SD3321是一款高效稳定的高亮度 LED恒流驱动芯片，内置高精度比较器，固定关断时间控制电路，恒流驱动电路等，适合单个或多个大功率 LED 串并联使用。
      SD3321 采用固定关断时间的峰值电流控制方式，其工作频率最高可达 1MHz，可使外部电感和滤波电容体积减小，效率提高，节省 PCB 面积。在 EN 端加 PWM 信号，可调节 LED 灯的亮度。
      SD3321 通过调节外置电流检测电阻的阻值来设置流过 LED 灯的电流，从而设置 LED 灯的亮度，流过 LED 灯的电流可从几十毫安到 2.5A。YX6220可工作于-40℃~+85℃。

特点

v 宽输入电压范围： 2.5V~24V
v 高效率：可高达 90%
v 典型内部集成稳压源值： 3.5V
v 最大工作频率： 1MHz
v 芯片供电欠压保护： 2.5V
v 亮度可调： EN 端加 PWM 信号，低电平有效,可直接与 3 功能 5 功能芯片或 MCU 的输出连接
v 关断时间可调

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