参数资料
型号: MCP16321T-ADJE/NG
厂商: Microchip Technology
文件页数: 18/34页
文件大小: 0K
描述: IC REG BUCK SYNC ADJ 1A 16-VQFN
标准包装: 1
类型: 降压(降压)
输出类型: 可调式
输出数: 1
输出电压: 0.9 V ~ 5 V
输入电压: 6 V ~ 24 V
PWM 型: 电流模式
频率 - 开关: 1MHz
电流 - 输出: 1A
同步整流器:
工作温度: -40°C ~ 125°C
安装类型: 表面贴装
封装/外壳: 16-VFQFN 裸露焊盘
包装: 标准包装
供应商设备封装: 16-QFN(3x3)
其它名称: MCP16321T-ADJE/NGDKR
MCP16321/2
4.2.2
PEAK CURRENT MODE CONTROL
4.2.4
HIGH-SIDE DRIVE
The MCP16321/2 integrates a Peak Current Mode
Control architecture, resulting in superior AC regulation
while minimizing the number of voltage loop
compensation components, and their size, for
integration. Peak Current Mode Control takes a small
portion of the inductor current, replicates it and
compares this replicated current sense signal with the
output of the integrated error voltage. In practice, the
inductor current and the internal switch current are
equal during the switch-on time. By adding this peak
current sense to the system control, the step-down
power train system can be approximated by a 1 st order
system rather than a 2 nd order system. This reduces
the system complexity and increases its dynamic
performance.
For Pulse-Width Modulation (PWM) duty cycles that
exceed 50%, the control system can become bimodal,
where a wide pulse followed by a short pulse repeats
instead of the desired fixed pulse width. To prevent this
mode of operation, an internal compensating ramp is
summed into the current sense signal.
4.2.3 PULSE WIDTH MODULATION
(PWM)
The internal oscillator periodically starts the switching
period, which in the MCP16321/2’s case occurs every
1 μs or 1 MHz. With the high-side integrated
N-Channel MOSFET turned on, the inductor current
ramps up until the sum of the current sense and slope
compensation ramp exceeds the integrated error
amplifier output. Once this occurs, the high-side switch
turns off and the low-side switch turns on. The error
amplifier output slews up or down to increase or
decrease the inductor peak current feeding into the
output LC filter. If the regulated output voltage is lower
than its target, the inverting error amplifier output rises.
This results in an increase in the inductor current to
correct for errors in the output voltage. The fixed
frequency duty cycle is terminated when the sensed
inductor peak current, summed with the internal slope
compensation, exceeds the output voltage of the error
amplifier. The PWM latch is set by turning off the high-
side internal switch and preventing it from turning on
until the beginning of the next cycle.
DS22285A-page 18
The MCP16321/2 features an integrated high-side
N-Channel MOSFET for high efficiency step-down
power conversion. An N-Channel MOSFET is used for
its low resistance and size (instead of a P-Channel
MOSFET). The N-Channel MOSFET gate must be
driven above its source to fully turn on the device,
resulting in a gate-drive voltage above the input to turn
on the high-side N-Channel. The high-side N-Channel
source is connected to the inductor and boost cap or
switch node. When the high-side switch is off and the
low-side is on, the inductor current flows through the
low-side switch, providing a path to recharge the boost
cap from the boost voltage source. An internal boost-
blocking diode is used to prevent current flow from the
boost cap back into the output during the internal
switch-on time. Prior to startup, the boost cap has no
stored charge to drive the switch. An internal regulator
is used to “pre-charge” the boost cap. Once pre-
charged, the switch is turned on and the inductor
current flows. When the high-side switch turns off and
the low-side turns on, current freewheels through the
inductor and low-side switch, providing a path to
recharge the boost cap. When the duty cycle
approaches its maximum value, there is very little time
for the boost cap to be recharged due to the short
amount time that the low-side switch is on. Therefore,
when the maximum duty cycle approaches, the switch
node is forced off for 240 ns every 8 cycles to ensure
that the boost cap gets replenished.
? 2011 Microchip Technology Inc.
相关PDF资料
PDF描述
MCP16321T-250E/NG IC REG BUCK SYNC 2.5V 1A 16-VQFN
MCP16321T-180E/NG IC REG BUCK SYNC 1.8V 1A 16-VQFN
70F473AI CHOKE RF VARNISHED 4700UH 5%
B41043A4398M 3900UF 16V 16X31.5 SINGLE END
70F333AI CHOKE RF VARNISHED 3300UH 5%
相关代理商/技术参数
参数描述
MCP16321T-ADJNG 制造商:MICROCHIP 制造商全称:Microchip Technology 功能描述:24V Input, 1A/2A Output, High Efficiency Synchronous Buck Regulator with Power Good Indication
MCP16322 制造商:MICROCHIP 制造商全称:Microchip Technology 功能描述:24V Input, 1A/2A Output, High Efficiency Synchronous Buck Regulator with Power Good Indication
MCP16322T-150E 制造商:MICROCHIP 制造商全称:Microchip Technology 功能描述:24V Input, 1A/2A Output, High Efficiency Synchronous Buck Regulator with Power Good Indication
MCP16322T-150E/MG 制造商:Microchip Technology Inc 功能描述:2A SYNCHROUNS BUCK SWITCHER, 24VIN - Tape and Reel
MCP16322T-150E/NG 功能描述:开关变换器、稳压器与控制器 2A Synchrouns Buck 1.5V Switcher, 24Vin 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