参数资料
| 型号： | BD9328EFJ-E2 |
| 厂商： | Rohm Semiconductor |
| 文件页数： | 9/18页 |
| 文件大小： | 0K |
| 描述： | IC REG BUCK SYNC ADJ 2A 8HTSOP |
| 标准包装： | 1 |
| 类型： | 降压（降压） |
| 输出类型： | 可调式 |
| 输出数： | 1 |
| 输出电压： | 0.9 V ~ 12.6 V |
| 输入电压： | 4.2 V ~ 18 V |
| PWM 型： | 电流模式 |
| 频率 - 开关： | 380kHz |
| 电流 - 输出： | 2A |
| 同步整流器： | 是 |
| 工作温度： | -40°C ~ 85°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 8-SOIC（0.154"，3.90mm 宽） |
| 包装： | 标准包装 |
| 供应商设备封装： | 8-HTSOP-J |
| 其它名称： | BD9328EFJ-E2DKR |
BD9328EFJ
Technical Note
(2) Loop Compensation
Choosing compensation capacitor C CMP and resistor R CMP
The current-mode buck converter has 2-poles and 1-zero system. Choosing the compensation resistor and capacitor is
important for a good load-transient response and good stability.
The example of DC/DC converter application bode plot is shown below.
The compensation resistor R CMP will decides the cross over frequency F CRS (the frequency that the total DC-DC
loop-gain falls to 0dB).
Setting the higher cross over frequency achieves good response speed, however less stability. While setting the lower
cross over frequency shows good stability but worse response speed.
The 1/10 of switching frequency for the cross over frequency shows a good performance at most applications.
( i ) Choosing phase compensation resistor R CMP
The compensation resistor R CMP can be on following formula.
R CMP =
2 π x V OUT x F CRS x C OUT
V FB x G MP x G MA
[ Ω ]
Where
V OUT ; Output voltage, F CRS ; Cross over frequency, C OUT ; Output Capacitor,
V FB ; internal feedback voltage (0.9V (TYP) ), G MP ; Current Sense Gain (7.8A/V (TYP) ) ,
G MA ; Error Amplifier Trans-conductance (300μA/V (TYP) )
Setting V OUT = 3.3V, F CRS = 38kHz, C OUT = 20μF;
R CMP =
2 π x 3.3 x 38k x 20u
0.9 x 7.8 x 300u
=
7.48k ~= 7.5k
[ Ω ]
( ii ) Choosing phase compensation capacitor CCMP
For the stability of DC/DC converter, canceling the phase delay that derives from output capacitor C OUT and
resistive load R OUT by inserting the phase advance.
The phase advance can be added by the zero on compensation resistor R CMP and capacitor C CMP .
Making Fz= F CRS / 6 gives a first-order estimate of C CMP .
Compensation Capacitor
C CMP =
1
2 π x R CMP x Fz
[F]
Setting Fz= F CRS /6 = 6.3kHz;
Compensation Capacitor
C CMP =
1
2 π x 7.5k x 6.3k
=
3.54n ~= 3.3n
[F]
( iii ) The condition of the loop compensation stability
The stability of DC/DC converter is important. To secure the operating stability, please check the loop compensation
has the enough phase-margin. For the condition of loop compensation stability, the phase-delay must be less than
150 degree where Gain is 0 dB.
Feed forward capacitor C RUP boosts phase margin over a limited frequency range and is sometimes used to
improve loop response. C RUP will be more effective if R UP >> R UP ||R DW
V OUT
Gain [dB]
A
(a)
R UP
R DW
C RUP
FB
－
＋
0.9V
COMP
R CMP
PHASE
0
0
－ 90
－ 90°
F CRS
GBW(b)
F
Fig.20
www.rohm.com
? 2011 ROHM Co., Ltd. All rights reserved.
C CMP
－ 180
9/15
PHASE MARGIN
Fig.21
－ 180°
F
2011.02 - Rev.A
相关PDF资料 |
PDF描述 |
|---|---|
| BD9329AEFJ-E2 | IC REG BUCK SYNC ADJ 3A 8HTSOP |
| BD9533EKN-E2 | IC REG SW VAR SOFT START 20-HQFN |
| BD95513MUV-E2 | IC REG BUCK ADJ 3A 32VQFN |
| BD9701T-V5 | IC REG BUCK ADJ 1.5A TO220FP |
| BD9739KN-E2 | IC REG SW BUILT IN FET 64UQFN |
相关代理商/技术参数 |
参数描述 |
|---|---|
| BD93291EFJ-E2 | 功能描述:Buck Switching Regulator IC Positive Adjustable (Fixed) 0.8V (5V) 2 Output 1.7A, 500mA 8-SOIC (0.154", 3.90mm Width) Exposed Pad 制造商:rohm semiconductor 系列:- 包装:剪切带（CT） 零件状态:有效 功能:降压 输出配置:正 拓扑:降压 输出类型:可调（固定） 输出数:2 电压 - 输入（最小值）:8V 电压 - 输入（最大值）:26V 电压 - 输出（最小值/固定）:0.8V（5V） 电压 - 输出（最大值）:4V 电流 - 输出:1.7A，500mA 频率 - 开关:300kHz ~ 600kHz，1.5MHz ~ 2.5MHz 同步整流器:是 工作温度:-40°C ~ 85°C（TA） 安装类型:表面贴装 封装/外壳:8-SOIC（0.154"，3.90mm 宽）裸焊盘 供应商器件封装:8-HTSOP-J 标准包装:1 |
| BD9329AEFJ | 制造商:ROHM 制造商全称:Rohm 功能描述:Simple Step-down Switching Regulator with Built-in Power MOSFET |
| BD9329AEFJ_EVK | 制造商:ROHM Semiconductor 功能描述:BOARD EVAL BUCK REG BD9329A |
| BD9329AEFJ-E2 | 功能描述:IC REG BUCK SYNC ADJ 3A 8HTSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:50 系列:- 类型:升压（升压） 输出类型:两者兼有 输出数:1 输出电压:5V，2 V ~ 16.5 V 输入电压:2 V ~ 16.5 V PWM 型:- 频率 - 开关:45kHz 电流 - 输出:50mA 同步整流器:无 工作温度:0°C ~ 70°C 安装类型:通孔 封装/外壳:8-DIP（0.300"，7.62mm） 包装:管件 供应商设备封装:8-PDIP |
| BD9329EFJ-E2 | 制造商:ROHM Semiconductor 功能描述:CONV DC-DC SINGLE STEP DOWN 4.2V TO 18V 8-PIN HTSOP-J T/R - Tape and Reel 制造商:ROHM Semiconductor 功能描述:IC REG BUCK SYNC ADJ 3A 8-HTSOP |
发布紧急采购，3分钟左右您将得到回复。