- 您现在的位置：买卖IC网 > PDF目录15504 > MIC2169YMM (Micrel Inc)IC REG CTRLR BUCK PWM VM 10-MSOP PDF资料下载
参数资料
| 型号： | MIC2169YMM |
| 厂商： | Micrel Inc |
| 文件页数： | 6/15页 |
| 文件大小： | 0K |
| 描述： | IC REG CTRLR BUCK PWM VM 10-MSOP |
| 标准包装： | 100 |
| PWM 型： | 电压模式 |
| 输出数： | 1 |
| 频率 - 最大： | 550kHz |
| 占空比： | 92% |
| 电源电压： | 3 V ~ 14.5 V |
| 降压： | 是 |
| 升压： | 无 |
| 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： | 10-TFSOP，10-MSOP（0.118"，3.00mm 宽） |
| 包装： | 管件 |
| 产品目录页面： | 1092 (CN2011-ZH PDF) |
| 其它名称： | 576-1710-5 MIC2169YMM-ND |
MIC2169
Functional Diagram
C IN
RCS
Micrel
V IN
CS
V DD
5V
5V LDO
V DD
5V
Current Limit
Comparator
High-Side
Driver
HSD
Q1
D1
Current Limit
BOOST
Bandgap
Reference
0.8V
BG Valid
Reference
SW
2 Ω
RSW
C BST
L1
V OUT
5V
Soft-Start &
Clamp &
Startup
Current
Driver
Logic
5V
1.4 Ω
1000pF
C OUT
Digital Delay
Counter
Ramp
Clock
PWM
Comparator
Low-Side
Driver
LSD
Q2
Enable
Error
Loop
0.8V
Error
Amp
V REF +3%
V REF 3%
Hys
Comparator
FB
R3
R2
MIC2169
COMP
GND
C2
C1
R1
MIC2169 Block Diagram
Functional Description
The MIC2169 is a voltage mode, synchronous step-down
switching regulator controller designed for high power without
the use of an external sense resistor. It includes an internal
soft-start function (which reduces the power supply input
surge current at start-up by controlling the output voltage rise
time), a PWM generator, a reference voltage, two MOSFET
drivers, and short-circuit current limiting circuitry to form a
complete 500kHz switching regulator.
Theory of Operation
The MIC2169 is a voltage mode step-down regulator. The
block diagram, above, illustrates the voltage control loop. The
output voltage variation due, to load or line changes, will be
sensed by the inverting input of the transconductance error
ampli ? er via the feedback resistors R3, and R2 and compared
to a reference voltage at the non-inverting input. This will cause
a small change in the DC voltage level at the output of the
error ampli ? er which is the input to the PWM comparator. The
other input to the comparator is a 5V triangular waveform. The
comparator generates a rectangular waveform whose width
t ON is equal to the time from the start of the clock cycle t 0 until
t 1 , the time the triangle crosses the output waveform of the
error ampli ? er. To illustrate the control loop, assume the output
voltage drops due to sudden load turn-on, this would cause
the inverting input of the error ampli ? er which is a divided
down version of V OUT to be slightly less than the reference
voltage. This causes the output voltage of the error ampli ? er
to go high. This will also increase the PWM comparator t ON
time of the top side MOSFET, causing the output voltage to
go up and bringing V OUT back in regulation.
Soft-Start
The COMP pin on the MIC2169 is used for the following two
functions:
1. External compensation to stabilize the voltage
control loop.
2. Soft-start.
For better understanding of the soft-start feature, assume V IN
= 12V. The COMP pin has an internal 6.5 μ A current source
that charges the external compensation capacitor. As soon as
this voltage rises to 180mV (t = Cap_COMP × 0.18V/8.5 μ A),
the MIC2169 allows the internal V DD linear regulator to power
up and as soon as it crosses the undervoltage lockout of 2.6V,
the chip’s internal oscillator starts switching. At this point, the
COMP pin current source increases to 40 μ A and an internal
11-bit counter starts counting. This takes approximately 2ms
to complete. During counting, the COMP voltage is clamped
at 0.65V. After this counting cycle, the COMP current source
is reduced to 8.5 μ A and the COMP pin voltage rises from
0.65V to 0.95V, the bottom edge of the saw-tooth oscillator.
This is the beginning of 0% duty cycle which increases slowly
causing the output voltage to rise slowly. The MIC2169 has
M9999-032409
6
March 2009
相关PDF资料 |
PDF描述 |
|---|---|
| SP6136ER1-L | IC REG CTRLR BUCK PWM VM 16-QFN |
| LTC3822EDD#PBF | IC REG CTRLR BUCK PWM CM 10-DFN |
| SP6133ER1-L | IC REG CTRLR BUCK PWM VM 16-QFN |
| MIC3809YMM | IC REG CTRLR ISO PWM CM 8-MSOP |
| MIC38C43YN | IC REG CTRLR BST FLYBK ISO 8-DIP |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MIC2169YMM TR | 功能描述:直流/直流开关调节器 Replaced by MIC2169AYMM TR (Lead Free) RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5 |
| MIC2171 | 制造商:MICREL 制造商全称:Micrel Semiconductor 功能描述:100kHz 2.5A Switching Regulator Preliminary Information |
| MIC2171_07 | 制造商:MICREL 制造商全称:Micrel Semiconductor 功能描述:100kHz 2.5A Switching Regulator |
| MIC2171BT | 功能描述:IC REG MULTI CONFIG 2.5A TO220-5 RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:20 系列:SIMPLE SWITCHER® 类型:降压（降压） 输出类型:固定 输出数:1 输出电压:12V 输入电压:4 V ~ 60 V PWM 型:电压模式 频率 - 开关:52kHz 电流 - 输出:1A 同步整流器:无 工作温度:-40°C ~ 125°C 安装类型:通孔 封装/外壳:16-DIP（0.300"，7.62mm） 包装:管件 供应商设备封装:16-DIP 其它名称:*LM2575HVN-12LM2575HVN-12 |
| MIC2171BTL3 | 制造商:RF Micro Devices Inc 功能描述: |
发布紧急采购，3分钟左右您将得到回复。