Datasheet

MAX1570
White LED Current Regulator with 1x/1.5x
High-Efficiency Charge Pump
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS
(V
IN
= 3.6V, GND = PGND = 0, EN1 = EN2 = IN, C
IN
= C1 = C2 = 1µF, C
OUT
= 4.7µF, T
A
= -40°C to +85°C, unless otherwise noted.)
(Note 3)
PARAMETER CONDITIONS
MIN MAX
UNITS
IN Operating Voltage 2.7 5.5 V
Undervoltage Lockout Threshold
V
IN
rising or falling
2.25 2.60
V
Supply Current 1MHz switching, no load 3.5 mA
Shutdown Supply Current EN1 = EN2 = GND 5 µA
EN1 = GND, EN2 = IN, I
SET
= 33µA
0.190 0.210
EN1 = IN, EN2 = GND, I
SET
= 67µA
0.380 0.420
SET Bias Voltage
EN1 = IN, EN2 = IN, I
SET
= 100µA
0.570 0.630
V
SET Leakage in Shutdown EN1 = EN2 = GND, V
IN
= 5.5V, V
SET
= 0 or 5.5V 1 µA
SET Current Range 20
130
µA
SET to LED_ Current Ratio I
LED
/I
SET
, I
SET
= 67µA, V
LED_
= 1V 215
250
A/A
LED_ to LED_ Current Matching I
SET
= 67µA, V
LED_
= 1V -3 +3 %
Maximum LED_ Sink Current I
SET
= 130µA, V
LED_
= 1V 28 mA
I
SET
= 33µA (Note 1)
180
I
SET
= 67µA (Note 2)
360
LED_ Dropout Voltage
I
SET
= 100µA (Note 2)
410
mV
EN1 = GND, EN2 = IN, I
SET
= 33µA 185
215
EN1 = IN, EN2 = GND, I
SET
= 67µA
277
323
LED1 Regulation Voltage
(1.5x Mode)
EN1 = IN, EN2 = IN, I
SET
= 100µA 360
440
mV
LED Leakage in Shutdown EN1 = GND, EN2 = GND, V
LED_
= 5.5V 1 µA
Maximum OUT Current IN ≥ 3.4V, OUT ≥ 3.9V 150 mA
1x mode (V
IN
- V
OUT
)/I
OUT
1.75
Open-Loop OUT Resistance
1.5x mode (1.5V
IN
- V
OUT
)/I
OUT
8
Ω
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 1 µA
LED1 Dual Mode Threshold 50
100
mV
ELECTRICAL CHARACTERISTICS (continued)
(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
LED1 Dual Mode™ Threshold 50 75
100
mV
Thermal-Shutdown Threshold 160 °C
Thermal-Shutdown Hysteresis 20 °C
Dual Mode is a trademark of Maxim Integrated Products, Inc.
Note 1: Dropout voltage is defined as the LED_ to GND voltage at which current sink into LED_ drops 20% from the value at LED_ = 1V.
Note 2: Dropout voltage is defined as the LED_ to GND voltage at which current sink into LED_ drops 10% from the value at LED_ = 1V.
Note 3: Specifications to -40°C are guaranteed by design and not production tested.