ME4078是一款具有恒流恒压充电模式的锂电池充 电管理芯片。可以对双节(8.4V/8.7V)和三节(12.6V) 锂电池进行快速高效地充电。其采用电流模式PWM降 压型开关控制结构，为锂电池快速充电提供了微型、简 单且高效的解决方案。 ME4078内置防倒灌功能，所以实际应用不需要输 入端接二极管防倒灌。
ME4078由外部Sense电阻设定高精度的充电电流，
内部由分压电阻和精准的参考电压将电池的浮充电压设 定在双节(8.4V/8.7V)和三节(12.6V)。同时具有高达1% 的精度。当输入电源去掉后，芯片会自动进入低电流休 眠模式，电池的漏电流低至8uA。当充电周圳结束后， 如果电压降到8.2V(双节)，12.2V(三节)后芯片将 自动重新对电池进行充电。芯片还有充电定时保护功能，
充电6小时后自动关断。
应用场合：充电设备 便携式笔记本电脑 手持设备
封装形式：8- pin ESOP8
The LY73XX series is a set of three-terminal, low power, high voltage regulators implemented in CMOS ogy. The series features extremely low quiescent cur-technol-rent which is typically 4uμA. They high as 12V. The device provides large current with aallow input voltages as significantly small dropout voltage.
The LY73XX consists of a high-precision voltage refer- ence, an error correction circuit, and a current limnited output driver. They are available with several fixed out-put voltages ranging from 1.8V to 5.0V. CMOS technol-ogy ensures low dropout voltage and low current consumption. Although designed primarily as fixed volt-age regulators, these devices can be used with external components to generate variable voltages and currents.
Features
UItra low quiescent current: 4μA (typ.)
High input voltage (up to 12V)
Output voltage:1.8V, 2.5V, 2.7V, 3.0V, 3.3V, 3.5V, 5.0V
Output voltage accuracy: tolerance +3%
Maximum output current: 250mA
Low dropout voltage
Low temperature coefficient
package：TO-92, SOT-89-3 SOT23-3
Application
Battery-powered equipment
Voltage regulator for microprocessor
Voltage regulator for L AN cards
Wireless Communication equipment
Audio/Video equipment
LY76XX serieslow-dropoutlinear voltage regulators with a built-in voltage reference module, error correction module and phase compensation module. LY76XX series are based on the CMOS process and allow high voltage input with low quiescent current. This series can deliver 100mA output current and allow an input voltage as high as 40V.This series has the function of internal feedback resistor setting from 2.1Vto 12V. The output accuracy is t 2%.
Features
High output accuracy:土2%
Input voltage: up to 40 V
Output voltage: 2.1V ~ 12V
Utralow quiescent current (Typ.=3μA) Output Current: lour= 100mA
(When VIN = 5.5V and Vout =3.3V)Low temperature cofficient
Ceramic capacitor can be used
Package: SOT89-3. T092、SOT23-3
Typical Application
Electronic weighbridge
SCM
Phones, cordless phones
Security Products
Water meters, power meters
