R1218数据手册集成电路（IC）的稳压器-DC-DC开关稳压器规格书PDF

描述 Description

The R1218 Series are CMOS-based PWM step-up DC/DC converters, which are optimized to drive white LEDs with constant current. R1218 includes an under-voltage lockout circuit (UVLO), over-voltage protection circuit (OVP). By simply using an inductor, a resistor, and a capacitor (, a diode) as external components, white LEDs can be driven with constant current efficiency. R1218Nxx1A for 2 to 4 lights contains an internal diode while R1218Nxx2A for 5 to 7 lights requires an external diode. The LED current can be determined by the value of current setting resistor. The brightness of the LEDs can be adjusted by applying a PWM signal to the CE or VFB pin.

特性 Features

• Input Voltage Range (Maximum Rating)：1.8 V to 5.5 V (6.5 V)；
• Supply Current： Typ. 500 µA；
• Standby Current：Typ. 0 µA；
Oscillator Frequency (PWM control)：1.2 MHz；
Maximum Duty Cycle：Typ. 91 to 92%；
Feedback Voltage：Typ. 0.2 V；
UVLO Threshold Voltage：Typ. 1.6 V (Hysteresis Typ. 0.1 V)；
Lx Current limit Protection：Typ. 700 mA；
Over Voltage Protection (OVP) Threshold：Typ. 9.5 V (R1218x021A),Typ. 14.0 V (R1218x031A),Typ. 18.5 V (R1218x041A),Typ. 23.0 V (R1218x052A),Typ. 27.5 V (R1218x062A),Typ. 31.5 V (R1218x072A)；
• LED dimming control：by external PWM signal (Frequency 200 Hz to 5 kHz) to CE pin,by feedback voltage and filtered PWM signal (high frequency)；
• Built-in Nch MOSFET and diode：R1218xxx1A: Built-in 400 mA, 1.5 Ω, 20 V Nch MOSFET and diode；
• R1218xxx2A: Built-in 400 mA, 1.5 Ω, 33 V Nch MOSFET；
• Package：SOT-23-6；

应用 Application

• White LED Backlight for portable equipment

简介

R1218属于集成电路（IC）的稳压器-DC-DC开关稳压器。由制造生产的R1218稳压器 - DC-DC 开关稳压器DC-DC 开关稳压器 PMIC（电源管理集成电路）产品族中的产品是元器件级设备，用于需要稳定 DC 输入电压和/或将其转换为不同幅度的输出电压的应用。这些器件与称为“控制器”PMIC 的类似产品的区别在于集成了主开关元件，设备提供的电力会通过该元件。