参数资料
| 型号： | FSQ110 |
| 厂商： | Fairchild Semiconductor |
| 文件页数： | 8/12页 |
| 文件大小： | 0K |
| 描述： | IC SWIT PWM GREEN CM OVP 8DIP |
| 标准包装： | 50 |
| 系列： | FPS™ |
| 输出隔离： | 隔离 |
| 频率范围： | 92kHz ~ 108kHz |
| 输入电压： | 9 V ~ 20 V |
| 输出电压： | 650V |
| 功率（瓦特）： | 17W |
| 工作温度： | -25°C ~ 85°C |
| 封装/外壳： | 8-DIP（0.300"，7.62mm） |
| 供应商设备封装： | 8-DIP |
| 包装： | 管件 |
| 其它名称： | FSQ110-ND FSQ110FS |
Functional Description
1. Startup: In previous generations of Fairchild Power
Switches (FPS?), the Vstr pin required an external
resistor to the DC input voltage line. In this generation,
the startup resistor is replaced by an internal high-
voltage current source and a switch that shuts off 10ms
after the supply voltage, V CC , goes above 12V. The
source turns back on if V CC drops below 8V.
V IN ,dc
I STR
4. Protection Circuits: The FPS has several protective
functions, such as Overload Protection (OLP), Over-
Voltage Protection (OVP), Under-Voltage Lockout
(UVLO), and Thermal Shutdown (TSD). Because these
protection circuits are fully integrated in the IC without
external components, reliability is improved without
increasing cost. Once a fault condition occurs, switching
is terminated and the SenseFET remains off. This
causes V CC to fall. When V CC reaches the UVLO stop
voltage, V STOP (typically 8V), the protection is reset and
V cc
V cc <8V
UVLO on
10ms after
V cc ≥ 12V
UVLO off
I CH
V str
J-FET
the internal high-voltage current source charges the V CC
capacitor via the Vstr pin. When V CC reaches the UVLO
start voltage, V START (typically 12V), the FPS resumes
normal operation. In this manner, the auto-restart can
alternately enable and disable the switching of the power
SenseFET until the fault condition is eliminated.
FSQ100 Rev. 1.00
Figure 13. High-Voltage Current Source
2. Feedback Control: The FSQ110 employs current-
mode control as shown in Figure 14. An opto-coupler
(such as the H11A817A) and shunt regulator (such as
the KA431) are typically used to implement the feedback
network. Comparing the feedback voltage with the
voltage across the R sense resistor of SenseFET, plus an
offset voltage, makes it possible to control the switching
duty cycle. When the shunt regulator reference pin
voltage exceeds the internal reference voltage of 2.5V,
the opto-coupler LED current increases, the feedback
voltage V FB is pulled down and thereby reduces the duty
cycle. This typically happens when the input voltage
increases or the output load decreases.
4.1 Overload Protection (OLP): Overload is defined as
the load current exceeding a pre-set level due to an
unexpected event. In this situation, the protection circuit
should be activated to protect the SMPS. However, even
when the SMPS is operating normally, the OLP circuit
can be activated during the load transition. To avoid this
undesired operation, the OLP circuit is designed to be
activated after a specified time to determine whether it is
a transient situation or a true overload situation. In
conjunction with the I PK current limit pin (if used), the
current mode feedback path limits the current in the
SenseFET when the maximum PWM duty cycle is
attained. If the output consumes more than this
maximum power, the output voltage (V O ) decreases
below nominal voltage. This reduces the current through
the opto-coupler LED, which also reduces the opto-
V O
431
FB
C FB
5 μ A 900 μ A
3 OSC
V FB
V CC V CC
+ D1 D2
V FB,in
2.5R
- R
Gate
driver
coupler transistor current, increasing the feedback
voltage (V FB ). If V FB exceeds 3V, the feedback input
diode is blocked and the 5μA current source (I DELAY )
starts to slowly charge C FB up to V CC . In this condition,
V FB increases until it reaches 6V, when the switching
operation is terminated, as shown in Figure 15. The
shutdown delay time is the time required to charge C FB
OLP
from 3V to 6V with 5μA current source.
FSQ110Rev. 1.00
V SD
V FB
FSQ110 Rev.00
Overload Protection
Figure 14. Pulse Width Modulation Circuit
3. Leading-Edge Blanking (LEB): When the internal
SenseFET is turned on, the primary-side capacitance
and secondary-side rectifier diode reverse recovery
typically cause a high-current spike through the
SenseFET. Excessive voltage across the R sense resistor
6V
3V
t 12 = C FB × (V(t 2 )-V(t 1 )) / I DELAY
leads to incorrect feedback operation in the current-
mode PWM control. To counter this effect, the FPS
employs a Leading-Edge Blanking (LEB) circuit. This
t 1
t 12 = C FB
V ( t 2 ) ? V ( t 1 )
I DELAY
;
t 2
I DELAY = 5 μ A , V ( t 1 ) = 3 V , V ( t 2 ) = 6 V
t
circuit inhibits the PWM comparator for a short time
(t LEB ) after the SenseFET is turned on.
? 2007 Fairchild Semiconductor Corporation
FSQ110 Rev. 1.0.0
8
Figure 15. Overload Protection (OLP)
www.fairchildsemi.com
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相关代理商/技术参数 |
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| FSQ210M | 功能描述:电源开关 IC - POE / LAN FPS RoHS:否 制造商:Fairchild Semiconductor 开关数量:Single 开关配置:SPST 开启电阻（最大值）:7.3 Ohms 串话: 带宽: 开启时间（最大值）:13 ns 关闭时间（最大值）:20 ns 切换电压（最大）: 工作电源电压:8 V to 26 V 最大工作温度:+ 125 C 安装风格:Through Hole 封装 / 箱体:TO-220F-6 |
| FSQ210MX | 制造商:Fairchild Semiconductor Corporation 功能描述:FPS |
| FSQ211 | 功能描述:电源开关 IC - 配电 SMPS Power Switch RoHS:否 制造商:Exar 输出端数量:1 开启电阻（最大值）:85 mOhms 开启时间（最大值）:400 us 关闭时间（最大值）:20 us 工作电源电压:3.2 V to 6.5 V 电源电流（最大值）: 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:SOT-23-5 |
| FSQ211L | 功能描述:电源开关 IC - 配电 SMPS Power Switch RoHS:否 制造商:Exar 输出端数量:1 开启电阻（最大值）:85 mOhms 开启时间（最大值）:400 us 关闭时间（最大值）:20 us 工作电源电压:3.2 V to 6.5 V 电源电流（最大值）: 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:SOT-23-5 |
| FSQ2W | 制造商:RFE 制造商全称:RFE international 功能描述:FUSIBLE RESISTORS FM, FKN, & FSQ Series: Fusible |
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