is Automatically
Updated to Compensate for the Ambient
Temperature and the Drain Voltage or Current
♦ A Five-Channel, 13-Bit ADC Continuously
Monitors the Ambient Temperature, V
CC
, V
D
, I
D1,
and I
D2
♦ Hi/Lo Alarms for Each ADC Channel can Trigger a
Fault Output
♦ Nonvolatile Memory for the Device Settings,
Lookup Tables, and 32-Bytes of User Memory
♦ I
2
C™-Compatible Serial Interface with Up to Eight
Devices on the Same Serial Bus
♦ Single 5V Power Supply
♦ Small 16-Pin TSSOP Package
♦ -40°C to +95°C Operational Temperature Range
DS1870
LDMOS RF Power-Amplifier Bias
Controller
______________________________________________ Maxim Integrated Products
1
TSSOP (173 mil)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
L
1
TOP VIEW
W
1
W
2
L
2
I
D1
I
D2
V
D
GND
FAULT
A
0
A
1
A
2
SCL
SDA
H
COM
V
CC
DS1870
Pin Configuration
Ordering Information
Rev 1; 5/04
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.
PART
TEMP RANGE
PIN-PACKAGE
DS1870E-010
-40°C to +95°C
16 TSSOP
(173 mil)
Typical Operating Circuit appears at end of data sheet.
I
2
C is a trademark of Philips Corp. Purchase of I
2
C compo-
nents of Maxim Integrated Products, Inc., or one of its subli-
censed Associated Companies, conveys a license under the
Philips I
2
C Patent Rights to use these components in an I
2
C
system, provided that the system conforms to the I
2
C Standard
Specification as defined by Philips.