參數(shù)資料
型號: NCP1216D65R2
廠商: ON SEMICONDUCTOR
元件分類: 穩(wěn)壓器
英文描述: PWM Current-Mode Controller for High-Power Universal Off-line Supplies; Package: SOIC-8 Narrow Body; No of Pins: 8; Container: Tape and Reel; Qty per Container: 2500
中文描述: 0.5 A SWITCHING CONTROLLER, 71.5 kHz SWITCHING FREQ-MAX, PDSO8
封裝: SOIC-8
文件頁數(shù): 2/18頁
文件大小: 232K
代理商: NCP1216D65R2
NCP1216, NCP1216A
http://onsemi.com
10
Dynamic SelfSupply
The DSS principle is based on the charge/discharge of the
VCC bulk capacitor from a low level up to a higher level. We
can easily describe the current source operation with a bunch
of simple logical equations:
POWERON: If VCC < VCCOFF then the Current Source
is ON, no output pulses
If VCC decreasing > VCCON then the Current Source is
OFF, output is pulsing
If VCC increasing < VCCOFF then the Current Source is
ON, output is pulsing
Typical values are: VCCOFF = 12.2 V, VCCON = 10 V
To better understand the operational principle, Figure 18
offers the necessary light:
10
30
50
70
90
Figure 18. The Charge/Discharge Cycle Over a
10
mF VCC Capacitor
VCCOFF = 12.2 V
VCCON = 10 V
Vripple = 2.2 V
ON, I = 8 mA
OFF, I = 0 mA
Output Pulse
The DSS behavior actually depends on the internal IC
consumption and the MOSFET’s gate charge Qg. If we
select a 600 V 10 A MOSFET featuring a 30 nC Qg, then we
can compute the resulting average consumption supported
by the DSS which is:
Itotal [ Fsw
Qg ) ICC1.
(eq. 1)
The total IC heat dissipation incurred by the DSS only is
given by:
Itotal
Vpin8.
(eq. 2)
Suppose that we select the NCP1216P065 with the above
MOSFET, the total current is
(30 n
65 k)
) 900 m + 2.9 mA.
(eq. 3)
Supplied from a 350 VDC rail (250 VAC), the heat
dissipated by the circuit would then be:
350 V
2.9 mA
+ 1W
(eq. 4)
As you can see, it exists a tradeoff where the dissipation
capability of the NCP1216 fixes the maximum Qg that the
circuit can drive, keeping its dissipation below a given
target. Please see the “Power Dissipation” section for a
complete design example and discover how a resistor can
help to heal the NCP1216 heat equation.
Application note AND8069/D details tricks to widen the
NCP1216 driving implementation, in particular for large Qg
MOSFETs. This document can be downloaded at
www.onsemi.com/pub/Collateral/AND8069D.PDF.
Ramp Compensation
Ramp compensation is a known mean to cure
subharmonic oscillations. These oscillations take place at
half the switching frequency and occur only during
Continuous Conduction Mode (CCM) with a dutycycle
greater than 50%. To lower the current loop gain, one usually
injects between 50% and 100% of the inductor downslope.
Figure 19 depicts how internally the ramp is generated:
CS
L.E.B
19 k
2.9V
0V
Figure 19. Inserting a Resistor in Series with the
Current Sense Information brings Ramp
Compensation
+
From Setpoint
Rsense
Rcomp
DCmax = 75°C
In the NCP1216, the ramp features a swing of 2.9 V with
a Duty cycle max at 75%. Over a 65 kHz frequency, it
corresponds to a
2.9
0.75
65 kHz
+ 251 mV ms ramp.
(eq. 5)
In our FLYBACK design, let’s suppose that our primary
inductance Lp is 350 mH, delivering 12 V with a Np : Ns
ratio of 1:0.1. The OFF time primary current slope is thus
given by:
Vout ) Vf
Lp
Np
Ns
+ 371 mA msor37 mV ms
(eq. 6)
when projected over an Rsense of 0.1 W, for instance. If we
select 75% of the downslope as the required amount of
ramp compensation, then we shall inject 27 mV/
ms. Our
internal compensation being of 251 mV/
ms, the divider ratio
(divratio) between Rcomp and the 19 kW is 0.107. A few lines
of algebra to determine Rcomp:
19 k
divratio
1
* divratio +
2.37 k
W
(eq. 7)
Frequency Jittering
Frequency jittering is a method used to soften the EMI
signature by spreading the energy in the vicinity of the main
switching component. NCP1216 offers a
$4% deviation of
相關(guān)PDF資料
PDF描述
NCP1216D133R2 PWM Current-Mode Controller for High-Power Universal Off-line Supplies; Package: SOIC-8 Narrow Body; No of Pins: 8; Container: Tape and Reel; Qty per Container: 2500
NCP1216P133G PWM Current-Mode Controller for High-Power Universal Off-line Supplies ; Package: PDIP (8 Minus Pin 7); No of Pins: 7; Container: Rail; Qty per Container: 1000
NCP1216P100G PWM Current-Mode Controller for High-Power Universal Off-line Supplies; Package: PDIP (8 Minus Pin 7); No of Pins: 7; Container: Rail; Qty per Container: 1000
NCP1216D65R2G PWM Current-Mode Controller for High-Power Universal Off-line Supplies ; Package: SOIC-8 Narrow Body; No of Pins: 8; Container: Tape and Reel; Qty per Container: 2500
NCP1216D133R2G PWM Current-Mode Controller for High-Power Universal Off-line Supplies ; Package: SOIC-8 Narrow Body; No of Pins: 8; Container: Tape and Reel; Qty per Container: 2500
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
NCP1216D65R2G 功能描述:電流型 PWM 控制器 Current Mode PWM RoHS:否 制造商:Texas Instruments 開關(guān)頻率:27 KHz 上升時間: 下降時間: 工作電源電壓:6 V to 15 V 工作電源電流:1.5 mA 輸出端數(shù)量:1 最大工作溫度:+ 105 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:TSSOP-14
NCP1216LEDGEVB 功能描述:電源管理IC開發(fā)工具 NON ISOLATED BUCK LED DRI RoHS:否 制造商:Maxim Integrated 產(chǎn)品:Evaluation Kits 類型:Battery Management 工具用于評估:MAX17710GB 輸入電壓: 輸出電壓:1.8 V
NCP1216P065 制造商:ONSEMI 制造商全稱:ON Semiconductor 功能描述:PWM Current-Mode Controller for High-Power Universal Off-Line Supplies
NCP1216P100 功能描述:電流型 PWM 控制器 Current Mode PWM RoHS:否 制造商:Texas Instruments 開關(guān)頻率:27 KHz 上升時間: 下降時間: 工作電源電壓:6 V to 15 V 工作電源電流:1.5 mA 輸出端數(shù)量:1 最大工作溫度:+ 105 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:TSSOP-14
NCP1216P100G 功能描述:電流型 PWM 控制器 Current Mode PWM RoHS:否 制造商:Texas Instruments 開關(guān)頻率:27 KHz 上升時間: 下降時間: 工作電源電壓:6 V to 15 V 工作電源電流:1.5 mA 輸出端數(shù)量:1 最大工作溫度:+ 105 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:TSSOP-14