参数资料
型号: RH5RH652B-T2
厂商: RICOH COMPANY LTD
元件分类: 稳压器
英文描述: PWM STEP-UP DC/DC CONVERTER
中文描述: 0.05 A SWITCHING CONTROLLER, 100 kHz SWITCHING FREQ-MAX, PSSO3
封装: SOT-23, 3 PIN
文件页数: 13/29页
文件大小: 199K
代理商: RH5RH652B-T2
The above explanation is directed to the calculation in an ideal case where there is no energy loss caused by the
resistance in the external components and LxSW. In an actual case, the maximum output current will be 50
to 80% of the above calculated maximum output current. In particular, care must be taken because V
IN
is
decreased in an amount corresponding to the voltage drop caused by LxSW when IL is large or V
IN
is low.
Furthermore, it is required that with respect to V
OUT
, Vf of the diode (about 0.3V in the case of a Schottky type
diode) be taken into consideration.
12
RH5RH
Therefore it is necessary that the setting of the input/output conditions and the selection of peripheral compo-
nents should be made with ILmax taken into consideration.
Output Current in Continuous Conduction Mode
When the operation enters into the continuous conduction mode by increasing the I
OUT
, ILmin becomes equal
to Iconst (> 0), and this current always flows through the inductor. Therefore, V
IN
· Iconst is added to P
IN
in
Equation 5.
Thus, P
IN
=V
IN
· Iconst+(P
ON
+P
OFF
)/T=V
OUT
· I
OUT
=P
OUT
When the above Equation is solved for I
OUT
,
I
OUT
=V
IN
2
· tonc
2
/(2 · L· T · (V
OUT
–V
IN
))+V
IN
· Iconst/V
OUT
............................................Equation 8
The peak current which flows through L · LxTr· SD is
ILmax=V
IN
· ton/L+Iconst...................................................................................................Equation 9
From Equations 6 and 9, the larger the value of L, the smaller the load current at which the operation enters
into the continuous mode, and the smaller the difference between ILmax and ILmin, and the smaller the value of
ILmax.
Therefore, when the load current is the same, the larger the value of L, the easier the selection of peripheral
components with a small allowable current becomes, and the smaller the ripple of the peripheral components can
be made. In this case, however, it must be noted from Equation 6 that I
OUT
becomes small when the allowable cur-
rent of the inductor is small or when V
IN
is so small that the operation cannot enter into the continuous mode.
HINTS
相关PDF资料
PDF描述
RH5RH372B-T1 PWM STEP-UP DC/DC CONVERTER
RH5RH472B-T1 PWM STEP-UP DC/DC CONVERTER
RH5RH572B-T1 PWM STEP-UP DC/DC CONVERTER
RH5RH672B-T1 PWM STEP-UP DC/DC CONVERTER
RH5RH372B-T2 PWM STEP-UP DC/DC CONVERTER
相关代理商/技术参数
参数描述
RH5RH653B 制造商:未知厂家 制造商全称:未知厂家 功能描述:Analog IC
RH5RH653B-T1 制造商:RICOH 制造商全称:RICOH electronics devices division 功能描述:PWM STEP-UP DC/DC CONVERTER
RH5RH653B-T2 制造商:RICOH 制造商全称:RICOH electronics devices division 功能描述:PWM STEP-UP DC/DC CONVERTER
RH5RH661A 制造商:未知厂家 制造商全称:未知厂家 功能描述:Analog IC
RH5RH661A-T1 制造商:RICOH 制造商全称:RICOH electronics devices division 功能描述:PWM STEP-UP DC/DC CONVERTER