SC653

5

Electrical Characteristics (continued)

Parameter

Symbol

Conditions

Min

Typ

Max

Units

Digital I/O Electrical Specifications (SPIF, ENL1, ENL2)

V

IH

V

IN

= 5.5V

1.6

V

V

IL

V

IN

= 3.0V

0.4

V

Input High Current

I

IH

V

IN

= 5.5V

-1

+1

μA

Input Low Current

I

IL

V

IN

= 5.5V

-1

+1

μA

SemPulse Electrical Specifications (SPIF)

t

SU

1ms

t

HI

0.75

250

μs

t

LO

0.75

250

μs

t

HOLDA

SPIF is held high

500

5000

μs

t

HOLDD

SPIF is held high

500

μs

t

BR

SPIF is held high

10

ms

t

SD

SPIF is pulled low

10

ms

Fault Protection

Output Short Circuit Current Limit

I

OUT(SC)

OUT pin shorted to GND

250

mA

LDO Current Limit

I

LIM

V

LDOn

enabled

200

mA

Over-Temperature

T

OTP

Rising threshold

165

°C

T

HYS

Hysteresis

30

°C

Charge Pump

Over-Voltage Protection

V

OVP

OUT pin open circuit, V

OUT

= V

OVP

rising threshold

5.3

5.7

6.0

V

Under Voltage Lockout

V

UVLO-OFF

Increasing V

IN

2.7

V

V

UVLO-HYS

Hysteresis

800

mV

Notes:

(1)

ΔV

F

is the voltage difference between any two LEDs.

(2)

SPIF is high for more than 10ms

(3)

Subscript n = 1 and 2 for the LDOs, and n = 1, 2, 3, and 4 for the backlights.

(4)

Current matching equals ± [I

BL(MAX)

- I

BL(MIN

] / [I

BL(MAX)

+ I

BL(MIN)

].

(5)

Test voltage is V

OUT

= 4.0V — a relatively extreme LED voltage — to force a transition during test. Typically V

OUT

= 3.2V for white LEDs.

(6)

Dropout is defined as (V

IN

- V

LDO1

) when V

LDO1

drops 100mV from nominal. Dropout does not apply to LDO2 since it has a maximum output voltage

of 1.8V.

(7)

The source driver used to provide the SemPulse output must meet these limits.

(8)

The SemPulse start-up time is the minimum time that the SPIF pin must be held high to enable the part before starting communication.

(9)

The SemPulse shutdown time is the minimum time that the SPIF pin must be pulled low to shut the part down.