参数资料
| 型号： | SC183CULTRT |
| 厂商： | Semtech |
| 文件页数： | 13/20页 |
| 文件大小： | 0K |
| 描述： | IC REG BUCK SYNC ADJ 2A 16MLPQ |
| 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： | 0.8 V ~ 3.3 V |
| 输入电压： | 2.9 V ~ 5.5 V |
| PWM 型： | 电压模式 |
| 频率 - 开关： | 2.5MHz |
| 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： | 16-MLPQ |
| 包装： | 标准包装 |
| 供应商设备封装： | 16-MLPQ-UT（3x3） |
| 产品目录页面： | 1357 (CN2011-ZH PDF) |
| 其它名称： | SC183CULDKR |
SC183C
Applications Information
Detailed Description
The SC183C is a synchronous step-down converter utiliz-
ing a 2.5MHz fixed frequency voltage mode architecture.
The switching frequency is chosen to minimize the size of
the external inductor and capacitors while maintaining
high efficiency.
Operation
During normal operation, the PMOS MOSFET is activated
on each rising edge of the internal oscillator. The voltage
feedback loop uses an internal feedback resistor divider.
an external resistor divider. There will be a typical 2μA
current flowing into the VOUT pin. The typical sche-
matic for an adjustable output voltage option from
the standard 1.0V with CTLx=[0010], is shown in Figure
1. RFB1 and RFB2 are used to adjust the desired out-
put voltage. If the RFB2 current is such that the 2μA
VOUT pin current can be ignored, then RFB1 can be
found by Equation 1. RFB2 needs to be low enough in
value for the current through the resistor chain to be
at least 20μA in order to ignore the VOUT pin current.
The period is set by the internal oscillator. The device has an
internal synchronous NMOS rectifier and does not require a
Schottky diode on the LX pin. The device operates as a buck
R FB 1 =
V OUT ? V OSTD
V OSTD
? R FB 2
(1)
converter in PWM mode with a fixed frequency of 2.5MHz.
Programmable Output Voltage
The SC183C has fifteen pre-determined output voltage
values which can be individually selected by program-
ming the CTL input pins (see Table 1 — Output Voltage
where V OSTD is the pre-determined output voltage via the
CTL pins.
C FF is needed to maintain good transient response perfor-
mance. The correct value of C FF can be found using
Equation 2.
Settings). Each CTL pin has an active 1 MΩ internal pull-
down resistor. The 1MΩ resistor is switched in circuit
whenever the CTL input voltage is below the input
C FF [ nF ] = 2 . 5 ×
( V OUT ? 0 . 5 ) 2
R FB 1 [ k ? ] ? ( V OUT ? V OSTD )
× (
V OSTD
V OSTD ? 0 . 5
)
(2)
threshold, or when the part is in undervoltage lockout. It
is recommended to tie all high CTL pins together and use
an external pull-up resistor to AVIN if there is no enable
signal or if the enable input is an open drain/collector
signal. The CTL pins may be driven by a microprocessor to
allow dynamic voltage adjustment for systems that reduce
the supply voltage when entering sleep states. Avoid all
zeros being present on the CTL pins when changing pro-
grammable output voltages as this would disable the
device.
To simplify the design, it is recommended to program the
desired output voltage from a standard 1.0V as shown in
Figure 1 with a proper C FF calculated from Equation 2. For
programming the output voltage from other standard
voltages, R FB1 , R FB2 and C FF need to be adjusted to meet
Equation 1and 2.
Protection Features
The SC183C provides the following protection features:
SC183C
C IN
C OUT
AVIN
SC183C is also capable of regulating a different (higher)
output voltage, which is not shown in the Table 1, via
L
V IN PVIN LX V OUT
R AVIN
10 ?
10μF
C AVIN R FB1 C FF
1μF
VOUT
?
?
?
?
Current Limit
Over-Voltage Protection
Soft-Start Operation
Thermal Shutdown
CTL0
R FB2
10k ?
R FB 1 = ( V OUT ? 1 ) × R FB 2
Enable
CTL1
CTL2
CTL3
PGND
AGND
for CTLx= 0010 (1.0V)
Current Limit
The internal PMOS power device in the switching stage is
protected by a current limit feature. If the inductor current
Figure 1 — Typical Schematic for Adjusting the
Output Voltage Up from an Output Voltage of 1.0V
(CTLx=[0010])
is above the PMOS current limit for 16 consecutive cycles,
the part enters foldback current limit mode and the
output current is limited to the current limit holding
? 2010 Semtech Corp.
13
www.semtech.com
相关PDF资料 |
PDF描述 |
|---|---|
| SC185HULTRT | IC REG BUCK SYNC 1.5V 4A 16MLPQ |
| SC186ULTRT | IC REG BUCK SYNC ADJ 4A 16MLPQ |
| SC189LULTRT | IC REG BUCK SYNC 1.8V 1.5A 6MLPD |
| SC190CIMLTRT | IC REG BUCK SYNC ADJ 0.3A 10MLP |
| SC192IMLTRT | IC REG BUCK ADJ 0.7A 10MLPD |
相关代理商/技术参数 |
参数描述 |
|---|---|
| SC18-3Q | 制造商:Thomas & Betts 功能描述:SAXXON CABLE CLIP - 8 MM |
| SC1848GH | 制造商:Rochester Electronics LLC 功能描述:- Bulk |
| SC185 | 制造商:SEMTECH 制造商全称:Semtech Corporation 功能描述:4A Synchronous Step-Down Regulator |
| SC185BEVB | 制造商:SEMTECH 功能描述:Evaluation Board For 4 A Synchronous Step-Down Regulator |
| SC185BULTRT | 功能描述:IC REG BUCK SYNC 1V 4A 16MLPQ RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:250 系列:- 类型:降压（降压） 输出类型:固定 输出数:1 输出电压:1.2V 输入电压:2.05 V ~ 6 V PWM 型:电压模式 频率 - 开关:2MHz 电流 - 输出:500mA 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:6-UFDFN 包装:带卷 (TR) 供应商设备封装:6-SON（1.45x1） 产品目录页面:1032 (CN2011-ZH PDF) 其它名称:296-25628-2 |
发布紧急采购，3分钟左右您将得到回复。