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Typical operating characteristics, Electrical characteristics (continued) – Rainbow Electronics MAX8645Y User Manual

Page 4

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MAX8645X/MAX8645Y

1x/1.5x/2x White LED Charge Pumps with
Two LDOs in 4mm x 4mm TQFN

4

_______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(V

IN

= 3.6V, V

GND

= V

PGND

= 0V, ENM1 = ENM2 = ENF = IN, R

SETM

= R

SETF

= 6.8k

Ω, P1 = P2 = unconnected, C

REF

= 0.01µF,

T

A

= -40°C to +85°C, unless otherwise noted. Typical values are at T

A

= +25°C.) (Note 1)

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

Soft-Start Done Time

100

µs

Dropout Voltage

I

LDO_

= 200mA (Note 4)

120

320

mV

Load Regulation

V

IN

= 3.7V, 100µA < I

LDO_

< 200mA

1.3

%

Power-Supply Rejection
ΔV

OUT

/

ΔV

IN

10Hz to 10kHz, C

LDO_

= 1µF, I

LDO_

= 10µA

-60

dB

Output Noise Voltage (RMS)

10Hz to 100kHz, C

LDO_

= 1µF, I

LDO_

= 10mA

40

µV

RMS

Note 1: All devices are 100% production tested at T

A

= +25°C. Limits over the operating temperature range are guaranteed by

design.

Note 2: LED dropout voltage is defined as the M_ or F_ to GND voltage at which current into M_ or F_ drops 10% from the value at

M_ or F_ = 0.2V.

Note 3: (Greater of 2.7V or (V

LDO_

+ 0.5V))

≤ V

IN

≤ 5.5V.

Note 4: LDO dropout voltage is defined as V

IN

- V

OUT

when V

OUT

is 100mV below the value of V

OUT

measured when V

IN

=

V

OUT(NOM)

+ 1V. Since the minimum input voltage is 2.7V, this specification is only meaningful when V

OUT(NOM)

> 2.5V.

Typical Operating Characteristics

(V

IN

= V

EN_

= 3.6V, circuit of Figure 2, T

A

= +25°C, unless otherwise noted.)

EFFICIENCY vs. Li+ BATTERY

VOLTAGE DRIVING SIX MAIN LEDs

MAX8645Y toc01

Li+ BATTERY VOLTAGE (V)

EFFICIENCY P

LED

/P

BATT

(%)

3.9

3.6

3.3

3.0

50

60

70

80

90

100

40

2.7

4.2

15mA/LED

4.5mA/LED

1.5mA/LED

EFFICIENCY vs. Li+ BATTERY

VOLTAGE DRIVING FLASH LED MODULE

MAX8645Y toc02

Li+ BATTERY VOLTAGE (V)

EFFICIENCY P

LED

/P

BATT

(%)

3.9

3.6

3.3

3.0

50

60

70

80

90

100

40

2.7

4.2

80mA TOTAL

160mA TOTAL

400mA TOTAL

BATTERY CURRENT vs. SUPPLY VOLTAGE

DRIVING SIX MAIN LEDs

MAX8645Y toc03

SUPPLY VOLTAGE (V)

BATTERY CURRENT (mA)

3.9

3.6

3.3

3.0

30

60

90

120

150

180

0

2.7

4.2

I

LED

= 15mA

I

LED

= 4.5mA

I

LED

= 1.5mA

V

IN

FALLING

V

IN

RISING