- 您现在的位置：买卖IC网 > PDF目录15293 > LTC3814IFE-5#TRPBF (Linear Technology)IC REG CTRLR BST PWM CM 16-TSSOP PDF资料下载
参数资料
| 型号： | LTC3814IFE-5#TRPBF |
| 厂商： | Linear Technology |
| 文件页数： | 24/30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： | 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： | 16-TSSOP（0.173"，4.40mm）裸露焊盘 |
| 包装： | 带卷 (TR) |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页当前第24页第25页第26页第27页第28页第29页第30页
LTC3814-5
APPLICATIONS INFORMATION
about 3mA and driver current can be calculated by:
I GATE = f(Q G(TOP) + Q G(BOT) ), where Q G(TOP) and Q G(BOT)
Choose R1 = 133k and R2 = 20k. Now calculate timing
resistor R OFF :
are the gate charges of the top and bottom MOSFETs.
This loss is proportional to the supply voltage that
INTV CC is derived from, i.e., V IN , V OUT or an external
R OFF =
1 + 133k / 20k
250kHz ? 76pF
= 402.6k
D = 1 ?
= 0.5
supply connected to INTV CC .
4. C OUT loss. The output capacitor has the dif?cult job
of ?ltering the large RMS input current out of the synchro-
nous MOSFET. It must have a very low ESR to minimize
the AC I 2 R loss.
The duty cycle is:
12V
24V
and the maximum input current is:
Other losses, including C IN ESR loss, Schottky diode D1
conduction loss during dead time and inductor core loss
generally account for less than 2% additional loss. When
I IN(MAX) =
5A
1 ? 0.5
= 10A
making adjustments to improve ef?ciency, the input cur-
rent is the best indicator of changes in ef?ciency. If you
Choose the inductor for about 40% ripple current at the
maximum V IN :
make a change and the input current decreases, then the
ef?ciency has increased. If there is no change in input
current, then there is no change in ef?ciency.
L =
12V
250kHz ? 0.4 ? 10A
1
12V
24V
= 6 μ H
Checking Transient Response
The peak inductor current is:
+ (4A) = 12A
The regulator loop response can be checked by looking
at the load transient response. Switching regulators take
I L(PEAK) =
5A
1 ? 0.5
1
2
=
? 1 = 6.74
V SNS(NOM) =
= 128mV
several cycles to respond to a step in load current. When
load step occurs, V OUT immediately shifts by an amount
equal to ? I LOAD (ESR), where ESR is the effective series
resistance of C OUT . ? I LOAD also begins to charge or dis-
charge C OUT generating a feedback error signal used by the
regulator to return V OUT to its steady-state value. During
this recovery time, V OUT can be monitored for overshoot
or ringing that would indicate a stability problem.
Design Example
As a design example, take a supply with the following speci-
?cations: V IN = 12V ±20%, V OUT = 24V ± 5%, I OUT(MAX) =
5A, f = 250kHz. Since V IN can vary around the 12V nominal
value, connect a resistive divider from V IN to V OFF to keep
the frequency independent of V IN changes:
R1 12V
R2 1.55V
so, choose the CDEP147 5.9μH inductor with I SAT = 16.4A
at 100°C.
Next, choose the bottom MOSFET switch. Since the drain
of the MOSFET will see the full output voltage plus any
ringing, choose a 40V MOSFET to provide a margin of
safety. The Si7848DP has:
BV DSS = 40V
R DS(ON) = 9m Ω (max)/7.5m Ω (nom),
δ = 0.006/°C,
C MILLER = (14nC – 6nC)/20V = 400pF,
V GS(MILLER) = 3.5V,
θ JA = 20°C/W.
This yields a nominal sense voltage of:
1.7 ? 0.0075 Ω ? 5A
1 ? 0.5
38145fc
24
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 |
发布紧急采购，3分钟左右您将得到回复。