DA6251.002

27 October, 2017

3 (21)

RECOMMENDED OPERATING CONDITIONS

All voltages with respect to ground.

Parameter

Symbol

Conditions

Min

Typ

Max

Unit

Operating Supply Voltage

Note 1

1.2

3.0

5.5

V

Steady State Operating

Output Voltage

Note 2

VIN+1V

V

Operating Ambient

Temperature

Note 3

-40

+27

+85

°C

Operating Junction

Temperature

Note 4

-40

+125

°C

Inductor Specification

L

Shielded inductor

Note 5

1.5

2.2

3

H

L=2.2

H

500

600

mA

L=2.2

H

0.18

0.5

Ω

Peak Inductor Current

VIN=3.0V, VOUT=15V, L=2.2

H

480

mA

Piezo Resonance

Frequency

3.8

10

kHz

LED PWM Dimming

Signal

CTRL signal frequency

150

3000

Hz

CTRL signal ON-time

30

µs

Note 1: Achieving minimum operating supply voltage 1.2V requires a low loss inductor. See note 5 for two low loss inductor examples. When

driving LEDs or resistive load the minimum supply voltage can be higher than specified here. See figures 20-22 for output current drive

capability at LED and resistive loading.

Note 2: For stable start-up and good output regulation the steady state output voltage (VOUT) should meet following condition;

VOUT≥VIN+1V. When driving one or two LEDs the output voltage may not satisfy this requirement but depending on input voltage. In this

case there can be added resistor in series with LED(s) to rise output voltage above the minimum requirement.

Note 3: Ambient temperature plus self-heating should not exceed +125°C in extended periods of time to not degrade EEPROM memory data

retention time. Additionally user has to note that the on chip thermal shutdown feature can turn off the device at minimum +140°C rising

temperature point.

Note 4: On chip EEPROM memory storing factory trimming values has data retention of minimum 10 years at +125°C.

Note 5: For small PCB footprint a 2x1.6x0.7mm (0806) size 2.2

H inductor is available from Murata (LQM2MPN2R2MEH#). For high

efficiency a 3x3x1.2mm size 2.2µH inductor is available from Taiyo Yuden (NR3012T2R2M).