参数资料
型号: HIP6018EVAL1
厂商: Intersil Corporation
元件分类: 基准电压源/电流源
英文描述: Advanced PWM and Dual Linear Power Control
中文描述: 先进的双PWM和线性功率控制
文件页数: 13/14页
文件大小: 133K
代理商: HIP6018EVAL1
2-236
Input Capacitor Selection
The important parameters for the bulk input capacitor are the
voltage rating and the RMS current rating. For reliable
operation, select the bulk capacitor with voltage and current
ratings above the maximum input voltage and largest RMS
current required by the circuit. The capacitor voltage rating
should be at least 1.25 times greater than the maximum
input voltage and a voltage rating of 1.5 times is a
conservative guideline.
Use a mix of input bypass capacitors to control the voltage
overshoot across the MOSFETs. Use ceramic capacitance
for the high frequency decoupling and bulk capacitors to
supply the RMS current. Small ceramic capacitors should be
placed very close to the upper MOSFET to suppress the
voltage induced in the parasitic circuit impedances.
For a through hole design, several electrolytic capacitors
(Panasonic HFQ series or Nichicon PL series or Sanyo
MV-GX or equivalent) may be needed. For surface mount
designs, solid tantalum capacitors can be used, but caution
must be exercised with regard to the capacitor surge current
rating. These capacitors must be capable of handling the
surge-current at power-up. The TPS series available from
AVX, and the 593D series from Sprague are both surge
current tested.
MOSFET Selection/Considerations
The HIP6018 requires 3 N-Channel power MOSFETs. Two
MOSFETs are used in the synchronous-rectified buck
topology of the PWM converter. The linear controller drives a
MOSFET as a pass transistor. These should be selected
based upon r
DS(ON)
, gate supply requirements, and thermal
management requirements.
PWM1 MOSFET Selection and Considerations
In high-current PWM applications, the MOSFET power
dissipation, package selection and heatsink are the dominant
design factors. The power dissipation includes two loss
components; conduction loss and switching loss. These
losses are distributed between the upper and lower
MOSFETs according to duty factor (see the equations below).
The conduction loss is the only component of power
dissipation for the lower MOSFET. Only the upper MOSFET
has switching losses, since the lower device turns on into near
zero voltage.
The equations below assume linear voltage-current
transitions and do not model power loss due to the reverse-
recovery of the lower MOSFET’s body diode. The gate-
charge losses are proportional to the switching frequency
(F
S
) and are dissipated by the HIP6018, thus not
contributing to the MOSFETs’ temperature rise. However,
large gate charge increases the switching interval, t
SW
which increases the upper MOSFET switching losses.
Ensure that both MOSFETs are within their maximum
junction temperature at high ambient temperature by
calculating the temperature rise according to package
thermal resistance specifications. A separate heatsink may
be necessary depending upon MOSFET power, package
type, ambient temperature and air flow.
The r
DS(ON)
is different for the two previous equations even
if the type device is used for both. This is because the gate
drive applied to the upper MOSFET is different than the
lower MOSFET. Figure 14 shows the gate drive where the
upper gate-to-source voltage is approximately V
CC
less the
input supply. For +5V main power and +12VDC for the bias,
the gate-to-source voltage of Q1 is 7V. The lower gate drive
voltage is +12VDC. A logic-level MOSFET is a good choice for
Q1 and a logic-level MOSFET can be used for Q2 if its
absolute gate-to-source voltage rating exceeds the maximum
voltage applied to V
CC
.
Rectifier CR1 is a clamp that catches the negative inductor
voltage swing during the dead time between the turn off of the
lower MOSFET and the turn on of the upper MOSFET. The
diode must be a Schottky type to prevent the lossy parasitic
MOSFET body diode from conducting. It is acceptable to omit
the diode and let the body diode of the lower MOSFET clamp
the negative inductor swing, but efficiency might drop one or
two percent as a result. The diode's rated reverse breakdown
voltage must be greater than twice the maximum input voltage.
Linear Controller MOSFET Selection
The main criteria for selection of MOSFET for the linear
regulator is package selection for efficient removal of heat.
The power dissipated in a linear regulator is:
Select a package and heatsink that maintains the junction
temperature below the maximum rating while operating at
the highest expected ambient temperature.
P
UPPER
I
------------------------------------------------------------
2
r
IN
×
V
×
I
----------------------------------------------------
V
×
t
×
F
S
×
+
=
P
LOWER
I
---------------------------------------------------------------------------------
2
r
IN
×
V
V
(
)
×
=
+12V
PGND
HIP6018
GND
LGATE
UGATE
PHASE
V
CC
+5V OR LESS
NOTE:
V
GS
V
CC
-5V
NOTE:
V
GS
V
CC
Q1
Q2
+
-
FIGURE 14. OUTPUT GATE DRIVERS
CR1
P
LINEAR
I
O
V
IN
V
OUT
(
)
×
=
HIP6018
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相关代理商/技术参数
参数描述
HIP6019 制造商:IRF 制造商全称:International Rectifier 功能描述:5-BIT PROGRAMMABLE SYNCHRONOUS BUCK, NON-SYNCHRONOUS,ADJUSTABLE LDO AND 200mA ON-BOARD LDO
HIP6019B 制造商:INTERSIL 制造商全称:Intersil Corporation 功能描述:Advanced Dual PWM and Dual Linear Power Control
HIP6019B_05 制造商:INTERSIL 制造商全称:Intersil Corporation 功能描述:Advanced Dual PWM and Dual Linear Power Control
HIP6019BBCB WAF 制造商:Harris Corporation 功能描述:
HIP6019BCB 功能描述:IC REG QD BCK/LINEAR 28-SOIC RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 + 切换式 系列:- 标准包装:2,500 系列:- 拓扑:降压(降压)同步(3),线性(LDO)(2) 功能:任何功能 输出数:5 频率 - 开关:300kHz 电压/电流 - 输出 1:控制器 电压/电流 - 输出 2:控制器 电压/电流 - 输出 3:控制器 带 LED 驱动器:无 带监控器:无 带序列发生器:是 电源电压:5.6 V ~ 24 V 工作温度:-40°C ~ 85°C 安装类型:* 封装/外壳:* 供应商设备封装:* 包装:*