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Max1747 triple charge-pump tft lcd dc-dc converter, Typical operating characteristics, Electrical characteristics (continued) – Rainbow Electronics MAX1747 User Manual

Page 5

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MAX1747

Triple Charge-Pump TFT LCD

DC-DC Converter

_______________________________________________________________________________________

5

PARAMETER

SYMBOL

CONDITIONS

MIN

MAX

UNITS

REFERENCE

Reference Voltage

V

REF

-2

µA < I

REF

< 50

µA

1.222

1.269

V

Reference Undervoltage
Threshold

V

REF

rising

0.95

1.18

V

LOGIC SIGNALS

SHDN Input Low Voltage

0.4

V

SHDN Bias Voltage

I

SHDN

= 22

µA

580

900

mV

SHDN Input Current Range

I

SHDN

For 200kHz to 2MHz operation

3

65

µA

RDY Output Low Voltage

I

SINK

= 2mA

0.5

V

RDY Output High Leakage

V

RDY

= 13V

1

µA

ELECTRICAL CHARACTERISTICS (continued)

(

V

IN

= V

SUPM

= +3.0V, V

SUPP

= V

SUPM

= +5V, TGND = PGND = GND, I

SHDN

= 22µA, C

OUT

= 2

4.7µF, C

REF

= 0.22µF, C

INTG

=

1500pF, V

OUT

= +5V, T

A

= -40°C to +85°C, unless otherwise noted.) (Note 1)

Note 1: Specifications from 0

°C to -40°C are guaranteed by design, not production tested.

Typical Operating Characteristics

(Circuit of Figure 1, V

IN

= V

SUPM

= +3.3V, T

A

= +25°C, unless otherwise noted.)

4.97

4.99

4.98

5.01

5.00

5.02

5.03

0

200

100

300

400

MAX1747 toc01

I

OUT

(mA)

V

OUT

(V)

MAIN OUTPUT EFFICIENCY

vs. LOAD CURRENT

(MAIN CHARGE PUMP ONLY)

V

IN

= 3.3V

V

IN

= 4.0V

V

IN

= 2.8V

40

60

50

80

70

90

100

0

200

100

300

400

MAX1747 toc02

I

OUT

(mA)

EFFICIENCY (%)

MAIN OUTPUT EFFICIENCY

vs. LOAD CURRENT

(MAIN CHARGE PUMP ONLY)

V

OUT

= 5V

V

IN

= 3.3V

V

IN

= 4.0V

V

IN

= 2.8V

40

60

50

80

70

90

100

0

200

100

300

400

MAX1747 toc03

I

OUT

(mA)

EFFICIENCY (%)

MAIN OUTPUT EFFICIENCY

vs. LOAD CURRENT

(MAIN CHARGE PUMP ONLY)

V

OUT

= 5V

V

IN

= 3.3V

V

IN

= 4.0V

V

IN

= 2.8V

V

NEG

= -7V WITH I

NEG

= 10mA

V

POS

= 12V WITH I

POS

= 5mA