参数资料
型号: NCP1599GEVB
厂商: ON Semiconductor
文件页数: 13/15页
文件大小: 0K
描述: BOARD EVALUATION NCP1599
设计资源: NCP1599GEVB BOM
NCP1599GEVB Schematic
NCP1599GEVB Gerber Files
标准包装: 1
主要目的: DC/DC,步降
输出及类型: 1,非隔离
输出电压: 最低可调至 0.8V
电流 - 输出: 3A
输入电压: 3 ~ 5.5 V
稳压器拓扑结构: 降压
频率 - 开关: 1MHz
板类型: 完全填充
已供物品:
已用 IC / 零件: NCP1599
其它名称: NCP1599GEVBOS
NCP1599
R GM ) R C
C C2 +
of the converter. A higher bandwidth generally corresponds
to faster response times and lower overshoots to load
transients. However, the bandwidth should not be much
higher than 1/10 the switching frequency. The NCP1599
operates with a 1.0 MHz switching frequency, so it is
recommended to choose a crossover frequency between
40 kHz ? 100 kHz. The schematic of the NCP1599
compensator is shown in Figure 2. The default design uses
Rc and C C1 to form a lag (Type 2) compensator. The C C2
capacitor can be added to form an additional pole that is
typically used to cancel out the ESR zero of the output
capacitor. Finally, if extra phase margin is needed, the C FF
capacitor can be added (this does not help at low output
voltages, see below). The strategy taken here for choosing
Rc and C C1 is to set the crossover frequency with Rc, and set
(eq. 17)
2 p f ESR R GM R C
A feed ? forward capacitor is recommended for most
designs. The large resistor value and the parasitic
capacitance of the FB Pin can cause a high frequency pole
that can reduce the overall system phase margin. By placing
a feed ? forward capacitor C FF , these effects can be
significantly reduced. C FF will provide a positive phase shift
(lead) that can be used to increase phase margin. However,
it is important to note that the effectiveness of C FF decreases
with output voltage. This is due to the fact that the frequency
of the zero f zff and pole f pff get closer together as the output
voltage is reduced.
The frequency of the feed ? forward zero and pole are:
R C + @ W
f Z ff +
+ f Z ff
the compensator zero with C C1 .
Using the selected target crossover frequency, fc, set Rc to:
2 p @ f C @ C out V out
(eq. 11)
Gm EA @ G CS V FB
f C = Crossover frequency in Hertz (50kHz ? 200kHz is
f p ff +
1
2 p R FB1 C ff
1 R FB1 ) R FB2
2 p R FB1 C ff R FB2
V out
V FB
(eq. 18)
(eq. 19)
f Z1 +
R C
2 p
C C1
v C C1 v
2 p R C f C
2 p f p1 R C
P HSON + I
R DS(on)HS
(eq. 20)
recommended).
The zero, due to the compensation capacitor (Cc1) and the
compensation resistor (Rc), is located at:
1
(eq. 12)
When fast transient responses are desired, f Z1 should be
placed as high as possible, however it should not be higher
than the selected crossover frequency fc. The guideline
proposed here is to choose C C1 such that f Z1 falls somewhere
between the power pole f P1 and 1 ? 2 decade before the
selected crossover frequency fc:
3.16 1
(eq. 13)
The compensation capacitor (Cc1) and the output resistor
of error amplifier R GM creates another pole of the system,
and it’s located at:
Power Dissipation
The NCP1599 is available in thermally enhanced 6 ? pin,
DFN package. When the die temperature reaches +185 ° C,
the NCP1599 shuts down (see the Thermal ? Overload
Protection section). The power dissipated in the device is the
sum of the power dissipated from supply current (PQ),
power dissipated due to switching the internal power
MOSFET (P SW ), and the power dissipated due to the RMS
current through the internal power MOSFET (PON). The
total power dissipated in the package must be limited so the
junction temperature does not exceed its absolute maximum
rating of +150 ° C at maximum ambient temperature.
Calculate the power lost in the NCP1599 using the following
equations:
1. High side MOSFET
The conduction loss in the top switch is:
2
RMS_HSFET
,
f p2 +
R GM
2 p
C C1
1
(eq. 14)
Where R GM = 66 ? 10 3 W .
In this compensation scheme, the pole created by C C2 is
Where:
I RMS_FET +
I out 2 )
D I PP
12
2
D
(eq. 21)
,
f p3 +
R R (eq. 15)
2 p @ C C2 @ R
C
GM
P HSSW +
used to cancel out the zero created by the ESR of the output
capacitor. This pole is located at:
1
C GM
) R
For the typical case, use C C2 if:
D I PP is the peak ? to ? peak inductor current ripple.
The power lost due to switching the internal power high side
MOSFET is:
V in @ I out @ t r ) t f @ f SW (eq. 22)
2
f ESR t
f S
2
(eq. 16)
t r and t f are the rise and fall times of the internal power
MOSFET measured at SW node.
http://onsemi.com
13
相关PDF资料
PDF描述
GCC20DCMI-S288 CONN EDGECARD 40POS .100 EXTEND
GEC18DREN-S13 CONN EDGECARD 36POS .100 EXTEND
A9AAT-1608F FLEX CABLE - AFE16T/AF16/AFE16T
GSC06DREH-S13 CONN EDGECARD 12POS .100 EXTEND
A9BAA-1006F FLEX CABLE - AFF10A/AF10/AFE10T
相关代理商/技术参数
参数描述
NCP1599MNTWG 功能描述:直流/直流开关转换器 SYNC BUCK CONTROLLER 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
NCP15WB333E03RC 制造商:Murata Manufacturing Co Ltd 功能描述:LEADED NTC THERMISTOR
NCP15WB333J03RC 功能描述:热敏电阻 - NTC 33K OHM 5% RoHS:否 制造商:EPCOS 电阻:10 kOhms 功率额定值:150 mW 容差:2 % 端接类型:Radial 系列:B57703M 工作温度范围:- 55 C to + 125 C
NCP15WB333K03RC 功能描述:热敏电阻 - NTC 33K OHM 10% RoHS:否 制造商:EPCOS 电阻:10 kOhms 功率额定值:150 mW 容差:2 % 端接类型:Radial 系列:B57703M 工作温度范围:- 55 C to + 125 C
NCP15WB473D03RC 功能描述:NTC THERMISTOR 47K OHM 0.5% 0402 制造商:murata electronics north america 系列:NCP15 包装:散装 零件状态:在售 25°C 时欧姆阻值:47k 电阻容差:±0.5% B 值容差:±0.5% B0/50:- B25/50:4050K B25/75:- B25/85:4108K B25/100:4131K 工作温度:-40°C ~ 125°C 功率 - 最大值:100mW 长度 - 引线:- 安装类型:表面贴装 封装/外壳:0402(1005 公制) 标准包装:10,000