MAX849 MAXIM [Maxim Integrated Products], MAX849 Datasheet - Page 4

• Manufacturer Part Number: MAX849
• Description: 1-Cell to 3-Cell, High-Power, Low-Noise, Step-Up DC-DC Converters
• Manufacturer: MAXIM [Maxim Integrated Products]

ELECTRICAL CHARACTERISTICS
(V
unless otherwise noted.) (Note 9)
1-Cell to 3-Cell, High-Power,
Low-Noise, Step-Up DC-DC Converters
Note 1: Minimum operating voltage. Because the MAX848/MAX849 are bootstrapped to the output, it will operate down to a 0.7V input.
Note 2: In low-power mode (CLK/SEL = GND), the output voltage regulates 1% higher than in low-noise mode (CLK/SEL = OUT or
Note 3: The part is in start-up mode until it reaches this voltage level. Do not apply full-load current.
Note 4: Load regulation is measured from no load to full load, where full load is determined by the N-channel switch current limit.
Note 5: Start-up is tested with Figure 2’s circuit. Output current is measured when the input and output voltages are applied.
Note 6: Supply current from the 3.34V output is measured between the 3.34V output and the OUT pin. This current correlates directly
Note 7: When V
Note 8: ON1 and ON2 inputs have approximately 0.15V
Note 9: Specifications to -40°C are guaranteed by design, not production tested.
4
REFERENCE
DC-DC CONVERTER
DC-DC SWITCHES
ADC
POWER-GOOD
LOGIC CONTROL INPUTS
Reference Output Voltage
Output Voltage (Note 3)
FB Regulation Voltage
Output Voltage Lockout Range
OUT Supply Current in Shutdown
OUT Supply Current in Low-Power
Mode (Note 6)
OUT Supply Current in Low-Noise
Mode (Note 6)
Switch On-Resistance
N-Channel Current Limit
Accuracy
Internal Trip Level
External Trip Level
Internal Oscillator Frequency
Oscillator Maximum Duty Cycle
OUT
_______________________________________________________________________________________
= 3.6V, GND = PGND = CLK/SEL = ON1 = ON2 = AINSEL = AIN1 = AIN2 = FB = POKIN, POUT = OUT, T
synchronized).
with actual battery supply current, but is reduced in value according to the step-up ratio and efficiency. V
the internal switch open when measuring the current into the device.
testing in Figure 2’s circuit.
PARAMETER
CLK/SEL
= 0V, the inductor is forced into constant-peak-current, discontinuous operation. This is guaranteed by
I
V
includes load-regulation error
Adjustable output, CLK/SEL = OUT
(Note 3)
V
CLK/SEL = GND
CLK/SEL = OUT, does not include
switching losses
f
Rising V
Rising V
CLK/SEL = OUT
N-channel
P-channel
CLK/SEL = OUT
CLK/SEL = GND (Note 7)
REF
CLK
FB
ON2
< 0.1V, CLK/SEL = OUT,
= 0mA
= 400kHz, 5ms conversion
= 3.6V
OUT
POKIN
, V
OUT
CONDITIONS
POKIN
hysteresis.
< 0.1V
CLK/SEL = GND
CLK/SEL = OUT
CLK/SEL = OUT
MAX848
MAX849
MAX848
MAX849
1.225
1.225
1100
MIN
3.13
1.21
2.05
2.95
600
120
250
260
80
TYP
1.275
1.275
MAX
1100
1800
OUT
3.47
1.27
2.45
0.25
3.10
A
300
300
550
340
0.6
0.5
±4
20
90
90
= -40°C to +85°C,
= 3.6V to keep
UNITS
% FSR
kHz
mA
µA
µA
µA
%
Ω
V
V
V
V
V
V