NB650/NB650H – 6A, 28V, FAST-TRANSIENT, SYNCHRONOUS STEP-DOWN CONVERTERS
FUNCTIONAL BLOCK DIAGRAM
IN
FREQ
+
-
RSEN
BSTREG
Current Sense
Amplifer
VCC
5V LDO
Over-Current
Timer
OC
EN
REFERENCE
+
-
ILIM
HS Ilimit
Comparator
Refresh
Timer
OFF
Timer
xS Q
xR
PWM
BST
HS_MOS
1M E G
0.4V
0.8V
0.6V
HS
Driver
0
LOGIC
SW
VCC
SS
SOFT
START/STOP
+
+
-
START
Loop
Comparator
Current
Modulator
+
+
-
UV Detect
Comparator
+
MUX1
1
2
0
FB
PGOOD
ON
Timer
LS_MOS
LS
Driver
UV
GND
AGND
0
PGOOD
Comparator
0
DRAIN1
VID1
DRAIN2
VID2
NB650/NB650H Rev. 1.12
www.MonolithicPower.com
10/11/2012
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2012 MPS. All Rights Reserved.
-
OV
OV Detect
Comparator
-
MUX2
1
2
0
VIDSL
Figure 1: Functional Block Diagram
8