Manual

MAX1802
Digital Camera Step-Down
Power Supply
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PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
AUXILIARY DC-DC CONTROLLERS 1, 2, 3 (V
ON1
= V
CON
_ = 3V)
INTERNAL CLOCK
OSC Clock Low Trip Level OSC falling edge 0.2 0.25 0.3 V
V
DCON
_ = 0.625V 0.575 0.625 0.675
OSC Clock High Trip Level
V
DCON
_ = 1.25V to V
VL
1.00 1.05 1.10
V
Maximum Duty Cycle
Adjustment Range
40 90
%
Maximum Duty Cycle V
DCON
_ = 0.625V 43 %
Default Maximum Duty Cycle V
DCON
_ = 1.25V to V
VL
76 %
DCON_ Input Leakage Current V
DCON
_ = 0V to 3V 0.01 1 µA
DCON_ Input Sleep-Mode
Threshold
V
DCON
_ rising, 50mV hysteresis 0.35 0.4 0.45 V
AUXILIARY ERROR AMPLIFIER
FB_ Regulation Voltage Unity gain configuration, FB_ = COMP_ 1.233 1.248 1.263 V
FB_ to COMP_
Transconductance
G
EA
Unity gain configuration, FB_ = COMP_,
-5µA < ILOAD < 5µA
70 100 160 µs
FB_ Input Leakage Current V
FB
_ = 1.35V 5 100 nA
AUXILIARY DRIVERS (DL1, DL2, DL3)
DL_ Driver Resistance Output high or low 4 11 Ω
DL_ Drive Current Sourcing or sinking, V
DL
_ = V
VDDC
/ 2 400 mA
AUXILIARY SOFT-START
Soft-Start Interval 1024
OSC
cycles
AUXILIARY SHORT-CIRCUIT PROTECTION
Fault Interval 1024
OSC
cycles
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, V
VDDM
= 6V, V
VDDC
= 3V, PGNDM = PGND = GND, DCON1 = REF, V
ONM
= 3V, V
ONC
= V
ON1
= V
DCON2
=
V
DCON3
= 0, T
A
= 0°C to +85°C, unless otherwise noted. Typical values are at T
A
= +25°C.)