- 您现在的位置：买卖IC网 > PDF目录192277 > S-8521C25MC-BTKT2G 0.05 A SWITCHING CONTROLLER, 72 kHz SWITCHING FREQ-MAX, PDSO5 PDF资料下载
参数资料
| 型号： | S-8521C25MC-BTKT2G |
| 元件分类： | 稳压器 |
| 英文描述： | 0.05 A SWITCHING CONTROLLER, 72 kHz SWITCHING FREQ-MAX, PDSO5 |
| 封装： | LEAD FREE, SOT-23, 5 PIN |
| 文件页数： | 10/44页 |
| 文件大小： | 511K |
| 代理商： | S-8521C25MC-BTKT2G |
第1页第2页第3页第4页第5页第6页第7页第8页第9页当前第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页第41页第42页第43页第44页
STEP-DOWN, PWM CONTROL or PWM / PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8520/8521 Series
Rev.9.0_00
Seiko Instruments Inc.
18
2.
Inductor
The inductance value (L value) has a strong influence on the maximum output current (IOUT) and efficiency (η).
The peak current (IPK) increases by decreasing L value and the stability of the circuit improves and IOUT increases. If
L value is decreased, the efficiency falls causing a decline in the current drive capacity for the switching transistor,
and IOUT decreases.
The loss of IPK by the switching transistor decreases by increasing L and the efficiency becomes the maximum at a
certain L value. Further increasing L value decreases the efficiency due to the loss of the direct current resistance
of the coil.
IOUT also decreases.
For the S-8520/8521 Series, increasing the inductance value, the output voltage may be unstable in some cases,
depending on the conditions of the input voltage, output voltage, and the load current. Perform sufficient evaluation
under the actual condition and decide an optimum inductance value.
The recommended inductances are 47
μH for A, B, C, D types and 22 μH for E, F types.
Be careful of the allowable inductor current when choosing an inductor. Exceeding the allowable current of the
inductor causes magnetic saturation, much lower efficiency and destruction of the IC chip due to a large current.
Choose an inductor so that IPK does not exceed the allowable current. IPK in continuous mode is calculated by the
following equation:
IPK = IOUT +
(VOUT + VF
*2 )
× (V
IN VOUT)
2
× f
osc
*1
× L × (V
IN + VF
*2)
*1.
fosc: Oscillation frequency
*2.
VF: Forward voltage of the diode
3.
Diode
Use an external diode that meets the following requirements :
Its forward voltage is low (Schottky barrier diode is recommended).
Its switching speed is high (50 ns max.).
Its reverse direction voltage is higher than V
IN.
Its current rating is higher than I
PK.
4.
Capacitors (CIN, COUT)
A capacitor for the input (CIN) improves efficiency by reducing power impedance and stabilizing the input current.
Select the CIN value according to impedance of the power supply to be used. Approximately 47 to 100 μF is
recommended for the capacitor depending on impedance of the power source and load current value.
For a capacitor for output (CL), select a large capacitance with low ESR (Equivalent Series Resistance) for
smoothing the ripple voltage. However, capacitor with extremely small ESR such as ceramic capacitor (about 0.3
Ω or less) may destabilize the output voltage, according to the conditions of input and output voltages. A
tantalum electrolyte capacitor is recommended. 47
μF to 100 μF is recommended for the capacitor.
相关PDF资料 |
PDF描述 |
|---|---|
| S-8520A31MC-AVQT2G | 0.05 A SWITCHING CONTROLLER, 207 kHz SWITCHING FREQ-MAX, PDSO5 |
| S-90N0113SMA-TFG | 1000 mA, 30 V, N-CHANNEL, Si, SMALL SIGNAL, MOSFET |
| S-93C46AFJ-TB-SG | 64 X 16 MICROWIRE BUS SERIAL EEPROM, PDSO8 |
| S-I6498#21 | 15A, 125VAC, FEMALE, MAINS POWER CONNECTOR, SOLDER |
| S-I6519#01 | 15A, 125VAC, FEMALE, MAINS POWER CONNECTOR, SOLDER |
相关代理商/技术参数 |
参数描述 |
|---|---|
| S-8521C25MC-BXK-T2 | 制造商:SII 制造商全称:Seiko Instruments Inc 功能描述:PWM CONTROL & PWM/PFM CONTROL STEP-DOWN SWITCHING REGULATOR-CONTROLLERS |
| S-8521C27MC-BTM-T2 | 功能描述:DC/DC 开关控制器 2.7V Step-Dn PWM/PFM RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK |
| S-8521C27MC-BTMT2G | 功能描述:DC/DC 开关控制器 2.7V Step-Dn PWM/PFM RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK |
| S-8521C27MC-BXM-T2 | 制造商:SII 制造商全称:Seiko Instruments Inc 功能描述:PWM CONTROL & PWM/PFM CONTROL STEP-DOWN SWITCHING REGULATOR-CONTROLLERS |
| S-8521C28MC-BTN-T2 | 功能描述:DC/DC 开关控制器 2.8V Step-Dn PWM/PFM RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK |
发布紧急采购，3分钟左右您将得到回复。