参数资料
型号: ISL8103IRZ
厂商: Intersil
文件页数: 24/28页
文件大小: 0K
描述: IC REG CTRLR BUCK PWM VM 40-QFN
标准包装: 50
PWM 型: 电压模式
输出数: 1
频率 - 最大: 1.5MHz
占空比: 66.6%
电源电压: 4.75 V ~ 12.6 V
降压:
升压:
回扫:
反相:
倍增器:
除法器:
Cuk:
隔离:
工作温度: -40°C ~ 85°C
封装/外壳: 40-VFQFN 裸露焊盘
包装: 管件
ISL8103
(EQ. 36)
Δ V ≈ ( ESL ) ? ----- + ( ESR ) ? Δ I
L ≤ ---------------------------------- ? Δ V MAX – ( Δ I ? ESR ) ? ? V IN – V O ?
( Δ I ) 2
response, the output voltage initially deviates by an amount
as shown in Equation 36.
di
dt
( 1.25 ) ? N ? C
Switching Frequency
? ?
(EQ. 39)
[ 10.61 – 1.035 ? log ( F ) ]
R FS = 10
The filter capacitor must have sufficiently low ESL and ESR
so that Δ V < Δ V MAX .
Most capacitor solutions rely on a mixture of high frequency
capacitors with relatively low capacitance in combination
with bulk capacitors having high capacitance but limited
high-frequency performance. Minimizing the ESL of the
high-frequency capacitors allows them to support the output
voltage as the current increases. Minimizing the ESR of the
bulk capacitors allows them to supply the increased current
with less output voltage deviation.
The ESR of the bulk capacitors also creates the majority of
the output-voltage ripple. As the bulk capacitors sink and
source the inductor ac ripple current (see “Interleaving” on
page 9” and Equation 2), a voltage develops across the bulk
capacitor ESR equal to I C,P-P (ESR). Thus, once the output
capacitors are selected, the maximum allowable ripple
voltage, V PP(MAX) , determines the lower limit on the
inductance as shown in Equation 37.
There are a number of variables to consider when choosing
the switching frequency, as there are considerable effects on
the upper MOSFET loss calculation. These effects are
outlined in “MOSFETs” on page 18, and they establish the
upper limit for the switching frequency. The lower limit is
established by the requirement for fast transient response
and small output-voltage ripple as outlined in “Output Filter
Design” on page 23. Choose the lowest switching frequency
that allows the regulator to meet the transient-response
requirements.
Switching frequency is determined by the selection of the
frequency-setting resistor, R FS . Figure 23 and Equation 40
are provided to assist in selecting the correct value for R FS ..
SW (EQ. 40)
200
IN – N ? V OUT ? V OUT
? V ?
L ≥ ( ESR ) ? --------------------------------------------------------------------
? ?
F SW ? V IN ? V ( P – P ) ( MAX )
(EQ. 37)
100
Since the capacitors are supplying a decreasing portion of
the load current while the regulator recovers from the
transient, the capacitor voltage becomes slightly depleted.
The output inductors must be capable of assuming the entire
load current before the output voltage decreases more than
Δ V MAX . This places an upper limit on inductance.
50
20
Equation 38 gives the upper limit on L for the cases when
10
100k
200k
500k
1M
2M
the trailing edge of the current transient causes a greater
output-voltage deviation than the leading edge. Equation 39
addresses the leading edge. Normally, the trailing edge
dictates the selection of L because duty cycles are usually
less than 50%. Nevertheless, both inequalities should be
evaluated, and L should be selected based on the lower of
the two results. In each equation, L is the per-channel
inductance, C is the total output capacitance, and N is the
number of active channels.
SWITCHING FREQUENCY (Hz)
FIGURE 23. R FS vs SWITCHING FREQUENCY
Input Capacitor Selection
The input capacitors are responsible for sourcing the AC
component of the input current flowing into the upper
MOSFETs. Their RMS current capacity must be sufficient to
handle the AC component of the current drawn by the upper
MOSFETs which is related to duty cycle and the number of
L ≤ --------------------------------- ? Δ V MAX – ( Δ I ? ESR )
2 ? N ? C ? V O
( Δ I ) 2
24
(EQ. 38)
active phases.
FN9246.1
July 21, 2008
相关PDF资料
PDF描述
RSM08DTMT-S189 CONN EDGECARD 16POS R/A .156 SLD
ISL6845IU IC REG CTRLR BST FLYBK ISO 8MSOP
ISL6845IB-T IC REG CTRLR BST FLYBK ISO 8SOIC
RGM08DTMT-S189 CONN EDGECARD 16POS R/A .156 SLD
HMM10DRKF CONN EDGECARD 20POS DIP .156 SLD
相关代理商/技术参数
参数描述
ISL8103IRZ-T 功能描述:IC REG CTRLR BUCK PWM VM 40-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:75 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:1MHz 占空比:81% 电源电压:4.3 V ~ 13.5 V 降压:是 升压:是 回扫:是 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:0°C ~ 70°C 封装/外壳:8-SOIC(0.154",3.90mm 宽) 包装:管件 产品目录页面:1051 (CN2011-ZH PDF) 其它名称:296-2543-5
ISL8104 制造商:INTERSIL 制造商全称:Intersil Corporation 功能描述:Synchronous Buck Pulse-Width Modulator (PWM) Controller
ISL8104CBZ 功能描述:IC REG CTRLR BUCK PWM VM 14-SOIC RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:275kHz 占空比:50% 电源电压:18 V ~ 110 V 降压:无 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:是 工作温度:-40°C ~ 85°C 封装/外壳:8-SOIC(0.154",3.90mm 宽) 包装:带卷 (TR)
ISL8104CBZ-T 功能描述:IC REG CTRLR BUCK PWM VM 14-SOIC RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:275kHz 占空比:50% 电源电压:18 V ~ 110 V 降压:无 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:是 工作温度:-40°C ~ 85°C 封装/外壳:8-SOIC(0.154",3.90mm 宽) 包装:带卷 (TR)
ISL8104CRZ 功能描述:IC REG CTRLR BUCK PWM VM 16-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:275kHz 占空比:50% 电源电压:18 V ~ 110 V 降压:无 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:是 工作温度:-40°C ~ 85°C 封装/外壳:8-SOIC(0.154",3.90mm 宽) 包装:带卷 (TR)