XR76108 Datasheet, PDF (4/17 Pages) Exar Corporation – 8A and 12A Synchronous Step Down COT Regulator

XR76108 and XR76112
Parameter
Min.
XR76108 Output Power Stage
High-side MOSFET RDSON
Low-side MOSFET RDSON
Maximum Output Current
8
XR76112 Output Power Stage
High-side MOSFET RDSON
Low-side MOSFET RDSON
Maximum Output Current
12
Typ.
21
7
11
5
Max. Units
28 mΩ
10 mΩ
A
15.5 mΩ
9
mΩ
A
VGS=4.5V, IDS=2A
VGS=4.5V, IDS=2A
•
VGS=4.5V, IDS=2A
VGS=4.5V, IDS=2A
•
Conditions
Block Diagram
VCC
TON
VIN
PGOOD
SS
FB
EN/MODE
Enable LDO
LD O
VCC UVLO
4.25 V
+
-
VCC
TJ
150 C
OT P
+
-
10uA
+
-
Switching
Enabled
ES R
emulation &
DC correction
VIN
On-Time
Switching
Enabled
0.6 V
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
VCC
VCC
BST PVIN
GH
SW
GL
AGND
ILIM
Figure 3: XR76108/12 Block Diagram
PGND
© 2013-2014 Exar Corporation
4/17
www.exar.com
Rev. 2A