参数资料
型号: MCP1612EV
厂商: Microchip Technology
文件页数: 13/22页
文件大小: 0K
描述: BOARD EVAL FOR MCP1612
标准包装: 1
主要目的: DC/DC,步降
输出及类型: 1,非隔离
输出电压: 0.8V,1V,1.2V,1.4V,1.7V,2.4V 和 3.3V
电流 - 输出: 1A
输入电压: 2.7 ~ 5.5 V
稳压器拓扑结构: 降压
频率 - 开关: 1.4MHz
板类型: 完全填充
已供物品:
已用 IC / 零件: MCP1612
产品目录页面: 669 (CN2011-ZH PDF)
MCP1612
Solving for C:
5.2.6
COMPENSATION COMPONENTS
C = I C × -----------
Δ t
Δ V C
Where:
I C = peak-to-peak ripple current
Δ t = on-time of P-channel MOSFET
Δ V C = output ripple voltage
An internal transconductance error amplifier is used to
compensate the buck converter. An external resistor
(R C ) and capacitor (C C ), connected between COMP
and GND, are all that is needed to provide a high-
bandwidth loop.
Table 5-1 identifies values for R C and C C for standard
buck inductor (L) and output capacitor (C OUT ) values.
There will also be some ripple voltage caused by the
TABLE 5-1:
R C and C C VALUES
ESR of the capacitor. The ripple is defined as follows.
EQUATION 5-7:
V ESRRIPPLE = ESR × I C
L
3.3 μH
2.2 μH
C OUT
10.0 μF
4.7 μF
R C
25 k Ω
10 k Ω
C C
1000 pF
1000 pF
For this example:
5.3
Printed Circuit Board (PCB)
Layout
I C = 165 mA
C = 4.7 μF
Δ t = 260 ns
ESR = 8 m Ω
Δ V C = (260 ns x 165 mA)/4.7 μF
Δ V C = 9.13 mV
V ESRRIPPLE = 8 m Ω x 165 mA
V ESRRIPPLE = 1.32 mV
Δ V OUT = Δ V C + V ESRRIPPLE
Δ V OUT = 9.13 mV + 1.32 mV
Δ V OUT = 10.45 mV
The MCP1612 is capable of switching over 1A at
1.4 MHz. As with all high-frequency switching power
supplies, good PCB layout techniques are essential to
prevent noise generated by the switching power-train
from interfering with the sensing circuitry.
There are two ground pins (P GND and A GND ) on the
MCP1612 to separate the large-signal ground current
from the small-signal circuit ground. These two
grounds should be kept separate, only connecting near
the input bulk capacitor.
Care must also be taken to minimize the length and
loop area of the large signal connections. Components
connected to this loop consist of the input bulk
5.2.4
INPUT CAPACITOR
capacitor, V IN , P GND and L X pins of the MCP1612, the
buck inductor and the output filter capacitor.
For the buck topology, the input current is pulled from
the source and the input capacitor in pulses. The size
of the input capacitor will determine the amount of
current pulled from the source. For most applications,
a 10 μF ceramic capacitor connected between the
MCP1612’s V IN and P GND is recommended to filter the
current pulses. Less capacitance can be used for
applications that have low source impedance. The
ripple current rating for ceramic capacitors are typically
very high due to their low loss characteristics. Low-cost
electrolytic capacitors can be used, but their ripple
current rating should not be exceeded.
5.2.5
V CC INPUT
The V CC input is used to bias the internal MCP1612
circuitry. A 10 Ω resistor is recommended between the
unregulated inputs V IN and V CC , along with a 0.1 μF
capacitor to ground to help isolate the V CC pin from the
switching noise.
? 2005 Microchip Technology Inc.
DS21921B-page 13
相关PDF资料
PDF描述
YB15WCKG01-5F24-JB SWITCH PUSH SPDT 0.4VA 28V
MIC94072YC6 TR IC POWER SWITCH HI SIDE SC70-6
PV32H501A02B00 TRIMMER 500 OHM 0.5W TH
8Y-38.400MEEQ-T CRYSTAL 38.400 MHZ 10PF SMD
MCP1630DM-DDBS1 BOARD DEMO BOOST AUTO INPUT
相关代理商/技术参数
参数描述
MCP1612-I/MF 制造商:MICROCHIP 制造商全称:Microchip Technology 功能描述:Single 1A, 1.4 MHz Synchronous Buck Regulator
MCP1612-I/MS 制造商:MICROCHIP 制造商全称:Microchip Technology 功能描述:Single 1A, 1.4 MHz Synchronous Buck Regulator
MCP1612T 制造商:MICROCHIP 制造商全称:Microchip Technology 功能描述:Single 1A, 1.4 MHz Synchronous Buck Regulator
MCP1612T-120I/MF 功能描述:开关变换器、稳压器与控制器 1.4MHz 1A Synch-Buck RoHS:否 制造商:Texas Instruments 输出电压:1.2 V to 10 V 输出电流:300 mA 输出功率: 输入电压:3 V to 17 V 开关频率:1 MHz 工作温度范围: 安装风格:SMD/SMT 封装 / 箱体:WSON-8 封装:Reel
MCP1612T-120I/MS 功能描述:开关变换器、稳压器与控制器 1.4MHz 1A Synch-Buck RoHS:否 制造商:Texas Instruments 输出电压:1.2 V to 10 V 输出电流:300 mA 输出功率: 输入电压:3 V to 17 V 开关频率:1 MHz 工作温度范围: 安装风格:SMD/SMT 封装 / 箱体:WSON-8 封装:Reel