Datasheet

0.47 éF
10 éH
Co
C
IN
Cvcc
C
BST
FB
EN
SS
Vin
Linear reg
RON
Timer
Css
R
ON
R
FBT
R
FBB
C
FF
Regulator IC
V
O
Internal
Passives
VOUT
GND
VIN
1
2
3
4
5
6
7
R
ENT
R
ENB
LMZ14203H
SNVS692D –JANUARY 2011–REVISED OCTOBER 2013 www.ti.com
APPLICATION BLOCK DIAGRAM
Figure 52. Application Block Diagram
COT Control Circuit Overview
Constant On Time control is based on a comparator and an on-time one shot, with the output voltage feedback
compared to an internal 0.8V reference. If the feedback voltage is below the reference, the high-side MOSFET is
turned on for a fixed on-time determined by a programming resistor R
ON
. R
ON
is connected to V
IN
such that on-
time is reduced with increasing input supply voltage. Following this on-time, the high-side MOSFET remains off
for a minimum of 260 ns. If the voltage on the feedback pin falls below the reference level again the on-time
cycle is repeated. Regulation is achieved in this manner.
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