XR79115 Datasheet, PDF (7/19 Pages) Exar Corporation – 22V, 15A Synchronous Step Down COT Power Module

Functional Block Diagram
XR79115
VCC
TON
VIN
PGOOD
SS
Enable LDO
LDO
VCC UVLO
4.25 V
+
-
VCC
OTP
TJ
+
150 C
-
10uA
+
-
Switching
Enabled
FB 0.6V
ESR
emulation &
DC correction
VIN
On-Time
Switching
Enabled
0.6 V
FB
EN/
MODE
PGOOD comparator
+
0.555 V
-
Short-circuit detection
0.36 V
+
-
1.9 V
Enable LDO
Enable LDO
+
-
CCM or CCM/DCM
+
3V
-
Zero Cross Detect
SW
+
-2 mV
-
Feedback
comparator
+
-
Switching
Enabled
RQ
SQ
RQ
SQ
TON
Minimum
On Time
Dead
Time
Control
Enable
Hiccup
Hiccup
Mode
If 8 consecutive ZCD
Then DCM
If 1 non-ZCD
Then exit DCM
If four
consecutive OCP
OCP
comparator _{+ -}
50uA
BST
PVIN
C_IN
VCC
1uF
PGND
CBST
0.1uF
GH
VCC
GL
SW
L
VOUT
COUT
2.2uF
PGND
GL
AGND
ILIM
PGND
GL
© 2014 Exar Corporation
7 / 19
exar.com/XR79115
Rev 1B