LM2841 datasheet(4/19 Pages) TI1

4 / 19 page

LM2841, LM2842

SNVS540H – MARCH 2009 – REVISED APRIL 2013

www.ti.com

Electrical Characteristics (continued)

Specifications in standard type face are for TJ = 25°C and those with boldface type apply over the full Operating

Temperature Range ( TJ = −40°C to +125°C). Minimum and Maximum limits are specified through test, design, or statistical

correlation. Typical values represent the most likely parametric norm at TJ = +25°C, and are provided for reference purposes

only. Unless otherwise stated the following conditions apply: VIN = 12V.

Symbol

Parameter

Conditions

Min (1)

Typ (2)

Max (1)

Units

tON(min)

Minimum ON time

See (6)

100

150

tOFF(min)

Minimum OFF time

X option

110

370

Y option

104

200

fSW

LM2840/41/42X, VFB = 0.5V

325

550

750

kHz

LM2840/41/42X, VFB = 0V

140

Switching frequency

LM2840/41/42Y, VFB = 0.5V

0.95

1.25

1.50

MHz

LM2840/41/42Y, VFB = 0V

0.35

DMAX

Maximum duty cycle

LM2840/41/42X

LM2840/41/42Y

VUVP

Undervoltage lockout

On threshold

4.4

3.7

thresholds

Off threshold

3.5

3.25

V SHDN

Shutdown threshold

Device on

2.3

1.0

Device off

0.9

0.3

ISHDN

Shutdown pin input bias current VSHDN = 2.3V

(5)

0.05

1.5

µA

VSHDN = 0V

0.02

1.5

THERMAL SPECIFICATIONS

RθJA

Junction-to-Ambient Thermal

See (7)

121

°C/W

Resistance, SOT-6L Package

RθJC

Junction-to-Case Thermal

°C/W

Resistance, SOT-6L Package

(6)

Minimum On Time specified by design and simulation.

(7)

All numbers apply for packages soldered directly onto a 3" x 3" PC board with 2 oz. copper on 4 layers in still air in accordance to

JEDEC standards. Thermal resistance varies greatly with layout, copper thickness, number of layers in PCB, power distribution, number

of thermal vias, board size, ambient temperature, and air flow.

Submit Documentation Feedback

Product Folder Links: LM2841 LM2842

LM2841 Datasheet(PDF) 4 Page - Texas Instruments

LM2841 Datasheet(HTML) 4 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19

Datasheet Download

Link URL