- 您现在的位置：买卖IC网 > PDF目录14403 > FAN2002MPX (Fairchild Semiconductor)IC REG BUCK SYNC ADJ 1A 6MLP PDF资料下载
参数资料
| 型号： | FAN2002MPX |
| 厂商： | Fairchild Semiconductor |
| 文件页数： | 7/11页 |
| 文件大小： | 0K |
| 描述： | IC REG BUCK SYNC ADJ 1A 6MLP |
| 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： | 0.8 V ~ 5.5 V |
| 输入电压： | 2.5 V ~ 5.5 V |
| PWM 型： | 电流模式 |
| 频率 - 开关： | 1.3MHz |
| 电流 - 输出： | 1A |
| 同步整流器： | 是 |
| 工作温度： | -40°C ~ 85°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 6-MLP |
| 包装： | 标准包装 |
| 供应商设备封装： | 6-MLP（3x3） |
| 产品目录页面： | 1214 (CN2011-ZH PDF) |
| 其它名称： | FAN2002MPXDKR |
Block Diagram
DIGITAL
EN
V IN
SOFT START
IS
PFM
UNDER-VOLTAGE
LOCKOUT
IS
CURRENT
SENSE
FB
ERROR
REF
COMP
AMP
COMP
LOGIC
CONTROL
MOSFET
DRIVER
SW
0.8V
GND
IS
OVER
VOLTAGE
COMP
OSC
SLOPE COMPENSATION
REF
FB
NEG.
LIMIT
NEG.
LIMIT
SENSE
COMP
GND
Figure 3. Block Diagram
Detailed Operation Description
The FAN2001/FAN2002 is a step-down converter operating in a
current-mode PFM/PWM architecture with a typical switching
frequency of 1.3MHz. At moderate to heavy loads, the converter
operates in pulse-width-modulation (PWM) mode. At light loads
the converter enters a power-save mode (PFM pulse skipping)
to keep the ef?ciency high.
PWM Mode
In PWM mode, the device operates at a ?xed frequency of
1.3MHz. At the beginning of each clock cycle, the P-channel
transistor is turned on. The inductor current ramps up and is
monitored via an internal circuit. The P-channel switch is turned
off when the sensed current causes the PWM comparator to trip
when the output voltage is in regulation or when the inductor
current reaches the current limit (set internally to typically
1500mA). After a minimum dead time the N-channel transistor
is turned on and the inductor current ramps down. As the clock
cycle is completed, the N-channel switch is turned off and the
next clock cycle starts.
PFM (Power Save) Mode
As the load current decreases and the inductor current reaches
negative value, the converter enters pulse-frequency-modula-
tion (PFM) mode. The transition point for the PFM mode is given
by the equation :
PFM mode the device operates with a variable frequency and
constant peak current, thus reducing the quiescent current to
minimum. Consequently, the high ef?ciency is maintained at
light loads. As soon as the output voltage falls below a thresh-
old, set at 0.8% above the nominal value, the P-channel transis-
tor is turned on and the inductor current ramps up. The P-
channel switch turns off and the N-channel turns on as the peak
inductor current is reached (typical 450mA).
The N-channel transistor is turned off before the inductor cur-
rent becomes negative. At this time the P-channel is switched
on again starting the next pulse. The converter continues these
pulses until the high threshold (typical 1.6% above nominal
value) is reached. A higher output voltage in PFM mode gives
additional headroom for the voltage drop during a load transient
from light to full load. The voltage overshoot during this load
transient is also minimized due to active regulation during turn
on of the N-channel recti?er switch. The device stays in sleep
mode until the output voltage falls below the low threshold. The
FAN2001/FAN2002 enters the PWM mode as soon as the out-
put voltage can no longer be regulated in PFM with constant
peak current.
100% Duty Cycle Operation
As the input voltage approaches the output voltage and the duty
cycle exceeds the typical 95%, the converter turns the P-chan-
nel transistor continuously on. In this mode the output voltage is
equal to the input voltage minus the voltage drop across the P-
1 – ( V OUT ? V IN )
× ------------------------------------------
I OUT = V OUT
2 × L × f
channel transistor:
V OUT = V IN – I LOAD × (R dsON + R L ), where
The typical output current when the device enters PFM mode is
150mA for input voltage of 3.6V and output voltage of 1.2V. In
R dsON = P-channel switch ON resistance
I LOAD = Output current
R L = Inductor DC resistance
FAN2001/FAN2002 Rev. 1.0.2
7
www.fairchildsemi.com
相关PDF资料 |
PDF描述 |
|---|---|
| LQW15AN3N9D00D | INDUCTOR |
| LQW15AN36NJ00D | INDUCTOR |
| RCM30DCMH-S288 | CONN EDGECARD 60POS .156 EXTEND |
| RCM30DCMD-S288 | CONN EDGECARD 60POS .156 EXTEND |
| LQW15AN30NJ00D | INDUCTOR |
相关代理商/技术参数 |
参数描述 |
|---|---|
| FAN2011 | 制造商:FAIRCHILD 制造商全称:Fairchild Semiconductor 功能描述:1.5A Low Voltage Current Mode Synchronous PWM Buck Regulator |
| FAN2011_06 | 制造商:FAIRCHILD 制造商全称:Fairchild Semiconductor 功能描述:1.5A Low Voltage Current Mode Synchronous PWM Buck Regulator |
| FAN2011_ACA3086B WAF | 制造商:Fairchild Semiconductor Corporation 功能描述: |
| FAN2011EMPX | 功能描述:直流/直流开关转换器 ANG FG 1.5a Syncr. Switcher RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT |
| FAN2011I | 制造商:FAIRCHILD 制造商全称:Fairchild Semiconductor 功能描述:1.5A Low Voltage Current Mode Synchronous PWM Buck Regulator |
发布紧急采购，3分钟左右您将得到回复。