MAX640 datasheet(3/12 Pages) MAXIM

3 / 12 page

5V/3.3V/3V/Adjustable, High-Efficiency,

Low IQ, Step-Down DC-DC Converters

_______________________________________________________________________________________

__________________________________________Typical Operating Characteristics

(Circuit of Figure 3, internal feedback, L = 100µH, TA = +25°C, unless otherwise noted.)

100

EFFICIENCY vs.

OUTPUT CURRENT

OUTPUT CURRENT (A)

10m

100m

L = 100

µH

+ = 9V

MAX639

MAX640

MAX653

100

EFFICIENCY vs.

OUTPUT CURRENT

OUTPUT CURRENT (A)

10m

MAX639, V+ = 6V

MAX640, V+ = 4.3V

MAX653, V+ = 4V

100m

L = 470

µH

100

EFFICIENCY vs.

OUTPUT CURRENT

OUTPUT CURRENT (A)

10m

MAX639

MAX640

MAX653

100m

L = 470

µH

V+ = 9V

Note 2: Output guaranteed by correlation to measurements of device parameters (i.e., switch on-resistance, on-times, off-times, and

output voltage trip points).

ELECTRICAL CHARACTERISTICS (continued)

(V+ = 9V for the MAX639, V+ = 5V for the MAX640/MAX653, ILOAD = 0mA, TA = TMIN to TMAX, typical values are at TA = +25°C,

unless otherwise noted.)

PARAMETER

0.4

1.2

MIN

TYP

MAX

VLBO = 0.4V

UNITS

LBO Leakage Current

0.001

0.1

µA

VLBO = 11.5V

LBO Delay

µs

50mV overdrive

2.5

SHDN Threshold

0.80

1.15

2.00

SHDN Pull-Up Current

0.10

0.20

0.40

Ω

µA

SHDN = 0V

µA

TA = +25°C

TA = TMIN to TMAX

MAX639

MAX640/MAX653

2.8

LX Switch Leakage

0.003

1.0

30.0

VFB Bias Current

4.0

15.0

VFB Dual-Mode Trip Point

LX Switch On-Resistance

0.8

1.5

VFB Threshold

1.26

1.28

1.30

1.24

1.28

1.32

LBI Bias Current

LBI Threshold

1.26

1.28

1.30

1.24

1.28

1.32

LBO Sink Current

0.8

2.5

CONDITIONS

V+ = 6V, TA = TMIN to TMAX, MAX639

V+ = 4V, TA = TMIN to TMAX, MAX640/MAX653

V+ = 11.5V, VLX = 0V

VFB = 2V

V+ = 9V, TA = +25°C, MAX639/MAX640/MAX653

MAX6_ _C

MAX6_ _E/M

VLBI = 2V

MAX6_ _C

MAX6_ _E/M

MAX640 Datasheet(PDF) 3 Page - Maxim Integrated Products

MAX640 Datasheet(HTML) 3 Page - Maxim Integrated Products

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12

Datasheet Download

Link URL