R1224N SERIES
PWM/VFM step-down DC/DC Controller
NO.EA-096-080825
OUTLINE
The R1224N Series are CMOS-based PWM step-down DC/DC Converter controllers with low supply current.
Each of these ICs consists of an oscillator, a PWM control circuit, a reference voltage unit, an error amplifier, a
phase compensation circuit, a soft-start circuit, a protection circuit, a PWM/VFM alternative circuit, a chip enable
circuit, resistors for output voltage detect, and input voltage detect circuit. A low ripple, high efficiency step-down
DC/DC converter can be easily composed of this IC with only several external components, or a power-transistor,
an inductor, a diode and capacitors. Output Voltage is fixed or can be adjusted with external resistors (Adjustable
types are without PWM/VFM alternative circuit).
With a PWM/VFM alternative circuit, when the load current is small, the operation is automatically switching
into the VFM oscillator from PWM oscillator. Therefore, the efficiency at small load current is improved. Several
types of the R1224Nxxx, which are without a PWM/VFM alternative circuit, are also available.
If the term of maximum duty cycle keeps on a certain time, the embedded protection circuit works. The
protection circuit is Reset-type protection circuit, and it works to restart the operation with soft-start and repeat
this operation until maximum duty cycle condition is released. When the cause of large load current or something
else is removed, the operation is automatically released and returns to normal operation.
Further, built-in UVLO function works when the input voltage is equal or less than UVLO threshold, it makes
this IC be standby and suppresses the consumption current and avoid an unstable operation.
FEATURES
• Supply Current................................................................Typ. 20µA (R1224Nxx2E/F/M/L, R1224N102M)
Typ. 30µA (R1224Nxx2G, R1224N102G)
Typ. 40µA (R1224Nxx2H, R1224N102H)
• Standby Current..............................................................Typ. 0µA
• Input Voltage Range .......................................................2.3V~18.5V
• Output Voltage Range.....................................................1.2V to 6.0V (R1224Nxx2x)
1.0V to VIN (R1224N102x)
• Output Voltage Accuracy.................................................±2.0%
• Oscillator Frequency.......................................................Typ. 180kHz (R1224Nxx2L/M, R1224N102M)
Typ. 300kHz (R1224Nxx2E/G, R1224N102G)
Typ. 500kHz (R1224Nxx2F/H, R1224N102H)
• Efficiency.........................................................................Typ. 90%
• Low Temperature-Drift Coefficient of Output Voltage......Typ. ±100ppm/°C
• Package .......................................................................... SOT-23-5
• Built-in Soft-start Function............................................... Typ. 10ms
• Built-in Current Limit Circuit
APPLICATIONS
• Power source for hand-held communication equipment, cameras, video instruments such as VCRs,
camcorders.
• Power source for battery-powered equipment.
• Power source for household electrical appliances.
1
5秒后页面跳转
一文带你了解压敏电阻器在直流电路中的过压保护作用
可控硅触发板选型指南
蓝白可调电位器的原理与使用特点解析
网络滤波器、EMI滤波器与EMC滤波器：分类关系与功能详解
微信公众号
抖音公众号
浙公网安备 33010502006866号 浙ICP备10014259号-119
营业执照ICP证
技术参数
数据手册
如果您发现信息不准确，
