Electrical characteristics (continued) – Rainbow Electronics MAX1885 User Manual

Page 4

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MAX1778/MAX1880–MAX1885

Quad-Output TFT LCD DC-DC
Converters with Buffer

4

_______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(V

IN

= +3.0V, SHDN = IN, V

SUPP

= V

SUPN

= V

SUPB

= V

SUPL

= 10V, LDOOUT = FBL, BUF- = BUFOUT, BUF+ = FLTSET = TGND =

PGND = GND, C

REF

= 0.22µF, C

BUF

= 1µF, T

A

= 0°C to +85°C. Typical values are at T

A

= +25°C, unless otherwise noted.)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

NEGATIVE CHARGE PUMP (MAX1778/MAX1880/MAX1881/MAX1882 ONLY)

SUPN Input Supply Range

V

SUPN

2.7

13

V

Operating Frequency

f

CHP

0.5 x f

OSC

Hz

FBN Regulation Voltage

V

FBN

-50

0

+50

mV

FBN Input Bias Current

I

FBN

V

FBN

= 0

-50

+50

nA

DRVN PCH On-Resistance

R

PCH(ON)

5

10

V

FBN

= +50mV

2

4

DRVN NCH On-Resistance

R

NCH(ON)

V

FBN

= -50mV

20

k

Maximum RMS DRVN Current

0.1

A

FBN Power-Ready Trip Level

Falling edge

80

125

165

mV

FBN Fault Trip Level

Rising edge

80

140

190

mV

LOW-DROPOUT LINEAR REGULATOR (MAX1778/MAX1881/MAX1883/MAX1884 ONLY)

SUPL Input Supply Range

V

SUPL

4.5

15

V

SUPL Undervoltage Lockout

Rising edge, 50mV hysteresis (typ)

3.8

4

4.3

V

SUPL Quiescent Current

I

SUPL

I

LDO

= 100µA

120

220

µA

I

LDO

= 40mA

130

300

Dropout Voltage (Note 1)

V

DROP

LDO is set to
regulate at 9V

I

LDO

= 5mA

70

mV

FBL Regulation Voltage

V

FBL

V

SUPL

= 10V, LDO regulating at 9V,

I

LDO

= 15mA

1.235

1.25

1.265

V

LDO Load Regulation

V

SUPL

= 10V, LDO regulating at 9V,

I

LDO

= 100µA to 40mA

1.2

%

LDO Line Regulation

V

SUPL

= 4.5V to 15V, FBL = LDOOUT,

I

LDO

= 15mA

0.02

%/V

FBL Input Bias Current

I

FBL

V

FBL

= 1.25V

-0.8

+0.8

µA

LDO Current Limit

I

LDOLIM

V

SUPL

= 10V, V

LDOOUT

= 9V, V

FBL

= 1.2V

40

130

220

mA

VCOM BUFFER

SUPB Input Supply Range

V

SUPB

4.5

13

V

SUPB Quiescent Current

I

SUPB

V

SUPB

= 13V

420

850

µA

BUFOUT Leakage Current

-10

+10

µA

Power-Supply Rejection Ratio

PSRR

V

SUPB

= 4.5V to 13V, V

CM

= 2.25V

85

98

dB

Input Common-Mode Voltage
Range

V

CM

|V

OS

| < 10mV

1.2

8.8

V

Common-Mode Rejection Ratio

CMRR

V

CM

= 1.2V to 8.8V

75

dB

Input Bias Current

I

BIAS

V

CM

= 5V

-100

-10

+100

nA

Input Offset Current

I

OS

V

CM

= 5V

-100

+100

nA

Gain Bandwidth Product

GBW

C

BUF

= 1µF

13

kHz

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