Datasheet

MAX1776
24V, 600mA Internal Switch, 100% Duty Cycle,
Step-Down Converter
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ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, V
IN
= +12V, SHDN = IN, T
A
= 0°C to +85°C, unless otherwise noted.)
ELECTRICAL CHARACTERISTICS
(Circuit of Figure 1, V
IN
= +12V, SHDN = IN, T
A
= -40°C to +85°C, unless otherwise noted.) (Note 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Dropout Voltage V
DROPOUT
I
OUT
= 525mA, ILIM = ILIM2 = IN 0.2 V
Line Regulation V
IN
= 8V/24V, 200Ω load 0.1 %/V
Load Regulation No load/full load 0.9 %
Low 0.8
Digital Input Level SHDN, ILIM2
High 2.4
V
Digital Input Leakage Current V
SHDN
, V
ILIM
, V
ILIM2
= 0 or 24V, V
IN
= 24V -1 +1 µA
Low 0.05
ILIM Input Level
High 2.2
V
Thermal Shutdown 10°C hysteresis 160 °C
PARAMETER SYMBOL CONDITIONS MIN MAX UNITS
Input Voltage Range V
IN
4.5 24 V
Input Supply Current I
IN
No load 28 µA
Input Supply Current in Dropout I
IN
(
DROP
)
No load 70 µA
Input Shutdown Current SHDN = GND 7 µA
V
IN
rising 3.6 4.4
Input Undervoltage Lockout
Threshold
V
UVLO
V
IN
falling 3.5 4.3
V
Output Voltage (Preset Mode) V
OUT
FB = GND 4.75 5.25 V
Feedback Set Voltage
(Adjustable Mode)
V
FB
1.2 1.3 V
OUT Bias Current V
OUT
= 5.5V 1.65 6.25 µA
OUT Pin Maximum Voltage 5.5 V
FB Bias Current I
FB
V
FB
= 1.3V -25 +25 nA
FB Dual Mode Threshold Low 45 155 mV
LX Switch Minimum Off-Time t
OFF
(
MIN
)
0.22 0.64 µs
LX Switch Maximum On-Time t
ON
(
MAX
)
V
FB
= 1.3V 7.5 12.5 µs
ILIM = ILIM2 = GND 3.2
ILIM = GND, ILIM2 = IN 1.6
ILIM = IN, ILIM2 = GND 0.8
V
IN
= 6V
ILIM = ILIM2 = IN 0.8
ILIM = ILIM2 = GND 3.8
ILIM = GND, ILIM2 = IN 1.9
ILIM = IN, ILIM2 = GND 0.95
LX Switch On-Resistance R
LX
V
IN
= 4.5V
ILIM = ILIM2 = IN 0.95
Ω
ILIM = ILIM2 = GND 100 200
ILIM = GND, ILIM2 = IN 200 400
ILIM = IN, ILIM2 = GND 400 800
LX Current Limit I
LX
(
PEAK
)
ILIM = ILIM2 = IN 800 1600
mA