- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄384892 > RT9238CS (Electronic Theatre Controls, Inc.) VRM 8.5 PWM AND TRIPLE LINEAR POWER SYSTEM CONTROLLER PDF資料下載
參數(shù)資料
| 型號： | RT9238CS |
| 廠商： | Electronic Theatre Controls, Inc. |
| 元件分類： | 基準(zhǔn)電壓源/電流源 |
| 英文描述： | VRM 8.5 PWM AND TRIPLE LINEAR POWER SYSTEM CONTROLLER |
| 中文描述： | VRM電源8.5脈寬調(diào)制和三線性電源系統(tǒng)控制器 |
| 文件頁數(shù)： | 17/24頁 |
| 文件大?。?/td> | 434K |
| 代理商： | RT9238CS |
Preliminary
RT9238
DS9238-01 July 2001
www.richtek-ic.com.tw
17
provide closed loop transfer function with 0 dB
crossing frequency and adequate phase margin. For
some suggestion LC combinations are L/C =
4
μ
H/6000
μ
F, 3uH/8000uF or 2
μ
H/12000
μ
F. Fig.9
shows an asymptotic plot of the DC-DC converter’s
gain vs. frequency.
Fig.8 Error Amplifier Compensation
Fig.9 PWM Bode Plot
Transient Response
Modern micro-processsor’s power supply request a
voltage droop at load transient response and a
loadlines at static state load changing as shown in
Fig.10, and Fig.11.
Fig.10 Transient Response
Fig.11 V
CORE
Load Line
Two things have to be completed at load transient
response, first is to sense the instantaneous load
current, second is real time to drop the V
CORE
voltage
based on the loadlines
.
A RT9238 internal trans-
conductance (Gm) amplifier sample the on-state drop
across the lower MOSFET per clock cycle, the
voltage drop is simply R
DS-ON X
inductor current IL. In
step-down DC-DC converter, the IL is relative to load
current. The transferred rate of the Gm amplifier is
1/3k, this mean the current output of Gm amplifier is
I
SENSE
= R
DS(ON)
x IL/3k.
Fig.12 shown the voltage droop tuning circuit, a
DACOUT buffer amplifier connect a RF resistor to the
non-inverting input of the PWM error amplifier, when
load transient happened, the feedback
I
SENSE
current
fitted to the non-inverting input of the PWM error
amplifier to drop the VCORE voltage. The drop
voltage is equal to
V
DROOP
= I
SENSE
x RF
Fig.12 Voltage Droop Tuning
+
_EA
Active Cap
10 100 1K 10K 100K 1M
100
80
60
40
20
0
-20
-40
-60
MODULATOR
GAIN
COMPENSATION
CLOSED
LOOP
GAIN
F
P1
F
ESR
F
LC
F
Z1
20logV
IN
V
P-P
I
O
V
CORE
Ripple
10 20 30 A
Volt
1.70
1.60
V
C
V
CORE
Maximum
V
CORE
Typical
V
CORE
Minimum
+
_
+
_
+
_
+
Gm
Control
Logic
RS
RS
COMP
VNI
RF
REFOUT
Reference Output
REF
LG
PHASE
UG
Rds-on
IM2
Sample Hold
Low Side Current Sense
Error Amp
Isense
DAC Buffer
IM1
VCORE
IL
V5V
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| RTE135 | Poly Switch PTC DEVICES |
| RTE190 | Poly Switch PTC DEVICES |
| RTL8019AS | Realtek Full-Duplex Ethernet Controller with Plug and Play Function (RealPNP) |
| RTL8168 | INTEGRATED GIGABIT ETHERNET CONTROLLER FOR PCI EXPRESS TM |
| RUE250U | Poly Switch PTC DEVICES |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| RT9241 | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Two-Phase DC/DC Controller for CPU Core Power Supply |
| RT9241A | 制造商:未知廠家 制造商全稱:未知廠家 功能描述: |
| RT9241AGS | 制造商:RICHTEK 制造商全稱:Richtek Technology Corporation 功能描述:Two-Phase DC/DC Controller for CPU Core Power Supply |
| RT9241APS | 制造商:RICHTEK 制造商全稱:Richtek Technology Corporation 功能描述:Two-Phase DC/DC Controller for CPU Core Power Supply |
| RT9241B | 制造商:未知廠家 制造商全稱:未知廠家 功能描述: |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。