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Typical operating characteristics – Rainbow Electronics MAX8884Z User Manual

Page 4

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MAX8884Y/MAX8884Z

700mA DC-DC Step-Down Converters
with Dual 300mA LDO in 2mm x 2mm CSP

4

_______________________________________________________________________________________

STEP-DOWN CONVERTER EFFICIENCY

vs. LOAD CURRENT, V

OUT

= 1.8V

MAX8884Y/Z toc01

LOAD CURRENT (mA)

EFFICIENCY (%)

100

10

40

50

60

70

80

90

100

30

1

1000

MAX8884Y, V

IN

= 3.2V

= 3.6V
= 4.2V

MAX8884Z, V

IN

= 3.2V

= 3.6V
= 4.2V

STEP-DOWN CONVERTER EFFICIENCY

vs. LOAD CURRENT, V

OUT

= 1.2V

MAX8884Y/Z toc02

LOAD CURRENT (mA)

EFFICIENCY (%)

100

10

40

50

60

70

80

90

100

30

1

1000

MAX8884Y, V

IN

= 3.2V

= 3.6V
= 4.2V

MAX8884Z, V

IN

= 3.2V

= 3.6V
= 4.2V

STEP-DOWN CONVERTER NO-LOAD

SUPPLY CURRENT vs. INPUT VOLTAGE

MAX8884Y/Z toc03

INPUT VOLTAGE (V)

SUPPLY CURRENT (

μ

A)

5

4

3

2

1

50

100

150

200

250

300

0

0

6

V

BUCK_EN

= V

IN

V

LDO1_EN

= V

LDO2_EN

= 0

V

IN

FALLING

V

IN

RISING

MAX8884Y

MAX8884Z

STEP-DOWN OUTPUT VOLTAGE vs. LOAD

CURRENT (VOLTAGE POSITIONING)

MAX8884Y/Z toc04

LOAD CURRENT (mA)

OUTPUT VOLTAGE (V)

100

10

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.8

1.9

1.0

1

1000

SEL = IN1_

SEL = AGND

MAX8884Z STEP-DOWN CONVERTER

LIGHT LOAD SWITCHING WAVEFORMS

MAX8884Y/Z toc05

400ns/div

I

LX

V

OUT

V

LX

0A

2V/div

100mA/div

AC-COUPLED
20mV/div

0V

MAX8884Y STEP-DOWN CONVERTER

LIGHT LOAD SWITCHING WAVEFORMS

MAX8884Y/Z toc06

1

μs/div

I

LX

V

OUT

V

LX

0A

2V/div

100mA/div

AC-COUPLED
10mV/div

0V

I

LOAD

= 50mA

MAX8884Z STEP-DOWN CONVERTER

HEAVY LOAD SWITCHING WAVEFORMS

MAX8884Y/Z toc07

200ns/div

I

LX

V

OUT

V

LX

0A

2V/div

500mA/div

AC-COUPLED
10mV/div

0V

I

LOAD

= 500mA

MAX8884Y STEP-DOWN CONVERTER

HEAVY LOAD SWITCHING WAVEFORMS

MAX8884Y/Z toc08

400ns/div

I

LX

V

OUT

V

LX

0A

2V/div

500mA/div

AC-COUPLED
10mV/div

0V

I

LOAD

= 500mA

Typical Operating Characteristics

(V

IN

= V

IN1A

= V

IN1B

= V

IN2

= 3.6V, V

BUCK

= 1.2V, V

LDO1

= 1.8V, V

LDO2

= 2.8V, MAX8884YEVKIT, T

A

= +25°C, unless otherwise noted.)