U2893B Datasheet, PDF (1/14 Pages) TEMIC Semiconductors – Modulation PLL for GSM, DCS and PCS Systems

U2893B
Modulation PLL for GSM, DCS and PCS Systems
Description
The U2893B is a monolithic integrated circuit. It is
realized using TEMIC’s advanced silicon bipolar UHF5S
technology. The device integrates a mixer, an I/Q modu-
lator, a phase-frequency detector (PFD) with two
synchronous-programmable dividers, and a charge pump.
The U2893B is designed for cellular phones such as GSM,
DCS1800, and PCS1900, applying a transmitter-archi-
tecture where the VCO is operated at the TX output
frequency.
U2893B exhibits low power consumption, and the power-
down function extends battery life.
The IC is available in a shrinked small-outline 28–pin
package (SSO28).
Features
D Supply voltage down to 2.7 V
D Current consumption 40 mA
D Power-down function
D Low-current standby mode
D High-speed PFD and charge pump
D Integrated dividers
Benefits
D High-level RF integration
D TX architecture saves filter costs
D Low external part count
D Small SSO28 package
D One device for various applications
Block Diagram
MDLO
I NI
Q NQ
PUMIX
PU MIXO MIXLO
Voltage
RF
MDO
NMDO
90
grd
+
I/Q modulator
reference
Mixer
NRF
ND
N:1
MUX
VSP
NND
divider
PFD
CPO
RD
R:1
NRD
divider
VS1
VS2
MC
Mode
control
VS3
GND
CPC GNDP
12494
Figure 1. Block diagram
TELEFUNKEN Semiconductors
1 (14)
Rev. A1, 29-Jan-97
Preliminary Information