參數(shù)資料
型號: NCP1395APG
廠商: ON SEMICONDUCTOR
元件分類: 穩(wěn)壓器
英文描述: High Performance Resonant Mode Controller
中文描述: SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, PDIP16
封裝: LEAD FREE, PLASTIC, DIP-8
文件頁數(shù): 23/27頁
文件大?。?/td> 345K
代理商: NCP1395APG
NCP1395A/B
http://onsemi.com
23
In this figure, the internal OPAMP is used to perform a
kind of constant current operation (CC) by taking the lead
when the other voltage loop is gone (CV). Due to the ORing
capability on the FB pin, the OPAMP regulates in constant
current mode. When the output reaches a low level close to
a complete shortcircuit, the OPAMP output is maximum.
With a resistive divider on the slow fault, this condition can
be detected to trigger the delayed fault. If no OPAMP shall
be used, its input must be grounded.
Slow Input
On this circuit, the slow input goes to a comparator.
When this input exceeds 1.0 V typical, the current source
Itimer turns on, charging the external capacitor Ctimer. If
the fault duration is long enough, when Ctimer voltage
reaches the VtimerON level (4.0 V typical), then all pulses
are stopped. Itimer turns off and the capacitor slowly
discharges to ground via a resistor installed in parallel with
it. As a result, the designer can easily determine the time
during which the power supply stays locked by playing on
Rtimer. Now, when the timer capacitor voltage reaches
1.0 V typical (VtimerOFF), the comparator instructs the
internal logic to issues pulses as on a clean softstart
sequence (softstart is activated). Please note that the
discharge resistor cannot be lower than 4.0 V/Itimer,
otherwise the voltage on Ctimer will never reach the
turnoff voltage of 4.0 V.
In both cases, when the fault is validated, both outputs A
and B are internally pulled down to ground.
Fast Fault
FB
V
CC
Figure 49. A resistor can easily program the capacitor discharge time.
Figure 50. Skip cycle can be
implemented via two
resistors on the FB pin to the
fast fault input.
Fast Input
The fast input is not affected by a delayed action. As soon
as its voltage exceeds 1.0 V typical, all pulses are off and
maintained off as long as the fault is present. When the pin
is released, pulses come back without softstart for the
A version, with softstart for the B version.
Due to the low activation level of 1.0 V, this pin can
observe the feedback pin via a resistive divided and thus
implement skip cycle operation. The resonant converter
can be designed to lose regulation in light load conditions,
forcing the FB level to increase. When it reaches the
programmed level, it triggers the fast fault input and stops
pulses. Then V
out
slowly drops, the loop reacts by
decreasing the feedback level which, in turn, unlocks the
pulses: Vout goes up again and so on: we are in skip cycle
mode.
Startup Behavior
When the V
CC
voltage grows up, the internal current
consumption is kept to Istup, allowing to crank up the
converter via a resistor connected to the bulk capacitor.
When V
CC
reaches the V
CC
ON level, output A goes high
first and then output B. This sequence will always be the
same, whatever triggers the pulse delivery: fault, OFF to
ON etc
Pulsing the output A high first gives an
immediate charge of the bootstrap capacitor when an
integrated high voltage halfbridge driver is implemented
such as ON Semiconductor’s NCP5181. Then, the rest of
pulses follow, delivered at the highest switching value, set
by the resistor on pin 2. The softstart capacitor ensures a
smooth frequency decrease to either the programmed
minimum value (in case of fault) or to a value
corresponding to the operating point if the feedback loop
closes first. Figure 51 shows typical signals evolution at
power on.
相關PDF資料
PDF描述
NCP1395ADR2G High Performance Resonant Mode Controller
NCP1395BDR2G High Performance Resonant Mode Controller
NCP1395BPG High Performance Resonant Mode Controller
NCP1395A High Performance Resonant Mode Controller(高性能諧振模式控制器)
NCP1395B High Performance Resonant Mode Controller(高性能諧振模式控制器)
相關代理商/技術參數(shù)
參數(shù)描述
NCP1395B 制造商:ONSEMI 制造商全稱:ON Semiconductor 功能描述:High Performance Resonant Mode Controller
NCP1395BDR2G 功能描述:電壓模式 PWM 控制器 PWM CONTROLLER RoHS:否 制造商:Texas Instruments 輸出端數(shù)量:1 拓撲結構:Buck 輸出電壓:34 V 輸出電流: 開關頻率: 工作電源電壓:4.5 V to 5.5 V 電源電流:600 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 封裝 / 箱體:WSON-8 封裝:Reel
NCP1395BPG 功能描述:電壓模式 PWM 控制器 PWM CONTROLLER RoHS:否 制造商:Texas Instruments 輸出端數(shù)量:1 拓撲結構:Buck 輸出電壓:34 V 輸出電流: 開關頻率: 工作電源電壓:4.5 V to 5.5 V 電源電流:600 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 封裝 / 箱體:WSON-8 封裝:Reel
NCP1395D 制造商:ONSEMI 制造商全稱:ON Semiconductor 功能描述:High Performance Resonant Mode Controller
NCP1395LLCGEVB 功能描述:BOARD EVAL NCP1395 RoHS:是 類別:編程器,開發(fā)系統(tǒng) >> 評估板 - DC/DC 與 AC/DC(離線)SMPS 系列:* 產(chǎn)品培訓模塊:Obsolescence Mitigation Program 標準包裝:1 系列:True Shutdown™ 主要目的:DC/DC,步升 輸出及類型:1,非隔離 功率 - 輸出:- 輸出電壓:- 電流 - 輸出:1A 輸入電壓:2.5 V ~ 5.5 V 穩(wěn)壓器拓撲結構:升壓 頻率 - 開關:3MHz 板類型:完全填充 已供物品:板 已用 IC / 零件:MAX8969