TPS53114_15 Datasheet, PDF (14/30 Pages) Texas Instruments – TPS53114 Single Synchronous Step-down Controller for Low Voltage Power Rails

TPS53114
SLVS887C – APRIL 2009 – REVISED AUGUST 2014
( ) ^VO1
R1 = ¾ _{¾ R2 0.765 +}
VFB1_(ripple)
2
-1
·
( ) ^VO1
R1 = ¾ _{¾ R2 0.758 +}
VFB1_(ripple)
2
-1
·
Where:
VFB1_(ripple) = Ripple voltage at VFB1
(FSEL = GND)
(FSEL = V5FILT)
9.2.2.7 Choose Over Current Set Point Resistor
( ) _VTRIP
=
æ
ççè I_OCL
-
2
V_IN - V_O
· L1 · ¦_sw
·
V_O
V_IN
ö
÷÷ø
· R_DS(ON)
R_TRIP (kW) =
V_TRIP (mV) - V_OCLoff
I_TRIP (mA)
Where:
R_DS(ON) = Low side FET on-resistance
I_TRIP = TRIP pin source current （≉ 10 μA）
V_OCLoff = Minimum over current limit offset voltage (-20 mV)
I_OCL = over current limit
9.2.2.8 Choose Soft Start Capacitor
Soft start timing equations are as follows:
T
SS
=
C_{¾ 7 2}·_e0_-6.765
(s)
(FSEL = GND)
T
SS
=
C_{¾ 7 2}·_e0_-6.758
(s)
(FSEL = V5FILT)
9.2.2.9 Choose Package Option
TPS53114 power dissipation:
P_d = f_SW · (CiH + CiL) · VREG5 · V_in(max)
Where:
C_iH = Input capacitor of high side MOSFET
C_iL = Input capacitor of low side MOSFET
Choose package considering the Dissipation Rating table.
www.ti.com
(11)
(12)
(13)
(14)
(15)
(16)
(17)
14
Submit Documentation Feedback
Product Folder Links: TPS53114
Copyright © 2009–2014, Texas Instruments Incorporated