In this post, We learn more about CM501.
Part number : CM501
Manufacturer : Richtek
Functions : LCD driver for Sharp LC-42SV50U.
Package information : QFN48 Type
The CM501 generates all the supply rails for thin-film transistor (TFT) liquid-crystal display (LCD) panels in TVs and Monitors. It includes boost and buck regulators, VGH and VGL charge pump regulators, gate pulse modulator (GPM) , HV LDO, voltage detector (XAO) and VCOM OP. The CM501 can support input voltage from 8V to 14V and is optimized for LCD TV panel and LCD monitor applications running directly from 12V supply. The boost and buck regulators feature internal power MOSFETs and high-frequency operation allowing the use of small inductors and capacitors, resulting in a compact solution. Both switching regulators use fixed-frequency, current-mode control architectures, providing fast loadtransient response and easy compensation. The VGH and VGL charge-pump regulators provide supply voltages for TFT gate driver. Both output voltages can be adjusted with external resistive voltage dividers.
1. 8V to 14V Supply Input Voltage Range
2. Current-Mode Boost Regulator
3. 20V 3.5A 0.1Ω Internal N-MOSFET
4. Programmable Over Current Protection Voltage
5. ±1% Accurate Output
6. Progremmable Soft-start
7. Under Voltage Protection
8. Short Circuit Protection
9. Over Temperature Protection
10. Power On Sequence Control
LP395Z Information is available here.
Part Number : LP395Z
Function : This is a kind of semiconductor, Ultra Reliable Power Transistor.
Manufacturer : National Semiconductor
Some text files in PDF file :
LP395 Ultra Reliable Power Transistor April 1998 LP395 Ultra Reliable Power Transistor General
The LP395 is a fast monolithic transistor with complete overload protection. This very high gain transistor has included on the chip, current limiting, power limiting, and thermal overload protection, making it difficult to destroy from almost any type of overload. Available in an epoxy TO-92 transistor package this device is guaranteed to deliver 100 mA. Thermal limiting at the chip level, a feature not available in discrete designs, provides comprehensive protection against overload. Excessive power dissipation or inadequate heat sinking causes the thermal limiting circuitry to turn off the device preventing excessive die temperature. The LP395 offers a significant increase in reliability while simplifying protection circuitry. It is especially attractive as a small incandescent lamp or solenoid driver because of its low drive requirements and blowout-proof design. The LP395 is easy to use and only a few precautions need be observed. Excessive collector to emitter voltage can destroy the LP395 as with any transistor. When the device is used as an emitter follower with a low source impedance, it is necessary to insert a 4.7 kΩ resistor in series with the base lead to prevent possible emitter follower oscillations. Also since it has good high frequency response, supply by-passing is recommended. Areas where the LP395 differs from a standard NPN transistor are in saturation voltage, leakage (quiescent) current and in base current. Since the internal protection circuitry requires voltage and current to function, the minimum voltage across the device in the on condition (saturated) is typically 1.6 Volts, while in the off condition the quiescent (leakage) current is typically 200 µA. Base current in this device flows out of the base lead, rather than into the base as is the case with conventional NPN transistors. Also the base can be driven positive up to 36 [ … ]
LP395Z PDF File