Sharp AQUOS LC-42LE40E, Service Manual

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LC-32LE40E-LC-42LE40E
61
2.7 U4053(ICL3232ECV)
General Description
The Intersil ICL32xxE devices are 3.0V to 5.5V powered RS-232 transmitters/receivers which meet ElA/TIA-232 and V.28/V.24 specifications, even at
VCC = 3.0V. Additionally, they provide ±15kV ESD protection (IEC61000-4-2 Air Gap and Human Body Model) on transmitter outputs and receiver inputs
(RS-232 pins). Targeted applications are PDAs, Palmtops, and notebook and laptop computers where the low operational, and even lower standby, power
consumption is critical. Efficient on-chip charge pumps, coupled with manual and automatic power-down functions(except for the ICL3232E), reduce the
standby supply current to a 1 μ A trickle. Small footprint packaging, and the use of small, low value capacitors ensure board space savings as well. Data
rates greater than 250kbps are guaranteed at worst case load conditions. This family is fully compatible with 3.3V-only systems, mixed 3.3V and 5.0V
systems, and 5.0V-only systems.
The ICL324XE are 3-driver, 5-receiver devices that provide a complete serial port suitable for laptop or notebook computers. Both devices also include
noninverting always-active receivers for “wake-up” capability.
The ICL3221E, ICL3223E and ICL3243E, feature an automatic power-down function which powers down the on-chip power-supply and driver circuits. This
occurs when an attached peripheral device is shut off or the RS-232 cable is removed, conserving system power automatically without changes to the
hardware or operating system. These devices power up again when a valid RS-232 voltage is applied to any receiver input.
Table 1 summarizes the features of the devices represented by this data sheet, while Application Note AN9863 summarizes the features of each device
comprising the ICL32xxE 3V family.
Features
• ESD Protection for RS-232 I/O Pins to ±15kV (IEC61000)
• Drop in Replacements for MAX3221E, MAX3222E, MAX3223E, MAX3232E, MAX3241E, MAX3243E, SP3243E
• ICL3221E is a Low Power, Pin Compatible Upgrade for 5V MAX221E
• ICL3222E is a Low Power, Pin Compatible Upgrade for 5V MAX242E, and SP312E
• ICL3232E is a Low Power Upgrade for HIN232E, ICL232 and Pin Compatible Competitor Devices
• RS-232 Compatible with VCC = 2.7V
• Meets EIA/TIA-232 and V.28/V.24 Specifications at 3V
• Latch-Up Free
• On-Chip Voltage Converters Require Only Four External 0.1 μ F Capacitors
• Manual and Automatic Power-down Features
• Guaranteed Mouse Driveability (ICL324XE Only)
• Receiver Hysteresis For Improved Noise Immunity
• Guaranteed Minimum Data Rate . . . . . . . . . . . . . 250kbps
• Wide Power Supply Range . . . . . . . 3V to +5.5V
• Low Supply Current in Power-down State . . . . . . 1 μ A
• Pb-Free Available (RoHS Compliant)
Applications
• Any System Requiring RS-232 Communication Ports
- Battery Powered, Hand-Held, and Portable Equipment
- Laptop Computers, Notebooks, Palmtops
- Modems, Printers and other Peripherals
- Digital Cameras
- Cellular/Mobile Phones