Datasheet

MAX1570
White LED Current Regulator with 1x/1.5x
High-Efficiency Charge Pump
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
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.
IN, OUT, EN1, EN2 to GND ......................................-0.3V to +6V
SET, LED1, LED2, LED3, LED4,
LED5 to GND ...........................................-0.3V to (V
IN
+ 0.3V)
PGND to GND..........................................................-0.3 to +0.3V
C1N, C2N to GND ..........................................-0.3V to (V
IN
+ 1V)
C1P, C2P to GND ..........................................-0.3V to the greater
(V
OUT
+ 1V) or (V
IN
+ 1V)
OUT Short Circuit to GND..............................................Indefinite
Continuous Power Dissipation (T
A
= +70°C)
16-Pin Thin QFN (derate 16.9 mW/°C).......................1349mW
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
ELECTRICAL CHARACTERISTICS
(V
IN
= 3.6V, GND = PGND = 0, EN1 = EN2 = IN, C
IN
= C1 = C2 = 1µF, C
OUT
= 4.7µF, T
A
= 0°C to +85°C, unless otherwise noted.
Typical values are at T
A
= +25°C.)
PARAMETER CONDITIONS
MIN TYP MAX
UNITS
IN Operating Voltage 2.7 5.5 V
Undervoltage Lockout Threshold
V
IN
rising or falling
2.25 2.45 2.60
V
Undervoltage Lockout Hysteresis
35 mV
Supply Current 1MHz switching, no load 2.0 3.5 mA
Shutdown Supply Current EN1 = EN2 = GND 0.1 5 µA
Soft-Start Done Time 2.1 ms
EN1 = GND, EN2 = IN, I
SET
= 33µA
0.190 0.200 0.210
EN1 = IN, EN2 = GND, I
SET
= 67µA
0.380 0.400 0.420
SET Bias Voltage
EN1 = IN, EN2 = IN, I
SET
= 100µA
0.570 0.600 0.630
V
SET Leakage in Shutdown EN1 = EN2 = GND, V
IN
= 5.5V, V
SET
= 0 or 5.5V
0.01 1.00
µA
SET Current Range 20
130
µA
SET to LED_ Current Ratio I
LED
/I
SET
, I
SET
= 67µA, V
LED_
= 1V
215
230
245
A/A
LED_ to LED_ Current Matching I
SET
= 67µA, V
LED_
= 1V -3 0.3 +3 %
Maximum LED_ Sink Current I
SET
= 130µA, V
LED_
= 1V 28 30 mA
I
SET
= 33µA (Note 1) 100
180
I
SET
= 67µA (Note 2) 200
360
LED_ Dropout Voltage
I
SET
= 100µA (Note 2) 230
410
mV
EN1 = GND, EN2 = IN, I
SET
= 33µA
185
200
215
EN1 = IN, EN2 = GND, I
SET
= 67µA
277
300
323
LED1 Regulation Voltage
(1.5x Mode)
EN1 = IN, EN2 = IN, I
SET
= 100µA
360
400
440
mV
LED Leakage in Shutdown EN1 = GND, EN2 = GND, V
LED_
= 5.5V
0.01 1.00
µA
Maximum OUT Current IN ≥ 3.4V, OUT ≥ 3.9V
150
mA
1x mode (V
IN
- V
OUT
)/I
OUT
1.00 1.75
Open-Loop OUT Resistance
1.5x mode (1.5V
IN
- V
OUT
)/I
OUT
8
Ω
Switching Frequency 1 MHz
EN1, EN2 High Voltage IN = 2.7V to 5.5V 1.6 V
EN1, EN2 Low Voltage IN = 2.7V to 5.5V 0.4 V
EN1, EN2 Input Current EN_ = GND or 5.5V
0.01 1.00
µA