SC185

© 2010 Semtech Corp.

Electrical Characteristics

Exceeding the absolute maximum ratings may result in permanent damage to the device and/or device malfunction. Operation outside of the

parameters specified in the Electrical Characteristics section is not recommended.

Notes:

(7) Calculated from package in still air, mounted to 3” x 4.5”, 4 layer FR4 PCB with thermal vias under the exposed pad per JESD51 standards.

(8) Tested according to JEDEC standard JESD22-A114-B.

(9) Due to parasitic board inductance, the transient LX pin voltage at the point of measurement may appear larger than that which exists on silicon. The device is

designed to tolerate the short duration transient voltages that will appear on the LX pin due to the deadtime diode conduction, for inductor currents up to the

current limit setting of the device.

Recommended Operating Conditions

Supply Voltage PVIN and AVIN …………………… 2.9 to 5.5V

Maximum Output Current

………………………………… 4.0A

Temperature Range …………………………… -40 to +85˚C

Input Capacitor ………………………………………… 22uF

Output Capacitor ……………………… 47uF (or 2 x 22uF)

Output Inductor ……………………………………… 1.0uH

Thermal Resistance, Junction to Case …………… 7 °C/W

Maximum Junction Temperature …………………… +150°C

Storage Temperature Range ………………… -65 to +150 °C

Thermal Information

PVIN and AVIN Supply Voltages ………………… -0.3 to 6.0V

VOUT Voltage …………………………… -0.3 to AVIN+0.3V

CTLx pins Voltages ……………………… -0.3 to AVIN+0.3V

Peak IR Reflow Temperature …………………………. 260°C

Unless specified: PVIN= AVIN= 5.0V, VOUT= 1.50V, C

Parameter

Symbol

Conditions

Min

Typ

Max

Units

Under-Voltage Lockout

UVLO

Rising AVIN, PVIN=AVIN

2.70

2.80

2.90

V

Hysteresis

300

mV

ΔV

OUT

PVIN= AVIN= 2.9 – 5.5V; I

-1.25

+1.25

%

Current Limit

I

LIMIT

Peak LX current

5.0

6.0

7.0

A

Supply Current

I

Q

No load, MODE= High

12

mA

No load, MODE= Low

100

µA

Shutdown Current

I

SHDN

EN= AGND

1

10

µA

R

DSON_P

I

50

mΩ

R

DSON_N

I

35

L

(11)

I

LK(LX)

PVIN= AVIN= 5.5V; LX= 0V; EN= AGND

1

10

µA

PVIN= AVIN= 5.5V; LX= 5.0V; EN= AGND

-20

-1

Load Regulation

ΔV

LOAD-REG

PVIN= AVIN= 5.0V, MODE=Hi, I

±0.3

%

Oscillator Frequency

f

OSC

1.275

1.5

1.725

MHz

I

SS

+5

µA

Foldback Holding Current

I

CL_HOLD

Average LX Current

1

A

Absolute Maximum Ratings

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