AD7011

Features:

Single +5 V Supply
On-Chip p/4 DQPSK Modulator
Modulator Bypass Analog Mode
Root-Raised Cosine Tx Filters, a = 0.35
Two 10-Bit D/A Converters
4th Order Reconstruction Filters
Differential Analog Outputs
On-Chip Ramp Up/Down Power Control
On-Chip Tx Offset Calibration
Dual Mode Operation, Analog and Digital
Very Low Power Dissipation, 30 mW typical
Power Down Mode < 10 mA
On-Chip Voltage Reference
24-Pin SSOP


Application

American Digital Cellular Telephony
American Analog Cellular Telephony


Pinout




Specifications

V_DD Tx, V_DD Rx to AGND  . . . . . . . . . . . . . . .0.3 V to +7 V
AGND to DGND  . . . . . . . . . . . . . . . . . . . .  0.3 V to +0.3 V
Digital I/O Voltage to DGND  . . . . . . .0.3 V to V_DD + 0.3 V
Analog I/O Voltage to AGND  . . . . . . 0.3 V to V_DD + 0.3 V
Operating Temperature Range
Industrial (A Version)  . . . . . . . . . . . . . . .  40°C to +85°C
Storage Temperature Range  . . . . . . . . .65°C to + 150°C
Junction Temperature  . . . . . . . . . . . . . . . . . . . . . . +150°C
SSOP _JA Thermal Impedance  . . . . . . . . . . . . . .+122°C/W
Lead Temperature, Soldering
Vapor Phase (60 sec)  . . . . . . . . . . . . . . . . . . . . .  +215°C
Infrared (15 sec)  . . . . . . . . . . . . . . . . . . . . . . . . .  +220°C


Description

The AD7011 is a complete low power, CMOS, /4 DQPSK modulator with single +5 V power supply. The part is designed to perform the baseband conversion of I and Q transmit waveforms in accordance with the American Digital Cellular Tele- phone system (TIA IS-54). The on-chip /4 Differential Quadrature Phase Shift Keying (DQPSK) digital modulator, which includes the root raised cosine filters, generates I and Q data in response to the transmit data stream. The AD7011 also contains ramp control envelope logic to shape the I and Q output waveforms when ramping up or down at the beginning or end of a transmit burst.

Besides providing all the necessary logic to perform /4 DQPSK modulation, the part also provides reconstruction filters to smooth the DAC outputs, providing continuous time analog outputs. The AD7011 generates differential analog outputs for both the I and Q signals. As it is a necessity for all digital mobile systems to use the lowest possible power, the device has transmit and receive power-down options. The AD7011 is housed in a space efficient 24 pin
SSOP (Shrink Small Outline Package).