Rainbow Electronics MAX746 - Manual (Page 10)

MAX746
High-Efficiency, PWM, Step-Down,
N-Channel DC-DC Controller
10 ______________________________________________________________________________________
LBI
REF
OUT
CC
FB
AV+
CS
SS
LBO
LOW-BATTERY
COMPARATOR
ERROR
AMPLIFIER
EXT
CONTROL
100mV
SHDN
100kHz
OSCILLATOR
+2V
REFERENCE
SLOPE-
COMPENSATION
RAMP
AGND
50mV
GND
PWM
COMPARATOR
LIGHT-LOAD
COMPARATOR
DUAL-MODE
COMPARATOR
V RAMP
SOFT-START
CIRCUITRY
CURRENT-SENSE
AMPLIFIER
CURRENT-LIMIT
COMPARATOR
EXT
CHARGE-PUMP CONTROL
COMPARATOR
UNDERVOLTAGE-
LOCKOUT
COMPARATOR
T T FLIP-
FLOP
4.3V
5V
HIGH
FROM AV+
V+ PUMP
Σ
N
Q
Figure 2. Block Diagram