参数资料
型号: IRDC3842W
厂商: International Rectifier
文件页数: 19/34页
文件大小: 0K
描述: BOARD EVAL FOR IR3842W 4A CONV
标准包装: 1
系列: SupIRBuck™
主要目的: DC/DC,步降
输出及类型: 1,非隔离
输出电压: 1.8V
电流 - 输出: 4A
输入电压: 12V
稳压器拓扑结构: 降压
频率 - 开关: 600kHz
板类型: 完全填充
已供物品:
已用 IC / 零件: IR3842W
PD-97659
IR3842WMPbF
the voltage Vc across C6 remains approximately
unchanged and the voltage at the Boot pin
becomes
V Boot ? V in + V cc ? V D .......... .......... .......... .......... (11)
Inductor Selection
The inductor is selected based on output power,
operating frequency and efficiency requirements.
A low inductor value causes large ripple current,
resulting in the smaller size, faster response to a
load transient but poor efficiency and high output
noise. Generally, the selection of the inductor
value can be reduced to the desired maximum
ripple current in the inductor ( Δ i ) . The optimum
point is usually found between 20% and 50%
ripple of the output current.
For the buck converter, the inductor value for the
desired operating ripple current can be
determined using the following relation:
V in ? V o = L ?
; Δ t = D ?
Fig. 12. Bootstrap circuit to generate
Vc voltage
Δ i
Δ t
L = ( V in ? V o ) ?
1
F s
V o
V in ? Δ i * F s
.......... .......... .......... . (14)
A bootstrap capacitor of value 0.1uF is suitable
for most applications.
Input Capacitor Selection
The ripple current generated during the on time of
the upper MOSFET should be provided by the
input capacitor. The RMS value of this ripple is
expressed by:
I RMS = I o ? D ? ( 1 ? D ) .......... .......... ....(12)
Where:
V in = Maximum input voltage
V o = Output Voltage
Δ i = Inductor ripple current
F s = Switching frequency
Δ t = Turn on time
D = Duty cycle
If Δ i ≈ 40%( I o ), then the output inductor is
calculated to be 1.59 μ H. Select L =1.5 μ H.
The MPO104-1R5 from Delta provides a
D =
V o
V in
.......... .......... .......... .. (13)
compact, low profile inductor suitable for this
application
Where:
D is the Duty Cycle
I RMS is the RMS value of the input capacitor
current.
Io is the output current.
For I o =4A and D = 0.15, the I RMS = 1.43 A.
Ceramic capacitors are recommended due to
their peak current capabilities. They also feature
low ESR and ESL at higher frequency which
enables better efficiency. For this application, it is
advisable to have 2x10uF 25V ceramic capacitors
C3216X5R1E106M from TDK. In addition to
these, although not mandatory, a 1X330uF, 25V
SMD capacitor EEV-FK1E331P may also be
used as a bulk capacitor and is recommended if
the input power supply is not located close to the
converter.
Rev 13.0
.
19
相关PDF资料
PDF描述
EBM10DRSI CONN EDGECARD 20POS DIP .156 SLD
A9BBG-1105F FLEX CABLE - AFF11G/AF11/AFF11G
GCA10DRSN-S288 CONN EDGECARD 20POS .125 EXTEND
A9AAT-2005E FLEX CABLE - AFH20T/AE20/AFH20T
AD588ARWZ IC VREF SERIES PREC ADJ 16-SOICW
相关代理商/技术参数
参数描述
IRDC3843 制造商:International Rectifier 功能描述:BOARD EVALUATION IR3843
IRDC3843A 功能描述:电源管理IC开发工具 IR3843 SYNC CONV 600kHz EVAL BRD RoHS:否 制造商:Maxim Integrated 产品:Evaluation Kits 类型:Battery Management 工具用于评估:MAX17710GB 输入电压: 输出电压:1.8 V
IRDC3843W 功能描述:电源管理IC开发工具 User Guide IR3843W Eval Brd RoHS:否 制造商:Maxim Integrated 产品:Evaluation Kits 类型:Battery Management 工具用于评估:MAX17710GB 输入电压: 输出电压:1.8 V
IRDC3853 功能描述:电源管理IC开发工具 User Guide IR3853 Eval Brd RoHS:否 制造商:Maxim Integrated 产品:Evaluation Kits 类型:Battery Management 工具用于评估:MAX17710GB 输入电压: 输出电压:1.8 V
IRDC3853 - SUPIRBUCK 制造商:International Rectifier 功能描述:INTERNATIONAL RECIFIER - GEN 2.1 SUPIRBUCK FAMILY - Bulk