参数资料
型号: LTC3783IFE#TR
厂商: LINEAR TECHNOLOGY CORP
元件分类: 稳压器
英文描述: 1 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, PDSO16
封装: 4.40 MM, PLASTIC, TSSOP-16
文件页数: 3/24页
文件大小: 250K
代理商: LTC3783IFE#TR
LTC3783
11
3783fb
OPERATION
INTVCC Regulator Bypassing and Operation
An internal, P-channel low dropout voltage regulator pro-
duces the 7V supply which powers the gate drivers and
logic circuitry within the LTC3783 as shown in Figure 3.
The INTVCC regulator can supply up to 50mA and must be
bypassed to ground immediately adjacent to the IC pins
with a minimum of 4.7μF low ESR or ceramic capacitor.
Good bypassing is necessary to supply the high transient
currents required by the MOSFET gate driver.
For input voltages that don’t exceed 8V (the absolute
maximum rating for INTVCC is 9V), the internal low dropout
regulator in the LTC3783 is redundant and the INTVCC pin
can be shorted directly to the VIN pin. With the INTVCC
pin shorted to VIN, however, the divider that programs the
regulated INTVCCvoltagewilldraw15μAfromtheinputsup-
ply, even in shutdown mode. For applications that require
the lowest shutdown mode input supply current, do not
connect the INTVCC pin to VIN. Regardless of whether the
INTVCC pin is shorted to VIN or not, it is always necessary
to have the driver circuitry bypassed with a 4.7μF low ESR
ceramic capacitor to ground immediately adjacent to the
INTVCC and GND pins.
In an actual application, most of the IC supply current is
used to drive the gate capacitance of the power MOSFET.
As a result, high input voltage applications in which a
large power MOSFET is being driven at high frequencies
can cause the LTC3783 to exceed its maximum junction
temperature rating. The junction temperature can be
estimated using the following equations:
IQ(TOT) = IQ + f QG
PIC = VIN (IQ + f QG)
TJ = TA + PIC θJA
The total quiescent current IQ(TOT) consists of the static
supply current (IQ) and the current required to charge and
discharge the gate of the power MOSFET. The 16-lead FE
package has a thermal resistance of
θJA = 38°C/W and
the DHD package has an
θJA = 43°C/W
As an example, consider a power supply with VIN = 12V
and VOUT = 25V at IOUT = 1A. The switching frequency is
300kHz, and the maximum ambient temperature is 70°C.
The power MOSFET chosen is the Si7884DP, which has a
maximum RDS(ON) of 10mΩ (at room temperature) and
+
1.230V
R2
R1
P-CH
7V
DRIVER
GATE
CVCC
4.7μF
X5R
CIN
INPUT
SUPPLY
6V TO 36V
GND
PLACE AS CLOSE AS
POSSIBLE TO DEVICE PINS
M1
3783 F03
INTVCC
VIN
GND
LOGIC
6V-RATED
POWER
MOSFET
Figure 3. Bypassing the LDO Regulator and Gate Driver Supply
相关PDF资料
PDF描述
LTC3783IDHD#TR 1 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, PDSO16
LTC3783IFE 1 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, PDSO16
LTC3785IUF#PBF 3 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, PQCC24
LTC3785EUF 3 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, PQCC24
LTC3786IMSE#TRPBF SWITCHING CONTROLLER, 900 kHz SWITCHING FREQ-MAX, PDSO16
相关代理商/技术参数
参数描述
LTC3785EUF#PBF 功能描述:IC REG CTRLR BST PWM VM 24-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 特色产品:LM3753/54 Scalable 2-Phase Synchronous Buck Controllers 标准包装:1 系列:PowerWise® PWM 型:电压模式 输出数:1 频率 - 最大:1MHz 占空比:81% 电源电压:4.5 V ~ 18 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-5°C ~ 125°C 封装/外壳:32-WFQFN 裸露焊盘 包装:Digi-Reel® 产品目录页面:1303 (CN2011-ZH PDF) 其它名称:LM3754SQDKR
LTC3785EUF#TRPBF 功能描述:IC REG CTRLR BST PWM VM 24-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:500kHz 占空比:96% 电源电压:4 V ~ 36 V 降压:无 升压:是 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:24-WQFN 裸露焊盘 包装:带卷 (TR)
LTC3785EUF-1#PBF 功能描述:IC REG CTRLR BST PWM VM 24-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:500kHz 占空比:96% 电源电压:4 V ~ 36 V 降压:无 升压:是 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:24-WQFN 裸露焊盘 包装:带卷 (TR)
LTC3785EUF-1#TRPBF 功能描述:IC REG CTRLR BST PWM VM 24-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:4,500 系列:PowerWise® PWM 型:控制器 输出数:1 频率 - 最大:1MHz 占空比:95% 电源电压:2.8 V ~ 5.5 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:6-WDFN 裸露焊盘 包装:带卷 (TR) 配用:LM1771EVAL-ND - BOARD EVALUATION LM1771 其它名称:LM1771SSDX
LTC3785EUFPBF 制造商:Linear Technology 功能描述:10V Synch Buck-Boost Controller LTC3785