General Description

The MAX4000/MAX4001/MAX4002 low-cost, low-power

logarithmic amplifiers are designed to control RF power

amplifiers (PA) operating in the 0.1GHz to 2.5GHz fre-

quency range. A typical dynamic range of 45dB makes

this family of log amps useful in a variety of wireless appli-

cations including cellular handset PA control, transmitter

power measurement, and RSSI for terminal devices.

Logarithmic amplifiers provide much wider measurement

range and superior accuracy to controllers based on

diode detectors. Excellent temperature stability is

achieved over the full operating range of -40°C to +85°C.

The choice of three different input voltage ranges elimi-

nates the need for external attenuators, thus simplifying

PA control-loop design. The logarithmic amplifier is a volt-

age-measuring device with a typical signal range of

-58dBV to -13dBV for the MAX4000, -48dBV to -3dBV for

the MAX4001, and -43dBV to +2dBV for the MAX4002.

The input signal for the MAX4000 is internally AC-coupled

using an on-chip 5pF capacitor in series with a 2k

Ω input

resistance. This highpass coupling, with a corner at

16MHz, sets the lowest operating frequency and allows

the input signal source to be DC grounded. The

MAX4001/MAX4002 require an external coupling capaci-

tor in series with the RF input port. These PA controllers

feature a power-on delay when coming out of shutdown,

holding OUT low for approximately 5µs to ensure glitch-

free controller output.

The MAX4000/MAX4001/MAX4002 family is available in

an 8-pin µMAX package and an 8-bump chip-scale pack-

age (UCSP™). The device consumes 5.9mA with a 5.5V

supply, and when powered down the typical shutdown

current is 13µA.

Applications

Transmitter Power Measurement and Control

TSSI for Wireless Terminal Devices

Cellular Handsets (TDMA, CDMA, GPRS, GSM)

RSSI for Fiber Modules

UCSP is a registered trademark of Maxim Integrated Products,

Inc.

Features

o Complete RF-Detecting PA Controllers

o Variety of Input Ranges

MAX4000: -58dBV to -13dBV

(-45dBm to 0dBm in 50

Ω)

MAX4001: -48dBV to -3dBV

(-35dBm to +10dBm in 50

Ω)

MAX4002: -43dBV to +2dBV

(-30dBm to +15dBm in 50

Ω)

o Frequency Range from 100MHz to 2.5GHz

o Temperature Stable Linear-in-dB Response

o Fast Response: 70ns 10dB Step

o 10mA Output Sourcing Capability

o Low Power: 17mW at 3V (typ)

o Shutdown Current 30µA (max)

o Available in an 8-Bump UCSP and a Small 8-Pin

µMAX Package

2.5GHz 45dB RF-Detecting Controllers

________________________________________________________________ Maxim Integrated Products

1

19-2288; Rev 1; 7/02

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.

Ordering Information

PART

TEMP RANGE

PIN-

PACKAGE

TOP

MARK

MAX4000EBL-T

-40

°C to +85°C

8 UCSP-8

ABF

MAX4000EUA

-40

°C to +85°C

8 µMAX

—

MAX4001EBL-T

-40

°C to +85°C

8 UCSP-8

ABE

MAX4001EUA

-40

°C to +85°C

8 µMAX

—

MAX4002EBL-T

-40

°C to +85°C

8 UCSP-8

ABD

MAX4002EUA

-40

°C to +85°C

8 µMAX

—

Functional Diagram

10dB

DET

10dB

10dB

10dB

DET

DET

DET

DET

OFFSET

COMP

LOW-

NOISE

BANDGAP

OUTPUT

ENABLE

DELAY

GND

(PADDLE)

gm

+

-

X1

V-I

RFIN

SHDN

OUT

CLPF

SET

MAX4000

Pin Configurations appear at end of data sheet.