參數(shù)資料
型號(hào): RT9202B
廠商: Richtek Technology Corporation
英文描述: Single Synchronous Buck PWM DC-DC Controller
中文描述: 單同步降壓PWM DC - DC控制器
文件頁(yè)數(shù): 11/14頁(yè)
文件大?。?/td> 209K
代理商: RT9202B
RT9202B
11
DS9202B-03 March 2007
www.richtek.com
V
OUT
Inductor
3.3V
2.5V
1.5V
2
μ
H
100mV
62mV
40mV
5
μ
H
40mV
25mV
16mV
2
μ
H
110mV
68mV
43mV
5
μ
H
44mV
28mV
18mV
2
μ
H
93mV
58mV
37mV
5
μ
H
37mV
23mV
15mV
1000
μ
F (ESR=53m
)
1500
μ
F (ESR=33m
)
3000
μ
F (ESR=21m
)
*Refer to Sanyo low ESR series (CE, DX, PX.....)
Table 1
The suggested L and C are as follows:
2
μ
H with
1500
μ
F C
OUT
5
μ
H with
1000
μ
F C
OUT
Figure 5
Input / Output Capacitor
High frequency/long life decoupling capacitors should be
placed as close to the power pins of the load as physically
possible. Be careful not to add inductance to the PCB
trace, as it could eliminate the performance from utilizing
these low inductance components. Consult with the
manufacturer of the load on specific decoupling
requirements.
The output capacitors are necessary for filtering output
and stabilizing the close loop (see the PWM loop stability).
For powering advanced, high-speed processors, it is
required to meet with the requirement of fast load
transient, high frequency capacitors with low ESR/ESL
capacitors are recommended.
Another concern is high ESR induced ripple may trigger
UV or OV protections.
PWM Loop Stability
The RT9202B is a voltage mode buck controller designed
for 5V step-down applications. The gain of error amplifier
is fixed at 35dB for simplified design.
The output amplitude of ramp oscillator is 1.75V, the loop
gain and loop pole/zero are calculated as follows :
DC loop gain G
A
=
LC filter pole P
O
=
Error Amp pole P
A
= 300kHz
ESR zero Z
O
=
The RT9202B Bode plot as shown Figure 6 is stable in
most of application conditions.
V
I
V
O
R
C
D
L
Q
C.C.M
T
ON
T
OFF
T
S
V
L
V
I
- V
O
- V
O
uQ
mI
L
I
L
= I
O
i
L
i
Q
I
Q
I
D
i
D
V
L
OUT
V
0.8
1.75
5
35dB
×
×
LC
2
1
p
ESRC
2
1
p
相關(guān)PDF資料
PDF描述
RT9202BGS Single Synchronous Buck PWM DC-DC Controller
RT9202BPS Single Synchronous Buck PWM DC-DC Controller
RT9202GS Single Synchronous Buck PWM DC-DC Controller
RT9202PS Single Synchronous Buck PWM DC-DC Controller
RT9203AGS Dual Regulators - Synchronous Buck PWM DC-DC and Linear Controller
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
RT9202BGS 制造商:RICHTEK 制造商全稱:Richtek Technology Corporation 功能描述:Single Synchronous Buck PWM DC-DC Controller
RT9202BPS 制造商:RICHTEK 制造商全稱:Richtek Technology Corporation 功能描述:Single Synchronous Buck PWM DC-DC Controller
RT9202CS 制造商:RICHTEK 制造商全稱:Richtek Technology Corporation 功能描述:SINGLE SYNCHRONOUS BUCK PWM DC-DC CONTROLLER
RT9202GS 制造商:Richtek Technology Corporation 功能描述:
RT9202PS 制造商:RICHTEK 制造商全稱:Richtek Technology Corporation 功能描述:Single Synchronous Buck PWM DC-DC Controller