CS5308 datasheet(25/31 Pages) ONSEMI

25 / 31 page

CS5308

http://onsemi.com

saturating, the differential input voltage from CSREF to CSn

(n = 1 or 2) must satisfy the following equation:

VCSREF,MAX ) VCOn,MAX ) 310 mV @ D v 2.45 V

(35)

where:

VCSREF,MAX + Max VID Setting w AVP @ Full Load

VCOn,MAX + [VCSn * VCSREF] @ GCSA,MAX

+ (IO,MAX 2 ) DILo 2) @ RMAX

@ GCSA,MAX

RMAX + RSENSE or (RL,MAX ) RPCB,MAX)

11. VTTPGD Delay Time Setting

The VTTPGD signal is pulled LOW a predetermined delay

time (TD,VTT) after the VTT voltage crosses the VTT

Threshold. The VTTCT charge current and the capacitor

value from the VTTCT pin to ground (CVTT) determine the

TD,VTT delay time. However, the choice of oscillator

frequency and the value of ROSC set the VTTCT charge

current as shown in Figure 4. Therefore, delay time is simply

set by the value of CVTT according to the following

equation:

TD,VTT + (1 V * 0.25V) @ CVTT VTTCT_Current (36)

12. Soft Start Time

The Soft Start time (TSS) can be calculated from:

TSS + (VCOMP * RCMP1 @ ICOMP) @ CCMP2 ICOMP

(37)

where:

VCOMP + VOUT @0 A ) Channel_Startup_Offset

) Int_Ramp ) GCSA @ Ext_Ramp 2

ICOMP is the COMP source current from the data sheet.

CS5308 데이터시트(PDF) 25 Page - ON Semiconductor