Preliminary

Rev.01

3/16

EP1551

Absolute Maximum Rating

(Note 1)

OUTBU_, INSD, SDOK, ON_, FB_, FBSEL_ to GND................................ -0.3V to +6V

PGND to GND ........................................................................................ -0.3V to +0.3V

DL_to PGND...............................................................................-0.3V to OUTSU+0.3V

LXSU Current

LXSD Current

REF, OSC, COMP_ to GND........................................................-0.3V to OUTSU+0.3V

Continuous Power Dissipation (TA=70°C, derate 22mW/°C above +70°C)......1700Mw

Operating Temperature Range.............................................................. -40°C to +85°C

Junction Temperature ........................................................................................+150°C

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

Lead Temperature (Soldering, 10s) ...................................................................+150°C

Note 1:

Absolute Maximum Ratings are those values beyond which the life of a device may be impaired.

Note 2:

LXSU has internal clamp diodes to OUTSU and PGND, and LXSD has internal clamp diodes to

INSD and PGND. Applications that forward bias these diodes should take care not to exceed the

devices power dissipation limits.

Electrical Characteristics

(VOUTSU = 3.3V, TA = 0°C to +85°C, unless otherwise noted.)

Parameter

Conditions

MIN

TYP

MAX

unit

GENERAL:

Input Voltage Range

0.7

5.5

V

Minimum Startup Voltage

ILOAD < 1mA, TA = +25°C

1.2

1.4

V

Thermal Shutdown

160

°C

Thermal-Shutdown Hysteresis

20

°C

Shutdown Supply Current into

OUTSU

ONSU = ONSD = ON1 = ON2 = ON3

= 0, OUTSU = 3.6V

0.3

5

µA

Step-up DC-DC Supply Current

into OUTSU

ONSU = 3.35v, FBSU = 1.5V (does

not include switching losses)

320

400

µA

Step-up Plus 1 AUX Supply

Current into OUTSU

ONSU = ON_ = 3.35V,

FBSU = 1.5V, FB_= 1.5V

(does not include switching losses)

385

600

µA

Step-up Plus Step-down

Supply Current into OUTSU

ONSU = ONSD = 3.35V, FBSU =

1.5V, FBSD = 1.5V (does not include

switching losses)

1030

1300

µA

Reference Output Voltage

IREF = 20 µA

1.225

1.25

1.275

V

Reference Load Regulation

10µA < IREF < 200µA

4.5

10

mV

Reference Line Regulation

2.7 < OUTSU < 5.5V

1.3

5

mV

OSC Discharge Trip Level

Rising edge

1.225

1.25

1.275

V

OSC Discharge Resistance

OSC = 1.5v, IOSC = 3mA

52

80

Ω

OSC Discharge Pulse Width

230

ns

OSC Frequency

ROSC = 40K., COSC = 100pF

400

KHz