- 您现在的位置：买卖IC网 > PDF目录1830 > LTC3536IMSE#TRPBF (Linear Technology)IC REG BUCK BST SYNC ADJ 12MSOP PDF资料下载
参数资料
| 型号： | LTC3536IMSE#TRPBF |
| 厂商： | Linear Technology |
| 文件页数： | 20/28页 |
| 文件大小： | 0K |
| 描述： | IC REG BUCK BST SYNC ADJ 12MSOP |
| 标准包装： | 2,500 |
| 类型： | 降压（降压），升压（升压） |
| 输出类型： | 可调式 |
| 输出数： | 1 |
| 输出电压： | 1.8 V ~ 5.5 V |
| 输入电压： | 1.8 V ~ 5.5 V |
| PWM 型： | 电压模式，混合 |
| 频率 - 开关： | 300kHz ~ 2MHz |
| 电流 - 输出： | 1A |
| 同步整流器： | 是 |
| 工作温度： | -40°C ~ 125°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 12-TSSOP （0.118"，3.00mm 宽）裸露焊盘 |
| 包装： | 带卷 (TR) |
| 供应商设备封装： | 12-MSOP，裸露焊盘 |
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页当前第20页第21页第22页第23页第24页第25页第26页第27页第28页
LTC3536
APPLICATIONS INFORMATION
? ? ( 2 π f C ) ( R TOP C FB ) ? ?
= 198pF ≈ 180pF
C FB
f Z = ? f C = ? ( ) = 5.4kHz
37.8kHz
R FB =
= 163k ? ≈ 162k ?
C POLE =
= 3.71pF ≈ 3.9pF
C FF =
= 34.9pF ≈ 33pF
occuratthesamefrequency,f Z ,andbothhigherorderpoles
(f POLE2 and f POLE3 ) occur at the common frequency, f P .
This is a good starting point for determining the compen-
sation network. However the Bode plot for the complete
loop should be checked overall operating conditions and
for variations in components values to ensure that suf-
ficient phase margin and gain margin exists in all cases.
A reasonable choice is to pick the frequency of the poles,
f P , to be about 50 times higher than the frequency of the
zeros, f Z , which provides a peak phase boost of approxi-
mately Φ MAX = 60° as was assumed previously. Next, the
phase boost must be centered so that the peak phase
occurs at the target crossover frequency. The frequency
of the maximum phase boost, f C , is the geometric mean
of the pole and zero:
f C = f P ? f Z = 50 ? f Z 2 = 7 ? f Z
Therefore, in order to center the phase boost given a factor
of 50 separation between the pole and zero frequencies,
the zeros should be located at one-seventh of the cross-
over frequency and the poles should be located at seven
times the crossover frequency as given by the following
equations:
1 1
7 7
f P = 7 ? f C = 7 ? ( 37.8kHz ) = 264.6kHz
This placement of the poles and zeros will yield a peak phase
boost of 60° that is centered at the crossover frequency,
f C . Next, in order to produce the desired target crossover
frequency, the gain of the compensation network at the
point of maximum phase boost, G CENTER , must be set to
+2dB. The gain of the compensated error amplifier at the
point of maximum phase gain is given by:
Assuming a multiple of 50 separation between the pole
frequencies and zero frequencies this can be simplified
to the following expression:
? 50 ?
G CENTER = 20 log ? ?
The first step in defining the compensation component
values is to pick a value for R TOP that provides an accept-
ably low quiescent current through the resistor divider.
A value of R TOP = 845k is a reasonable choice. Next, the
value of C FB can be found:
G CENTER = 2dB
50
2dB
2 π ? ( 37.8kHz ) ? 845k ? ? 10 20
The compensation poles can be set at 264.6kHz and the
zeros at 5.4kHz by using the expressions for the pole and
zero frequencies given in the previous section. Setting the
frequency of the first zero, f ZERO1 , to 5.4kHz results in the
following value for R FB :
1
2 π ? ( 180pF ) ? 5.4kHz
This leaves the free parameter, C POLE , to set the frequency
f POLE1 to the common pole frequency of 264.6kHz as given:
1
2 π ? ( 162k ? ) ? 264.6kHz
Next, C FF can be chosen to set the second zero, f ZERO2 , to
the common zero frequency of 5.4kHz.
1
2 π ? ( 845k ? ) ? 5.4kHz
2 π f P
? ( 2 π f ) 3 ( R TOP C FB ) ?
2 ?
R FF =
= 18.2k ?
G CENTER = 10log
? ?
? ?
? Z
Finally, the resistor value R FF can be chosen to place the
second pole at 264.6kHz:
1
2 π ? ( 33pF ) ? 264.6kHz
3536fa
20
相关PDF资料 |
PDF描述 |
|---|---|
| LTC3538EDCB#TRPBF | IC REG BUCK BOOST SYNC ADJ 8DFN |
| LTC3539EDCB-2#TRPBF | IC REG BOOST SYNC ADJ 2A 8DFN |
| LTC3542IDC#TRMPBF | IC REG BUCK SYNC ADJ 0.5A 6DFN |
| LTC3543EDCB#TRPBF | IC REG BUCK SYNC ADJ 0.6A 8DFN |
| LTC3544BEUD#TRPBF | IC REG BUCK SYNC ADJ QUAD 16QFN |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LTC3537 | 制造商:LINER 制造商全称:Linear Technology 功能描述:2.2 MHz, 600mA Synchronous Step-Up DC/DC Converter and 100mA LDO |
| LTC3537EUD#PBF | 功能描述:IC REG DL BST/LINEAR SYNC 16-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 + 切换式 系列:- 标准包装:2,500 系列:- 拓扑:降压（降压）同步（3），线性（LDO）（2） 功能:任何功能 输出数:5 频率 - 开关:300kHz 电压/电流 - 输出 1:控制器 电压/电流 - 输出 2:控制器 电压/电流 - 输出 3:控制器 带 LED 驱动器:无 带监控器:无 带序列发生器:是 电源电压:5.6 V ~ 24 V 工作温度:-40°C ~ 85°C 安装类型:* 封装/外壳:* 供应商设备封装:* 包装:* |
| LTC3537EUD#TRPBF | 功能描述:IC REG DL BST/LINEAR SYNC 16-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 + 切换式 系列:- 标准包装:2,500 系列:- 拓扑:降压（降压）同步（3），线性（LDO）（2） 功能:任何功能 输出数:5 频率 - 开关:300kHz 电压/电流 - 输出 1:控制器 电压/电流 - 输出 2:控制器 电压/电流 - 输出 3:控制器 带 LED 驱动器:无 带监控器:无 带序列发生器:是 电源电压:5.6 V ~ 24 V 工作温度:-40°C ~ 85°C 安装类型:* 封装/外壳:* 供应商设备封装:* 包装:* |
| LTC3537EUD-PBF | 制造商:LINER 制造商全称:Linear Technology 功能描述:2.2 MHz, 600mA Synchronous Step-Up DC/DC Converter and 100mA LDO |
| LTC3537EUD-TRPBF | 制造商:LINER 制造商全称:Linear Technology 功能描述:2.2 MHz, 600mA Synchronous Step-Up DC/DC Converter and 100mA LDO |
发布紧急采购，3分钟左右您将得到回复。