参数资料
| 型号： | ISL6552CR-T |
| 厂商： | Intersil |
| 文件页数： | 12/18页 |
| 文件大小： | 0K |
| 描述： | IC REG CTRLR BUCK PWM 20-QFN |
| 标准包装： | 6,000 |
| PWM 型： | 控制器 |
| 输出数： | 1 |
| 频率 - 最大： | 1.5MHz |
| 电源电压： | 4.75 V ~ 5.25 V |
| 降压： | 是 |
| 升压： | 无 |
| 回扫： | 无 |
| 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： | 20-VQFN 裸露焊盘 |
| 包装： | 带卷 (TR) |
ISL6552
R FB
R IN
C c
FB
COMP
ISL6552
V IN
ERROR
AMPLIFIER
-
+
SAWTOOTH
GENERATOR
CORRECTION
+
COMPARATOR
-
+
PWM
CIRCUIT
PWM
HIP6601
Q2
Q1
L 01
I L
V CORE
-
PHASE
REFERENCE
DAC
DIFFERENCE
+
CURRENT
ISEN
R ISEN
SENSING
TO OTHER
CHANNELS
-
CURRENT
SENSING
ONLY ONE OUTPUT
STAGE SHOWN
FROM
AVERAGING
OTHER
CHANNELS
INDUCTOR
CURRENT(S)
TO OVER
CURRENT
TRIP
+
-
COMPARATOR
REFERENCE
FROM
OTHER
CHANNELS
FIGURE 7. SIMPLIFIED FUNCTIONAL BLOCK DIAGRAM SHOWING CURRENT AND VOLTAGE SAMPLING
Current Sensing and Balancing
Overview
The ISL6552 samples the on-state voltage drop across each
synchronous rectifier FET, Q2, as an indication of the
inductor current in that phase, see Figure 7. Neglecting AC
effects (to be discussed later), the voltage drop across Q2 is
simply r DS(ON) (Q2) x inductor current (I L ). Note that I L , the
inductor current, is either 1/2, 1/3, or 1/4 of the total current
(I LT ), depending on how many phases are in use.
The voltage at Q2’s drain, the PHASE node, is applied to the
R ISEN resistor to develop the I ISEN current to the ISL6552
ISEN pin. This pin is held at virtual ground, so the current
through R ISEN is I L x r DS(ON) (Q2)/R ISEN .
The I ISEN current provides information to perform the
following functions:
1. Detection of an over-current condition
2. Reduce the regulator output voltage with increasing load
current (droop)
3. Balance the I L currents in multiple channels
Over-Current, Selecting R ISEN
The current detected through the R ISEN resistor is
averaged with the current(s) detected in the other 1, 2, or 3
channels. The averaged current is compared with a
trimmed, internally generated current, and used to detect
an over-current condition.
12
The nominal current through the R ISEN resistor should be
50 μ A at full output load current, and the nominal trip point for
over-current detection is 165% of that value, or 82.5 μ A.
Therefore, R ISEN = I L x r DS(ON) (Q2)/50 μ A.
For a full load of 25A per phase, and an r DS(ON) (Q2) of
4m ? , R ISEN = 2k ? .
The over-current trip point would be 165% of 25A, or ~41A
per phase. The R ISEN value can be adjusted to change the
over-current trip point, but it is suggested to stay within ± 25%
of nominal.
Droop, Selection of R IN
The average of the currents detected through the R ISEN
resistors is also steered to the FB pin. There is no DC return
path connected to the FB pin except for R IN , so the average
current creates a voltage drop across R IN . This drop
increases the apparent V CORE voltage with increasing load
current, causing the system to decrease V CORE to maintain
balance at the FB pin. This is the desired “droop” voltage used
to maintain V CORE within limits under transient conditions.
With a high dv/dt load transient, typical of high performance
microprocessors, the largest deviations in output voltage occur
at the leading and trailing edges of the load transient. In order to
fully utilize the output-voltage tolerance range, the output
voltage is positioned in the upper half of the range when the
output is unloaded and in the lower half of the range when the
相关PDF资料 |
PDF描述 |
|---|---|
| ISL6553CB-T | IC REG CTRLR BUCK PWM 16-SOIC |
| ISL6554CB-T | IC PWM CORE VOLTAGE REG 20-SOIC |
| ISL6556ACR-T | IC CTRLR MULTIPHASE VRM10 32-QFN |
| ISL6556BCR-T | IC CTRLR MULTIPHASE VRM10 32-QFN |
| ISL6557ACB-T | IC REG CTRLR BUCK PWM VM 24-SOIC |
相关代理商/技术参数 |
参数描述 |
|---|---|
| ISL6552CRZ | 功能描述:IC REG CTRLR BUCK PWM 20-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) |
| ISL6552CRZ-T | 功能描述:IC REG CTRLR BUCK PWM 20-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) |
| ISL6553CB | 功能描述:IC REG CTRLR BUCK PWM 16-SOIC RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:4,000 系列:- PWM 型:电压模式 输出数:1 频率 - 最大:1.5MHz 占空比:66.7% 电源电压:4.75 V ~ 5.25 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 85°C 封装/外壳:40-VFQFN 裸露焊盘 包装:带卷 (TR) |
| ISL6553CB-T | 功能描述:IC REG CTRLR BUCK PWM 16-SOIC RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:4,000 系列:- PWM 型:电压模式 输出数:1 频率 - 最大:1.5MHz 占空比:66.7% 电源电压:4.75 V ~ 5.25 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 85°C 封装/外壳:40-VFQFN 裸露焊盘 包装:带卷 (TR) |
| ISL6553CBZ | 功能描述:IC REG CTRLR BUCK PWM 16-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) |
发布紧急采购，3分钟左右您将得到回复。