- 您現在的位置：買賣IC網 > Datasheet目錄46 > SC418ULTRT (Semtech)IC REG DL BUCK/LINEAR 20MLPQ Datasheet資料下載
參數資料
| 型號： | SC418ULTRT |
| 廠商： | Semtech |
| 文件頁數： | 17/30頁 |
| 文件大小： | 691K |
| 描述： | IC REG DL BUCK/LINEAR 20MLPQ |
| 產品培訓模塊： | Power Supplies 101 |
| 標準包裝： | 1 |
| 系列： | EcoSpeed® |
| 拓撲： | 降壓（降壓）（1），線性（LDO）（1） |
| 功能： | 任何功能 |
| 輸出數： | 2 |
| 頻率 - 開關： | 1MHz |
| 電壓/電流 - 輸出 1： | 控制器 |
| 電壓/電流 - 輸出 2： | 0.75 V ~ 5.25 V，200mA |
| 帶 LED 驅動器： | 無 |
| 帶監控器： | 無 |
| 帶序列發生器： | 無 |
| 電源電壓： | 3 V ~ 28 V |
| 工作溫度： | -40°C ~ 85°C |
| 安裝類型： | 表面貼裝 |
| 封裝/外殼： | 20-MLPQ |
| 供應商設備封裝： | 20-MLPQ（3x3） |
| 包裝： | 標準包裝 |
| 其它名稱： | SC418ULTRTDKR |
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頁第15頁第16頁當前第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
SC418
7
FB
threshold
High-side
Drive (DH)
Low-side
rive (DL)
V
OUT
drifts up to due to leakage
current flowing into C
OUT
DH and DL off
DL turns on when Smart
SAVE threshold is reached
mart Power Save
hreshold (550mV)
DL turns off when FB
Single DH on-time pulse
after DL turn-off
V
OUT
discharges via inductor
and low-side MOSFET
Normal DL pulse after DH
on-time pulse
Normal V
OUT
ripple
Figure 7 Smart Power-Save
SmartDrive
TM
For each DH pulse, the DH driver initially turns on the
high-side MOSFET at a slower speed, allowing a softer,
smooth turn-off of the low-side diode. Once the diode is
off and the LX voltage has risen 0.5V above PGND, the
SmartDrive circuit automatically drives the high-side
MOSFET on at a rapid rate. This technique reduces switch-
ing noise while maintaining high efficiency, reducing the
need for snubbers or series resistors in the gate drive.
Enable Input for Switching Regulator
The EN input is a logic level input. When EN is low
(grounded), the switching regulator is off and in its lowest
power state. When EN is low and VDDA is above the VDDA
UVLO threshold, the output of the switching regulator
soft-discharges into the VOUT pin through an internal
5& resistor. When EN is a logic high (>V) the switching
regulator is enabled.
The EN input has internal resistors 2M& pullup to
VDDA, and a M& pulldown to AGND. These resistors will
normally cause the EN voltage to be near the logic high
trip point as VDDA reaches the VDDA UVLO threshold.
To prevent undesired toggling of EN and erratic startup
performance, the EN pin should not be allowed to float as
open-circuit.
Note that the LDO enable pin (ENL) can also disable the
switching regulator through the V
IN
UVLO function. Refer
to the ENL Pin and V
IN
UVLO section.
Current Limit Protection
The SC48 features programmable current limiting, which
is accomplished using the RDS
(ON)
of the lower MOSFET for
current sensing. The current limit is set by R
ILIM
resistor
which connects from the ILIM pin to the drain of the low-
side MOSFET. When the low-side MOSFET is on, an internal
0糀 current flows from the ILIM pin and through the R
ILIM
resistor, creating a voltage drop across the resistor. While
the low-side MOSFET is on, the inductor current flows
through it and creates a voltage across the RDS
(ON)
. The
voltage across the MOSFET is negative with respect to
PGND. If this MOSFET voltage drop exceeds the voltage
across R
ILIM
, the voltage at the ILIM pin will be negative and
current limit will activate. The current limit then keeps the
low-side MOSFET on and prevents another high-side on-
time, until the current in the low-side MOSFET reduces
enough to bring the I
LIM
voltage up to zero. This method
regulates the inductor valley current at the level shown by
I
LIM
in Figure 8.
Time
I
PEAK
I
LOAD
I
LIM
Figure 8 Valley Current Limit
The current limit schematic with the R
ILIM
resistor is shown
in Figure 9.
Applications Information (continued)
相關PDF資料 |
PDF描述 |
|---|---|
| SC424MLTRT | IC REG DL BUCK/LINEAR 28MLPQ |
| SC4250LISTRT | IC HOT SWAP CTRLR 8-SOIC |
| SC427MLTRT | IC REG DL BUCK/LINEAR 32MLPQ |
| SE95D,112 | IC SENSOR TEMP 2.8-5.5V SOT96-1 |
| SE97BTP,547 | IC TEMP SENSOR DIMM 8HWSON |
相關代理商/技術參數 |
參數描述 |
|---|---|
| SC419 | 制造商:SEMTECH 制造商全稱:Semtech Corporation 功能描述:EcoSpeedTM DC-DC Converter with Integrated Boost Diode |
| SC419970CGCR2 | 制造商:Motorola Inc 功能描述: |
| SC419EVB | 制造商:SEMTECH 制造商全稱:Semtech Corporation 功能描述:EcoSpeedTM DC-DC Converter with Integrated Boost Diode |
| SC419ULTRT | 功能描述:IC REG CTRLR BUCK PWM 20-MLPQ RoHS:是 類別:集成電路 (IC) >> PMIC - 穩壓器 - DC DC 切換控制器 系列:EcoSpeed®, SmartDrive™ 特色產品:LM3753/54 Scalable 2-Phase Synchronous Buck Controllers 標準包裝:1 系列:PowerWise® PWM 型:電壓模式 輸出數:1 頻率 - 最大:1MHz 占空比:81% 電源電壓:4.5 V ~ 18 V 降壓:是 升壓:無 回掃:無 反相:無 倍增器:無 除法器:無 Cuk:無 隔離:無 工作溫度:-5°C ~ 125°C 封裝/外殼:32-WFQFN 裸露焊盤 包裝:Digi-Reel® 產品目錄頁面:1303 (CN2011-ZH PDF) 其它名稱:LM3754SQDKR |
| SC41E6 | 制造商:INFINEON 制造商全稱:Infineon Technologies AG 功能描述:SIEMENS ANNOUNCES A SUB-MICTON GENERATION OF CHANNELLESS GATE-ARRAYS BASED ON THE PROVEN MEGALOGIC PROCESS |
發布緊急采購，3分鐘左右您將得到回復。