参数资料
型号: LTC3814IFE-5#TRPBF
厂商: Linear Technology
文件页数: 21/30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
If breadboard measurement is not practical, mathemat-
ical software such as MATHCAD or MATLAB can be used
to generate plots from the transfer function given in
Equation 1. A SPICE simulation can also be used to gener-
ate approximate gain/phase curves. Plug the expected
capacitor, inductor and MOSFET values into the following
SPICE deck and generate an AC plot of V OUT / V ITH with gain
in dB and phase in degrees. Refer to your SPICE manual
for details of how to generate this plot.
*This ? le simulates a simpli ? ed model of
the 3814-5 for generating a v(out)/(vith) or
a v(out)/v(outin) bode plot
.param vout=24
.param vin=12
.param L=10u
.param cout=270u
.param esr=.018
.param rload=24
*
.param rdson=0.02
.param Vrng=1
.param vsnsmax={0.173*Vrng-0.026}
.param K={vsnsmax/rdson/1.2}
.param wz={1/esr/cout}
.param wp={2/rload/cout}
*
* Feedback Ampli ? er
rfb1 outin vfb 29k
rfb2 vfb 0 1k
eithx ithx 0 laplace {0.8-v(vfb)} =
{1/(1+s/1000)}
eith ith 0 value={limit(1e6*v(ithx),0,2.4)}
cc1 ith vfb 100p
cc2 ith x1 0.01p
rc x1 vfb 100k
*
* Modulator/Output Stage
eout out 0 laplace {v(ith)} =
{0.5*K*Rload*vin/vout *(1+s/wz)/(1+s/wp)
*(1-s*L/Rload*vout*vout/vin/vin)}
rload out 0 {rload}
*
vstim out outin dc=0 ac=10m; ac stimulus
.ac dec 100 10 10meg
.probe
.end
With the gain/phase plot in hand, a loop crossover fre-
quency can be chosen. Usually the curves look something
like Figure 10. Choose the crossover frequency about 25%
of the switching frequency for maximum bandwidth. Al-
though it may be tempting to go beyond f SW /4, remember
that signi?cant phase shift occurs at half the switching
frequency that isn’t modeled in the above H(s) equation
and PSPICE code. Note the gain (GAIN, in dB) and phase
(PHASE, in degrees) at this point. The desired feedback
ampli?er gain will be –GAIN to make the loop gain at 0dB
at this frequency. Now calculate the needed phase boost,
assuming 60° as a target phase margin:
BOOST = – (PHASE + 30°)
If the required BOOST is less than 60°, a Type 2 loop can
be used successfully, saving two external components.
BOOST values greater than 60° usually require Type 3
loops for satisfactory performance.
Finally, choose a convenient resistor value for R1 (10k
is usually a good value). Now calculate the remaining
values:
(K is a constant used in the calculations)
f = chosen crossover frequency
G = 10 (GAIN/20) (this converts GAIN in dB to G in
absolute gain)
38145fc
21
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