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Typical operating characteristics, Electrical characteristics (continued) – Rainbow Electronics MAX15001 User Manual

Page 4

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MAX15000/MAX15001

Current-Mode PWM Controllers with
Programmable Switching Frequency

4

_______________________________________________________________________________________

Note 1: All devices are 100% tested at T

A

= +85°C. All limits over temperature are guaranteed by characterization.

Note 2: The MAX15000 is intended for use in universal input power supplies. The internal clamp circuit at IN is used to prevent the

bootstrap capacitor (C1 in Figure 1) from charging to a voltage beyond the absolute maximum rating of the device when
UVLO/EN is low (shutdown mode). Externally limit the maximum current to IN (hence to clamp) to 2mA maximum when
UVLO/EN is low. Clamp currents higher than 2mA may result in a clamp voltage higher than 30V, thus exceeding the
absolute maximum rating for IN. For the MAX15001, do not exceed the 24V maximum operating voltage of the device.

Note 3: V

REF

is measured with FB connected to COMP (see the Functional Diagram).

Note 4: The oscillator in the MAX1500_A is capable of operating up to 2500kHz. However, the NDRV switching frequency is limited

to operate up to 625kHz. Thus, the oscillator frequency for MAX1500_A must be limited to 1250kHz (maximum).

ELECTRICAL CHARACTERISTICS (continued)

(V

IN

= +12V (for MAX15000, bring V

IN

up to 23.6V for startup), 10nF bypass capacitors at IN and V

CC

, R12 = 15k

Ω (MAX1500_A), R12

= 7.5k

Ω (MAX1500_B), R15 = 1kΩ, C6 = 100nF (see the Typical Application Circuit), NDRV = open, V

UVLO/EN

= +1.4V, V

FB

= +1.0V,

COMP = open, V

CS

= 0V, T

A

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

A

= +25°C.) (Note 1)

BOOTSTRAP UVLO WAKE-UP LEVEL

vs. TEMPERATURE

MAX15000 toc01

TEMPERATURE (

°C)

V

IN

(V)

60

35

10

-15

21.4

21.5

21.6

21.7

21.8

21.3

-40

85

MAX15000 V

IN

RISING

BOOTSTRAP UVLO SHUTDOWN LEVEL

vs. TEMPERATURE

MAX15000 toc02

TEMPERATURE (

°C)

V

IN

(V)

60

35

10

-15

9.5

9.7

9.9

10.1

10.3

9.3

-40

85

MAX15000 V

IN

FALLING

UVLO/EN WAKE-UP THRESHOLD

vs. TEMPERATURE

MAX15000 toc03

TEMPERATURE (

°C)

UVLO/EN (V)

60

35

10

-15

1.226

1.228

1.230

1.232

1.234

1.236

1.224

-40

85

UVLO/EN RISING

Typical Operating Characteristics

(V

UVLO/EN

= +1.4V, V

FB

= +1V, COMP = open, V

CS

= 0V, T

A

= +25°C, unless otherwise noted.)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

OSCILLATOR

Oscillator Frequency Range

f

OSC

50

2500

kHz

f

OSC

= 200kHz to 800kHz

-10

+10

Oscillator Frequency Accuracy

f

OSC

= 50kHz to 2500kHz

-20

+20

%

MAX1500_A, f

SW

= f

OSC

/2

25

625

NDRV Switching Frequency
(Note 4)

f

SW

MAX1500_B, f

SW

= f

OSC

/4

12.5

625.0

kHz

MAX1500_A

50

Maximum Duty Cycle

D

MAX

MAX1500_B

75

%