UR5595-S08-R datasheet(9/12 Pages) UTC

9 / 12 page

UR5595

MOS IC

UNISONICTECHNOLOGIESCO.,LTD

9 of 12

www.unisonic.com.tw

QW-R502-062,A

TYPICAL APPLICATION CIRCUITS(Cont.)

FOR DDR-II APPLICATIONS

As a result of the separate VDDQ pin and an internal resistor divider, UR5595 can be utilized in DDR-II system,

figure 5 and 6 show two recommended circuits in DDR-II SDRAM application. The output stage is connected to the

1.8V rail and the AVIN pin can be connected to either a 3.3V or 5V rail. If it is not desirable to use the 1.8V rail it is

possible to connect the output stage to a 3.3V rail. The power dissipation increasing concern must be careful as well

SSTL-II application. The advantage of configuration of figure 6 is that it has the ability to source and sink a higher

maximum continuous current.

VTT

VDDQ

VSENSE

VREF

GND

AVIN

PVIN

CIN

VDDQ=1.8V

AVIN=2.2V ～ 5.5V

COUT

CREF

VREF=0.9V

VTT=0.9V

UTC UR5595

PVIN=1.8V

Figure 5. Recommended DDR-II Termination

Figure 6. DDR-II Termination with higher voltage rails

UR5595-S08-R 数据表(PDF) 9 Page - Unisonic Technologies