- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄98055 > PM6675 (STMICROELECTRONICS) SWITCHING CONTROLLER, QCC24 PDF資料下載
參數(shù)資料
| 型號： | PM6675 |
| 廠商： | STMICROELECTRONICS |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | SWITCHING CONTROLLER, QCC24 |
| 封裝： | 4 X 4 MM, VFQFPN-24 |
| 文件頁數(shù)： | 15/47頁 |
| 文件大小： | 650K |
| 代理商： | PM6675 |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁當前第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁第32頁第33頁第34頁第35頁第36頁第37頁第38頁第39頁第40頁第41頁第42頁第43頁第44頁第45頁第46頁第47頁
Obsolete
Product(s)
- Obsolete
Product(s)
Obsolete
Product(s)
- Obsolete
Product(s)
Device description
PM6675
22/47
6.1.3
Pulse-Skip and No-Audible Pulse-Skip Modes
High efficiency at light load conditions is achieved by PM6675 entering the Pulse-Skip Mode
(if enabled). When one of the two fixed output voltages is set, Pulse-Skip power saving is a
default feature. At light load conditions the zero-crossing comparator truncates the low-side
switch on-time as soon as the inductor current becomes negative; in this way the
comparator determines the On-Time duration instead of the output ripple (see Figure 9).
Figure 9.
Inductor current and output voltage at light load with Pulse-Skip
As a consequence, the output capacitor is left floating and its discharge depends solely on
the current drained from the load. When the output ripple on the pin COMP falls under the
reference, a new shot is triggered and the next cycle begins. The Pulse-Skip mode is
naturally obtained enabling the zero-crossing comparator and automatically takes part in the
C.O.T. algorithm when the inductor current is about half the ripple current amount, i.e.
migrating from continuous conduction mode (C.C.M.) to discontinuous conduction mode
(D.C.M.).
The output current threshold related to the transition between PWM Mode and Pulse-Skip
Mode can be approximately calculated as:
Equation 19
At higher loads, the inductor current never crosses the zero and the device works in pure
PWM mode with a switching frequency around the nominal value.
A physiological consequence of Pulse-Skip Mode is a more noisy and asynchronous (than
normal conditions) output, mainly due to very low load. If the Pulse-Skip is not compatible
with the application, the PM6675, when set in adjustable mode-of-operation, allows the user
to choose between forced-PWM and No-Audible Pulse-Skip alternative modes (see
for details).
Output
voltage
Inductor
current
Vreg
TON TOFF
TIDLE
t
ON
OUT
IN
LOAD
T
L
2
V
)
Skip
2
PWM
(
I
=
相關PDF資料 |
PDF描述 |
|---|---|
| PM6680ATR | 0.4 A DUAL SWITCHING CONTROLLER, 500 kHz SWITCHING FREQ-MAX, QCC32 |
| PM6680A | 0.4 A DUAL SWITCHING CONTROLLER, 500 kHz SWITCHING FREQ-MAX, QCC32 |
| PM6680TR | 0.4 A DUAL SWITCHING CONTROLLER, 500 kHz SWITCHING FREQ-MAX, QCC32 |
| PM6685TR | DUAL SWITCHING CONTROLLER, 500 kHz SWITCHING FREQ-MAX, QCC32 |
| PM6686 | SWITCHING CONTROLLER, QCC32 |
相關代理商/技術參數(shù) |
參數(shù)描述 |
|---|---|
| PM6675AS | 功能描述:DC/DC 開關控制器 DDR 2/3 Memory Pwr Cntrl RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風格: 封裝 / 箱體:CPAK |
| PM6675ASTR | 功能描述:低壓差控制器 - LDO Complete DDR2/3 Mem Pwr supply controllr RoHS:否 制造商:Micrel 最大輸入電壓:5.5 V 輸出電壓:Adjustable 輸出電流:10 mA 負載調節(jié): 輸出類型:Adjustable, Fixed 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風格:SMD/SMT 封裝 / 箱體:SOT-23-6 |
| PM6675ATR | 功能描述:低壓差控制器 - LDO High eff SD CNRL RoHS:否 制造商:Micrel 最大輸入電壓:5.5 V 輸出電壓:Adjustable 輸出電流:10 mA 負載調節(jié): 輸出類型:Adjustable, Fixed 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風格:SMD/SMT 封裝 / 箱體:SOT-23-6 |
| PM6675S | 功能描述:DC/DC 開關控制器 DDR 2/3 Memory Pwr Cntrl RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風格: 封裝 / 箱體:CPAK |
| PM6675STR | 功能描述:低壓差控制器 - LDO Complete DDR2/3 Mem Pwr supply controllr RoHS:否 制造商:Micrel 最大輸入電壓:5.5 V 輸出電壓:Adjustable 輸出電流:10 mA 負載調節(jié): 輸出類型:Adjustable, Fixed 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風格:SMD/SMT 封裝 / 箱體:SOT-23-6 |
發(fā)布緊急采購，3分鐘左右您將得到回復。