參數(shù)資料
型號: ISL97644
廠商: Intersil Corporation
英文描述: Boost + LDO + VON Slice + VCOM
中文描述: 升壓穩(wěn)壓器馮片威科姆
文件頁數(shù): 11/15頁
文件大小: 544K
代理商: ISL97644
11
FN9228.0
April 11, 2006
Inductor
The boost inductor is a critical part which influences the
output voltage ripple, transient response, and efficiency.
Values of 3.3μH to 10μH are used to match the internal
slope compensation. The inductor must be able to handle
the following average and peak current:
I
1
D
I
L
2
Some inductors are recommended in Table 3.
Rectifier Diode
A high-speed diode is necessary due to the high switching
frequency. Schottky diodes are recommended because of
their fast recovery time and low forward voltage. The reverse
voltage rating of this diode should be higher than the
maximum output voltage. The rectifier diode must meet the
output current and peak inductor current requirements. The
following table is some recommendations for boost converter
diode.
Output Capacitor
The output capacitor supplies the load directly and reduces
the ripple voltage at the output. Output ripple voltage
consists of two components: the voltage drop due to the
inductor ripple current flowing through the ESR of output
capacitor, and the charging and discharging of the output
capacitor.
For low ESR ceramic capacitors, the output ripple is
dominated by the charging and discharging of the output
capacitor. The voltage rating of the output capacitor should
be greater than the maximum output voltage.
Note: Capacitors have a voltage coefficient that makes their
effective capacitance drop as the voltage across then
increases. C
OUT
in the equation above assumes the
effective value of the capacitor at a particular voltage and not
the manufacturer’s stated value, measured at zero volts.
The following table shows some selections of output
capacitors.
Compensation
The boost converter of ISL97644 can be compensated by a
RC network connected from CM1 pin to ground. 4.7nF and
10k RC network is used in the demo board. The larger value
resistor and lower value capacitor can lower the transient
overshoot, however, at the expense of stability of the loop.
Cascaded MOSFET Application
An 20V N-channel MOSFET is integrated in the boost
regulator. For the applications where the output voltage is
greater than 20V, an external cascaded MOSFET is needed
as shown in Figure 15. The voltage rating of the external
MOSFET should be greater than A
VDD
.
Linear-Regulator (LDO)
The ISL97644 includes a LDO with adjustable output, and it
can supply current up to 350mA. The output voltage is
adjusted by connection of ADJ pin. When ADJ pin is
connected to ground, the output voltage is set to 3.3V; when
ADJ pin is floating, the output voltage is set to 2.85V, and
when ADJ pin is connected to LDO_OUT pin, the output
voltage is set to 2.5V.
TABLE 3. BOOST INDUCTOR RECOMMENDATION
INDUCTOR
DIMENSIONS
(mm)
MFG
PART NUMBER
6.8μH/3A
PEAK
7.3x6.8x3.2
TDK
RLF7030T-6R8N3R0
10μH/4A
PEAK
8.3X8.3X4.5
Sumida
CDR8D43-100NC
5.2μH/4.55A
PEAK
10x10.1x3.8
Cooper
Bussmann
CD1-5R2
TABLE 4. BOOST CONVERTER RECTIFIER DIODE
RECOMMENDATION
DIODE
V
R
/I
AVG
RATING
PACKAGE
MFG
SS23
30V/2A
SMB
Fairchild
Semiconductor
MBRS340
40V/3A
SMC
International
Rectifier
SL23
30V/2A
SMB
Vishay
Semiconductor
I
LAVG
-------------
=
I
LPK
I
LAVG
--------
+
=
V
RIPPLE
I
LPK
ESR
V
-----------------------
V
O
I
OUT
---------------
1
f
s
---
×
×
+
×
=
TABLE 5. BOOST OUTPUT CAPACITOR RECOMMENDATION
CAPACITOR
SIZE
MFG
PART NUMBER
10μF/25V
1210
TDK
C3225X7R1E106M
10μF/25V
1210
Murata
GRM32DR61E106K
FIGURE 15. CASCADED MOSFET TOPOLOGY FOR HIGH
OUTPUT VOLTAGE APPLICATIONS
Intersil
ISL97644
LX
FB
A
VDD
V
IN
ISL97644
相關(guān)PDF資料
PDF描述
ISL97644IRZ Boost + LDO + VON Slice + VCOM
ISL97644IRZ-T Boost + LDO + VON Slice + VCOM
ISL97644IRZ-TK Boost + LDO + VON Slice + VCOM
ISL97645 Boost + VON Slice + VCOM
ISL97645IRZ Boost + VON Slice + VCOM
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
ISL97644IRZ 制造商:Rochester Electronics LLC 功能描述: 制造商:Intersil Corporation 功能描述:
ISL97644IRZ-T 功能描述:IC REG BOOST LDO VON VCOM 24-QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 電源管理 - 專用 系列:- 應(yīng)用說明:Ultrasound Imaging Systems Application Note 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:37 系列:- 應(yīng)用:醫(yī)療用超聲波成像,聲納 電流 - 電源:- 電源電壓:2.37 V ~ 6 V 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:56-WFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:56-TQFN-EP(8x8) 包裝:管件
ISL97644IRZ-TK 功能描述:IC REG BOOST LDO VON VCOM 24-QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 電源管理 - 專用 系列:- 應(yīng)用說明:Ultrasound Imaging Systems Application Note 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:37 系列:- 應(yīng)用:醫(yī)療用超聲波成像,聲納 電流 - 電源:- 電源電壓:2.37 V ~ 6 V 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:56-WFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:56-TQFN-EP(8x8) 包裝:管件
ISL97645AIRZ 功能描述:IC REG BOOST VON VCOM 24-QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 電源管理 - 專用 系列:- 應(yīng)用說明:Ultrasound Imaging Systems Application Note 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:37 系列:- 應(yīng)用:醫(yī)療用超聲波成像,聲納 電流 - 電源:- 電源電壓:2.37 V ~ 6 V 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:56-WFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:56-TQFN-EP(8x8) 包裝:管件
ISL97645AIRZ-T 功能描述:IC REG BOOST VON VCOM 24-QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 電源管理 - 專用 系列:- 應(yīng)用說明:Ultrasound Imaging Systems Application Note 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:37 系列:- 應(yīng)用:醫(yī)療用超聲波成像,聲納 電流 - 電源:- 電源電壓:2.37 V ~ 6 V 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:56-WFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:56-TQFN-EP(8x8) 包裝:管件