MC34270 Datasheet, PDF (1/12 Pages) Motorola, Inc – LIQUID CRYSTAL DISPLAY AND BACKLIGHT INTEGRATED CONTROLLER

Order this document by MC34270/D
Liquid Crystal Display and
Backlight Integrated Controller
MC34270
MC34271
The MC34270 and MC34271 are low power dual switching voltage
regulators, specifically designed for handheld and laptop applications, to
provide several regulated output voltages using a minimum of external parts.
Two uncommitted switching regulators feature a very low standby bias
current of 5.0 µA, and an operating current of 7.0 mA capable of supplying
output currents in excess of 200 mA.
Both devices have three additional features. The first is an ELD Output
that can be used to drive a backlight or a liquid crystal display. The ELD
output frequency is the clock divided by 256. The second feature allows
four additional output bias voltages, in specific proportions to VB, one of the
t ^{switching regulated output voltages. It allows use of mixed logic circuitry and}
provides a voltage bias for N–Channel load control MOSFETs . The third
feature is an Enable input that allows a logic level signal to turn–“off” or
turn–“on” both switching regulators.
Due to the low bias current specifications, these devices are ideally suited
for battery powered computer, consumer, and industrial equipment where an
extension of useful battery life is desirable.
LIQUID CRYSTAL DISPLAY
AND BACKLIGHT
INTEGRATED CONTROLLER
SEMICONDUCTOR
TECHNICAL DATA
32
1
MC34270 and MC34271 Features:
• Low Standby Bias Current of 5.0 µA
• Uncommitted Switching Regulators Allow Both Positive and Negative
Supply Voltages
• Logic Enable Allows Microprocessor Control of All Outputs
• Synchronizable to External Clock
• Mode Commandable for ELD and LCD Interface
• Frequency Synchronizable
• Auxiliary Output Bias Voltages Enable Load Control via N–Channel FETs
FB SUFFIX
PLASTIC PACKAGE
CASE 873
PIN CONNECTIONS
32 31 30 29 28 27 26 25
MOSFET is a trademark of Motorola, Inc.
1 DS1
DS2 24
2 Ref1
Ref2 23
MAXIMUM RATINGS (TA = 25°C, unless otherwise noted.)
Rating
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _{Input Voltage}
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _{Power Dissipation and}
Thermal Characteristics
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _{Maximum Power Dissipation}
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _{Case 873}
Symbol
VDD
Value
Unit
16
Vdc
PD
1.43
W
3 FB1
4 Comp1
5 SS1
6 S1
7 D1
FB2 22
Comp2 21
SS2 20
S2 19
D2 18
Thermal Resistance, Junction–to–Ambient
Thermal Resistance, Junction–to–Case
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _{Output #1 and #2 Switch Current}
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _{Output #1 and #2 “Off”–State Voltage}
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _{Feedback Enable MOSFETs “Off”–State Voltage}
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _{Operating Junction Temperature}
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _{Operating Ambient Temperature}
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _{Storage Temperature Range}
R_θJA
R_θJC
ISL & ISB
VSL
VLF
TJ
TA
Tstg
100
60
500
60
20
125
0 to +70
– 55 to +150
°C/W
°C/W
mA
Vdc
Vdc
°C
°C
°C
8 Drv1
VB 17
9 10 11 12 13 14 15 16
ORDERING INFORMATION
Device
Operating
Temperature Range Package
MC34270FB
MC34271FB
TA = 0° to +70°C
QFP–32
QFP–32
MOTOROLA ANALOG IC DEVICE DATA
© Motorola, Inc. 1996
Rev 1
1