参数资料
型号: NCP1031DR2
厂商: ON Semiconductor
文件页数: 14/19页
文件大小: 0K
描述: IC CTRLR PWM OTP OVD HV 8SOIC
产品变化通告: Product Discontinuation 27/Jun/2007
标准包装: 2,500
输出隔离: 任意一种
频率范围: 260kHz ~ 325kHz
输入电压: 8 V ~ 16 V
输出电压: 200V
功率(瓦特): 6W
工作温度: -40°C ~ 125°C
封装/外壳: 8-SOIC(0.154",3.90mm 宽)
供应商设备封装: 8-SOICN
包装: 带卷 (TR)
其它名称: NCP1031DR2OS
NCP1030, NCP1031
be limited by the EA sink current, typically 110 m A.
Optimum transient response is obtained if the compensation
is discharging, guaranteeing a maximum duty cycle of 75 %
as shown in Figure 35.
components allow COMP to swing across its operating
range in 1 cycle.
Line Under and Overvoltage Detector
C T Ramp
COMP
Enabled
C T Charge
Signal
The NCP103x incorporates individual line undervoltage
(UV) and overvoltage (OV) shutdown circuits. The UV and
OV thresholds are 2.5 V. A fault is present if the UV is below
2.5 V or if the OV voltage is above 2.5 V. The UV/OV
detectors incorporate 175 mV hysteresis to prevent noise
from triggering the shutdown circuits.
The UV/OV circuits can be biased using an external
resistor divider from the input line as shown in Figure 34.
The UV/OV pins should be bypassed using a capacitor to
prevent triggering the UV or OV circuits during normal
switching operation.
V in
R 1
+
R 2
+ V UV
V OV R 3
-- --
Figure 34. UV/OV Resistor Divider
from the Input Line
The resistor divider must be sized to enable the controller
Power Switch Max
Duty Cycle
75%
25 %
Figure 35. Maximum Duty Cycle vs COMP
Figure 18 shows the relationship between the operating
frequency and C T . If an UV fault is present, both I CT(C) and
I CT(D) are reduced by a factor of 7, thus reducing the
operating frequency by the same factor.
The oscillator can be synchronized to a higher frequency
by capacitively coupling a synchronization pulse into the C T
pin. In sync mode, the voltage on the C T pin needs to be
driven above 3.5 V to trigger the internal comparator and
complete the C T charging period. However, pulsing the C T
pin before it reaches 3.5 V will reduce the p--p amplitude of
the C T Ramp as shown in Figure 36.
3.0 V/3.5 V
Sync Pulse Comparator
Reset
T2 (f2)
3.5 V
once V in is within the required operating range. While a UV
or OV fault is present, switching is not allowed and the
COMP pin is effectively grounded.
C T
Ramp
T1 (f1)
T2 (f2)
C T Voltage
Range in Sync
Either of these comparators can be used for a different
function if UV or OV functions are not needed. For example,
the UV/OV detectors can be used to implement an enable or
3.0 V
Free Running
Mode
Sync Mode
disable function. If positive logic is used, the enable signal
is applied to the UV pin while the OV pin is grounded. If
negative logic is used, the disable signal is applied to the OV
pin while biasing the UV pin from V CC using a resistor
divider.
Oscillator
Figure 36. External Frequency Synchronization
Waveforms
The oscillator frequency should be set no more that 25%
below the target sync frequency to maintain an adequate
voltage range and provide good noise immunity. A possible
circuit to synchronize the oscillator is shown in Figure 37.
The oscillator is optimized for operation up to 1 MHz and
its frequency is set by the external timing capacitor (C T )
connected to the C T pin. The oscillator has two modes of
operation, free running and synchronized (sync). While in
free running mode, an internal current source sequentially
charges and discharges C T generating a voltage ramp
between 3.0 V and 3.5 V. Under normal operating
conditions, the charge (I CT(C) ) and discharge (I CT(D) )
currents are typically 215 m A and 645 m A, respectively. The
5V
R1
C1
C T
R2
C T
2
charge:discharge current ratio of 1:3 discharges C T in 25 %
of the total period. The Power Switch is disabled while C T
Figure 37. External Frequency Synchronization
Circuit.
http://onsemi.com
14
相关PDF资料
PDF描述
RCM10DRMH-S288 CONN EDGECARD 20POS .156 EXTEND
VI-2T0-CY-F2 CONVERTER MOD DC/DC 5V 50W
TAJS334K020RNJ CAP TANT 0.33UF 20V 10% 1206
LC51024VG-10F676C IC XPLD 1024MC 10NS 676FPBGA
VI-2T0-CY-F1 CONVERTER MOD DC/DC 5V 50W
相关代理商/技术参数
参数描述
NCP1031DR2G 功能描述:直流/直流开关转换器 Bias Regulator w/On Chip Power 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
NCP1031MNTXG 功能描述:电流型 PWM 控制器 ANA BIAS REGLTR CNTR RoHS:否 制造商:Texas Instruments 开关频率:27 KHz 上升时间: 下降时间: 工作电源电压:6 V to 15 V 工作电源电流:1.5 mA 输出端数量:1 最大工作温度:+ 105 C 安装风格:SMD/SMT 封装 / 箱体:TSSOP-14
NCP1031POEEVB 功能描述:电源管理IC开发工具 EVAL BRD REGULATOR CONTROLLER RoHS:否 制造商:Maxim Integrated 产品:Evaluation Kits 类型:Battery Management 工具用于评估:MAX17710GB 输入电压: 输出电压:1.8 V
NCP1034 制造商:ONSEMI 制造商全称:ON Semiconductor 功能描述:100V Synchronous PWM Buck Controller
NCP1034BCK5VGEVB 功能描述:电源管理IC开发工具 48/5V 5A SYNC BCK RoHS:否 制造商:Maxim Integrated 产品:Evaluation Kits 类型:Battery Management 工具用于评估:MAX17710GB 输入电压: 输出电压:1.8 V