TEA1751T_LT_2
?NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 02 23 December 2009
15 of 29
NXP Semiconductors
TEA1751T; TEA1751LT
GreenChip III SMPS control IC
The driver output is latched in the logic, preventing multiple switch-on.
7.3.4 Demagnetization (FBAUX pin)
The system is always in quasi-resonant or discontinuous conduction mode. The internal
oscillator does not start a new primary stroke until the previous secondary stroke has
ended.
Demagnetization features a cycle-by-cycle output short circuit protection by immediately
lowering the frequency (longer off-time), thereby reducing the power level.
Demagnetization recognition is suppressed during the first t
sup(xfmr_ring)
time (2 約 typical).
This suppression may be necessary at low output voltages and at start-up and in
applications where the transformer has a large leakage inductance.
If pin FBAUX is open circuit or not connected, a fault condition is assumed and the
converter stops operating immediately. Operation restarts as soon as the fault condition is
removed.
7.3.5 Flyback control / time-out (FBCTRL pin)
The pin FBCTRL is connected to an internal voltage source of 3.5 V via an internal
resistor (typical resistance is 3 k?. As soon as the voltage on this pin is above
2.5 V (typical), this connection is disabled. Above 2.5 V the pin is biased with a small
current. When the voltage on this pin rises above 4.5 V (typical), a fault is assumed and
switching is inhibited. In the TEA1751 a restart will then be made, while in the TEA1751L
the protection will be latched.
When a small capacitor is connected to this pin, a time-out function can be created to
protect against an open control loop situation. (see Figure 11
and Figure 12
) The time-out
function can be disabled by connecting a resistor (100 k? to ground on the FBCTRL pin.
If the pin is shorted to ground, switching of the flyback controller is inhibited.
Fig 10. Peak current control of flyback part
V
sense(fb)max
(V)
V
FBCTRL
(V)
1.5 V
2.0 V
0.52 V
flyback
frequency
reduction
PFC off
FBSENSE peak voltage
014aaa16
PFC on
flyback
discontinuous
or QR
flyback
cycle skip
mode
1.4 V
0.13 V
发布紧急采购，3分钟左右您将得到回复。
相关PDF资料
TEA1761T/N2,118
IC CTRLR GREENCHIP SYNC 8-SOIC
TEA1762T/N2/DG,118
IC CTLR SMPS SW SO14
TEA1791T/N1,118
IC CTRLR GREENCHIP SYNC 8-SOIC
TMP03FS-REEL
IC SENSOR TEMP/SERIAL OC 8SOIC
TMP141AIDBVTG4
IC TEMP SENSOR DGTL OUT SOT23-6
TMP401AIDGKTG4
IC TEMP SENSOR DGTL OUT 8-MSOP
TPS2346PWRG4
IC HOT SWAP POWER MGR 24-TSSOP
TPS24711DGSR
IC CTRLR HOT SWAP 2.5-18V 10MSOP
相关代理商/技术参数
TEA1751T/N1518
制造商:NXP Semiconductors 功能描述:IC SMPS SOIC-16
TEA1752LT
制造商:PHILIPS 制造商全称:NXP Semiconductors 功能描述:GreenChip III SMPS control IC
TEA1752LT/N1,518
功能描述:DC/DC 开关控制器 IC CTLR SMPS SW MODE
RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK
TEA1752LT/N1/S1518
制造商:NXP 功能描述: 制造商:NXP Semiconductors 功能描述:
TEA1752T
制造商:未知厂家 制造商全称:未知厂家 功能描述:The TEA1752T and TEA1752LT combine a controller for Power Factor Correction (PFC) and a flyback controller.
TEA1752T/1791/DB/90W,598
制造商:NXP Semiconductors 功能描述:- Boxed Product (Development Kits) 制造商:NXP Semiconductors 功能描述:90W notebook adapter Ref
TEA1752T/N1,518
功能描述:DC/DC 开关控制器 IC CTLR SMPS SW MODE RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK
TEA1753
制造商:未知厂家 制造商全称:未知厂家 功能描述:The GreenChip III is the third generation of green Switched Mode Power Supply (SMPS) controller ICs.