参数资料
型号: S-8520A28MC-AVN-T2
元件分类: 稳压器
英文描述: 0.05 A SWITCHING CONTROLLER, 216 kHz SWITCHING FREQ-MAX, PDSO5
封装: SOT-23, 5 PIN
文件页数: 16/43页
文件大小: 488K
代理商: S-8520A28MC-AVN-T2
STEP-DOWN, PWM CONTROL or PWM / PFM SWITCHABLE SWITCHING REGULATOR CONTROLLOR
Rev.7.5_00
S-8520 / 8521 Series
Seiko Instruments Inc.
23
On the other hand, a reactive current flows through RA and RB. This reactive current must be reduced to a
negligible value with respect to the load current in the actual use of the IC so that the efficiency characteristics
will not be degraded. This requires that the value of RA and RB be made sufficiently large.
However, too large a value (more than 1 M
) for the RA and RB would make the IC vulnerable to external noise.
Check the influence of this value on actual equipment.
There is a tradeoff between the voltage accuracy of the OUT and the reactive current. This should be taken
into consideration based on the requirements of the intended application.
Deviations in the absolute value of the internal resistances (R1 and R2) in the IC vary with the output voltage of
the S-8520 / 8521 Series, and are broadly classified as follows:
Table 10
Output voltage
Deviations in the absolute value of R1 and R2 in the IC
1.5 V to 2.0 V
5.16 M
to 28.9 M
2.1 V to 2.5 V
4.44 M
to 27.0 M
2.6 V to 3.3 V
3.60 M
to 23.3 M
3.4 V to 4.9 V
2.44 M
to 19.5 M
5.0 V to 6.0 V
2.45 M
to 15.6 M
When a value of R1
+R2 given by the equation indicated below is taken in calculating the voltage value of
the output OUT, a median voltage deviation will be obtained for the OUT.
R1
+R2=2÷(1÷maximum deviation in absolute value of R1 and R2+1÷minimum deviation in absolute value
of R1 and R2)
Moreover, add a capacitor (CC) in parallel to the external resistance (RA) in order to avoid output
oscillations and other types of instability. (Refer to Figure 14.)
Make sure that CC is larger than the value given by the following equation:
CC (F)
≥1÷(2×π×RA ()×7.5 kHz)
If a large CC value is selected, a longer soft start time than the one set up in the IC will be set.
SII is equipped with a tool that allows you to automatically calculate the necessary resistance values of
RA and RB from the required voltage accuracy of the OUT. SII will be pleased to assist its customers in
determining the RA and RB values. Should such assistance be desired, please inquire.
Moreover, SII also has ample information on which peripheral components are suitable for use with this
IC and data concerning the deviations in the IC's characteristics. We are ready to help our customers
with the design of application circuits. Please contact the SII Components Sales Dept.
*1.
// shows the combined resistance in parallel.
Caution The above connection diagram and constant will not guarantees successful operation.
Perform through evaluation using the actual application to set the constant.
相关PDF资料
PDF描述
S-8520D27MC-BVM-T2 0.05 A SWITCHING CONTROLLER, 75 kHz SWITCHING FREQ-MAX, PDSO5
S-88502F-T1 5 V FIXED POSITIVE REGULATOR, PDSO8
S-88502F-T2 5 V FIXED POSITIVE REGULATOR, PDSO8
S-93C66AFJ-TBP 256 X 16 MICROWIRE BUS SERIAL EEPROM, PDSO8
S-AV10L 135 MHz - 155 MHz RF/MICROWAVE NARROW BAND HIGH POWER AMPLIFIER
相关代理商/技术参数
参数描述
S-8520A28MC-AVNT2G 功能描述:DC/DC 开关控制器 2.8V Step-Down PWM 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-8520A29MC-ARO-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-8520A29MC-AVO-T2 功能描述:DC/DC 开关控制器 2.9V Step-Down PWM 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-8520A29MC-AVOT2G 功能描述:DC/DC 开关控制器 2.9V Step-Down PWM 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-8520A30MC-ARP-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