参数资料
型号: LTC3814IFE-5#TRPBF
厂商: Linear Technology
文件页数: 17/30页
文件大小: 0K
描述: IC REG CTRLR BST PWM CM 16-TSSOP
标准包装: 2,500
PWM 型: 电流模式
输出数: 1
频率 - 最大: 1MHz
占空比: 90%
电源电压: 4.5 V ~ 55 V
降压:
升压:
回扫:
反相:
倍增器:
除法器:
Cuk:
隔离:
工作温度: -40°C ~ 125°C
封装/外壳: 16-TSSOP(0.173",4.40mm)裸露焊盘
包装: 带卷 (TR)
LTC3814-5
APPLICATIONS INFORMATION
Input Capacitor Selection
The input capacitor of a boost converter is less critical
than the output capacitor, due to the fact that the inductor
is in series with the input and the input current waveform
is continuous (see Figure 8b). The input voltage source
impedance determines the size of the input capacitor,
which is typically in the range of 10μF to 100μF. A low
ESR capacitor is recommended though not as critical as
for the output capacitor.
The RMS input capacitor ripple current for a boost con-
verter is:
to approximately V OUT + INTV CC . The boost capacitor needs
to store about 100 times the gate charge required by the
top MOSFET. In most applications 0.1μF to 0.47μF, X5R
or X7R dielectric capacitor is adequate.
The reverse breakdown of the external diode, D B , must
be greater than V OUT . Another important consideration
for the external diode is the reverse recovery and reverse
leakage, either of which may cause excessive reverse
current to ?ow at full reverse voltage. If the reverse
current times reverse voltage exceeds the maximum al-
lowable power dissipation, the diode may be damaged.
For best results, use an ultrafast recovery diode such as
I RMS(CIN) = 0.3 ?
V IN(MIN)
L?f
? D MAX
the MMDL770T1.
IC/MOSFET Driver Supplies (INTV CC )
V OUT = 0.8V 1 +
Please note that the input capacitor can see a very high
surge current when a battery is suddenly connected to
the input of the converter and solid tantalum capacitors
can fail catastrophically under these conditions. Be sure
to specify surge-tested capacitors!
Output Voltage
The LTC3814-5 output voltage is set by a resistor divider
according to the following formula:
R FB1
R FB2
The external resistor divider is connected to the output as
shown in the Functional Diagram, allowing remote voltage
sensing. The resultant feedback signal is compared with
the internal precision 800mV voltage reference by the
error ampli?er. The internal reference has a guaranteed
tolerance of less than ±1 %. Tolerance of the feedback
resistors will add additional error to the output voltage.
0.1% to 1% resistors are recommended.
Top MOSFET Driver Supply (C B , D B )
An external bootstrap capacitor C B connected to the BOOST
pin supplies the gate drive voltage for the topside MOSFET.
This capacitor is charged through diode D B from INTV CC
when the switch node is low. When the top MOSFET turns
on, the switch node rises to V OUT and the BOOST pin rises
The LTC3814-5 drivers and the LTC3814-5 internal circuits
are supplied from the INTV CC pin (see Figure 1). These
pins have an operating range between 4.2V and 14V. If
the input voltage or another supply is not available in
this voltage range, two internal regulators are provided
to simplify the generation of this IC/driver supply voltage
as described in the next sections.
The N DRV Pin Regulator
The N DRV pin controls the gate of an external NMOS as
shown in Figure 9b and can be used to generate a regu-
lated 5.5V supply from V IN or V OUT . Since the NMOS is
external, it can be chosen with a BV DSS or power rating
as high as necessary to safely derive power from a high
voltage input or output voltage. In order to generate an
INTV CC supply that is always above the 4.2V UV threshold,
the supply connected to the drain must be greater than
4.2V + R NDRV ? 40μA + V T .
The EXTV CC Pin Regulator
A second low dropout regulator is available for voltages
≤ 15V. When a supply that is greater than 4.7V is con-
nected to the EXTV CC pin, the internal LDO will regulate
5.5V on INTV CC from the EXTV CC pin voltage and will also
disable the NDRV pin regulator. This regulator is disabled
when the IC is shut down, when INTV CC < 4.2V, or when
EXTV CC < 4.7V.
38145fc
17
相关PDF资料
PDF描述
H2AAT-10102-Y4-ND JUMPER-H1502TR/A2015Y/H1502TR 2"
LTC1625CS IC REG CTRLR BUCK PWM CM 16-SOIC
H2AAT-10102-W4-ND JUMPER-H1502TR/A2015W/H1502TR 2"
LTC3810IG#TRPBF IC REG CTRLR BUCK PWM CM 28-SSOP
H2AAT-10102-V4-ND JUMPER-H1502TR/A2015V/H1502TR 2"
相关代理商/技术参数
参数描述
LTC3816EFE#PBF 功能描述:IC DC-DC CTLR S-PHASE 38TSSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 专用型 系列:- 标准包装:2,000 系列:- 应用:控制器,DSP 输入电压:4.5 V ~ 25 V 输出数:2 输出电压:最低可调至 1.2V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:30-TFSOP(0.173",4.40mm 宽) 供应商设备封装:30-TSSOP 包装:带卷 (TR)
LTC3816EFE#TRPBF 功能描述:IC CONTROLLER S-PHASE 38TSSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 专用型 系列:- 标准包装:43 系列:- 应用:控制器,Intel VR11 输入电压:5 V ~ 12 V 输出数:1 输出电压:0.5 V ~ 1.6 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:48-VFQFN 裸露焊盘 供应商设备封装:48-QFN(7x7) 包装:管件
LTC3816EUHF#PBF 功能描述:IC DC-DC CTLR S-PHASE 32QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 专用型 系列:- 标准包装:2,000 系列:- 应用:控制器,DSP 输入电压:4.5 V ~ 25 V 输出数:2 输出电压:最低可调至 1.2V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:30-TFSOP(0.173",4.40mm 宽) 供应商设备封装:30-TSSOP 包装:带卷 (TR)
LTC3816EUHF#TRPBF 功能描述:IC CONTROLLER S-PHASE 32QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 专用型 系列:- 标准包装:43 系列:- 应用:控制器,Intel VR11 输入电压:5 V ~ 12 V 输出数:1 输出电压:0.5 V ~ 1.6 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:48-VFQFN 裸露焊盘 供应商设备封装:48-QFN(7x7) 包装:管件
LTC3816IFE#PBF 功能描述:IC CONTROLLER S-PHASE 38TSSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 专用型 系列:- 标准包装:43 系列:- 应用:控制器,Intel VR11 输入电压:5 V ~ 12 V 输出数:1 输出电压:0.5 V ~ 1.6 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:48-VFQFN 裸露焊盘 供应商设备封装:48-QFN(7x7) 包装:管件