- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄383611 > MIC4722YML (MICREL INC) 3mm x 3mm 2.7MHz 3A PWM Buck Regulator PDF資料下載
參數(shù)資料
| 型號： | MIC4722YML |
| 廠商： | MICREL INC |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | 3mm x 3mm 2.7MHz 3A PWM Buck Regulator |
| 中文描述： | 11 A SWITCHING REGULATOR, 3000 kHz SWITCHING FREQ-MAX, DSO12 |
| 封裝： | 3 X 3 MM, LEAD FREE, MLF-12 |
| 文件頁數(shù)： | 10/20頁 |
| 文件大?。?/td> | 581K |
| 代理商： | MIC4722YML |
Micrel, Inc.
MIC4722
(where V
D
is the diode forward voltage);
(
)
L
September 2007
10
M9999-090507-B
V
V
D
OUT
+
The total off time can be calculated as;
2.7MHz
D
1
T
OFF
=
Figure 4. Off-Time
Discontinuous Operation
Discontinuous operation is when the inductor current
discharges to zero during the off cycle. Figure 5
demonstrates the switch voltage and inductor currents
during discontinuous operation.
Figure 5. Discontinuous Operation
When the inductor current (I
L
) has completely
discharged, the voltage on the switch node rings at the
frequency determined by the parasitic capacitance and
the inductor value. In Figure 5, it is drawn as a DC
voltage, but to see actual operation (with ringing) refer to
the functional characteristics.
Discontinuous mode of operation has the advantage
over full PWM in that at light loads, the MIC4722 will skip
pulses as nessasary, reducing gate drive losses,
drastically improving light load efficiency.
Efficiency Considerations
Calculating the efficiency is as simple as measuring
power out and dividing it by the power in;
100
P
P
Efficiency
IN
OUT
×
=
Where input power (P
IN
) is;
IN
I
IN
IN
V
P
×
=
and output power (P
OUT
) is calculated as;
OUT
OUT
V
OUT
P
I
×
=
The Efficiency of the MIC4722 is determined by several
factors.
Rdson (Internal P-channel Resistance)
Diode conduction losses
Inductor Conduction losses
Switching losses
Rdson losses are caused by the current flowing through
the high side P-channel MOSFET. The amount of power
loss can be approximated by;
D
I
R
P
2
OUT
DSON
SW
×
×
=
Where D is the duty cycle.
Since the MIC4722 uses an internal P-channel
MOSFET, Rdson losses are inversely proportional to
supply voltage. Higher supply voltage yields a higher
gate to source voltage, reducing the Rdson, reducing the
MOSFET conduction losses. A graph showing typical
Rdson vs input supply voltage can be found in the typical
characteristics section of this datasheet.
Diode conduction losses occur due to the forward
voltage drop (V
F
) and the output current. Diode power
losses can be approximated as follows;
(
)
D
1
I
V
P
OUT
F
D
×
×
=
For this reason, the Schottky diode is the rectifier of
choice. Using the lowest forward voltage drop will help
reduce diode conduction losses, and improve efficiency.
Duty cycle, or the ratio of output voltage to input voltage,
determines whether the dominant factor in conduction
losses will be the internal MOSFET or the Schottky
diode. Higher duty cycles place the power losses on the
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| MIC4807 | 80V 8-Channel Addressable Low-Side Driver |
| MIC4807BN | 80V 8-Channel Addressable Low-Side Driver |
| MIC4826 | Low Input Voltage, 160VPP Output Voltage, EL Driver |
| MIC4826BMM | Low Input Voltage, 160VPP Output Voltage, EL Driver |
| MIC4826YMM | Low Input Voltage, 160VPP Output Voltage, EL Driver |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| MIC4722YML TR | 功能描述:直流/直流開關(guān)調(diào)節(jié)器 3mm X 3mm 2.7MHz 3A PWM Buck Regulator RoHS:否 制造商:International Rectifier 最大輸入電壓:21 V 開關(guān)頻率:1.5 MHz 輸出電壓:0.5 V to 0.86 V 輸出電流:4 A 輸出端數(shù)量: 最大工作溫度: 安裝風格:SMD/SMT 封裝 / 箱體:PQFN 4 x 5 |
| MIC4722YML-TR | 功能描述:Buck Switching Regulator IC Positive Adjustable 1V 1 Output 3A 12-VFDFN Exposed Pad, 12-MLF? 制造商:microchip technology 系列:- 包裝:剪切帶（CT） 零件狀態(tài):停產(chǎn) 功能:降壓 輸出配置:正 拓撲:降壓 輸出類型:可調(diào)式 輸出數(shù):1 電壓 - 輸入（最小值）:2.7V 電壓 - 輸入（最大值）:5.5V 電壓 - 輸出（最小值/固定）:1V 電壓 - 輸出（最大值）:5.5V 電流 - 輸出:3A 頻率 - 開關(guān):2.7MHz 同步整流器:無 工作溫度:-40°C ~ 125°C （TJ） 安裝類型:表面貼裝 封裝/外殼:12-VFDFN 裸焊盤，12-MLF? 供應商器件封裝:12-MLF?（4x4） 標準包裝:1 |
| MIC4723 | 制造商:MICREL 制造商全稱:Micrel Semiconductor 功能描述:3A 2MHz Integrated Switch Buck Regulator |
| MIC4723_08 | 制造商:MICREL 制造商全稱:Micrel Semiconductor 功能描述:3A 2MHz Integrated Switch Buck Regulator |
| MIC4723YML | 制造商:Rochester Electronics LLC 功能描述: 制造商:RF Micro Devices Inc 功能描述: |
發(fā)布緊急采購，3分鐘左右您將得到回復。