Rainbow Electronics MAX1554 User Manual
Page 2
MAX1553/MAX1554
High-Efficiency, 40V Step-Up
Converters for 2 to 10 White LEDs
2
_______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(V
CC
= 3.3V, V
OV
= 0V, C
OUT
= 1µF, R
SENSE
= 10
Ω, T
A
= 0°C to +85°C, unless otherwise noted. Typical values are at T
A
= +25
°C.)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
V
CC
, FB, OV to GND..............................................-0.3V to +6.0V
LX to GND ..............................................................-0.3V to +45V
EN, BRT, SS to GND...................................-0.3V to (V
CC
+ 0.3V)
I
LX
...................................................................................0.9A
RMS
Continuous Power Dissipation (T
A
= +70°C)
8-Pin 3mm x 3mm TDFN
(derate 24.4mW/°C above +70°C) .............................1951mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
MAX1553
2.7
5.5
Supply Voltage
MAX1554
3.15
5.50
V
Undervoltage Lockout Threshold
V
CC
rising or falling, 35mV hysteresis typical
2.35
2.5
2.65
V
Not switching
0.33
0.65
Quiescent Current
Switching
0.44
0.9
mA
T
A
= +25°C
0.1
1
Shutdown Supply Current
V
EN
= 0V
T
A
= +85°C
1
µA
OV Threshold
Rising edge
1.18
1.25
1.33
V
T
A
= +25°C
1
200
OV Input Bias Current
V
OV
= 1V
T
A
= +85°C
10
nA
BRT Input Resistance
0 < V
BRT
< 1.5V, EN = V
CC
200
400
600
k
Ω
TIMING CONTROL
Maximum On-Time
V
CC
= 3.3V
2.0
3.4
4.8
µs
On-Time Constant (K)
t
ON
= K / V
CC
6.3
µs-V
Minimum Off-Time
150
250
350
ns
ERROR AMPLIFIER
V
BRT
= 1.25V
192
203
212
FB Threshold
V
BRT
= 3.3V
280
mV
T
A
= +25°C
15
200
FB Input Bias Current
V
FB
= 1.0V
T
A
= +85°C
100
nA
N-CHANNEL SWITCH
LX On-Resistance
0.8
1.4
Ω