UC2845 电流模式 PWM 控制器
The UC1842/3/4/5 family of control devices provides the necessary features to implement off-line or dc-to-dc fixed frequency current mode control schemes with a minimal external parts count. Internally implemented circuits include under-voltage lockout featuring start up current less than 1 mA, a precision reference trimmed for accuracy at the error amp input, logic to insure latched operation, a PWM comparator which also provides current limit control, and a totem pole output stage designed to source or sink high peak current. The output stage, suitable for driving N-Channel MOSFETs, is low in the off state.
Differences between members of this family are the under-voltage lockout thresholds and maximum duty cycle ranges
|
UC2845 |
| Topology |
Boost, Flyback, Forward |
| Control Method |
Current |
| Duty Cycle (Max) (%) |
50 |
| Frequency (Max) (kHz) |
450 |
| UVLO Thresholds On/Off (V) |
8.4/7.6 |
| Pin/Package |
14SOIC, 8PDIP, 8SOIC |
| Approx. Price (US$) |
0.65 | 1ku |
| Vin (Min) (V) |
7.6 |
| Vin (Max) (V) |
30 |
| Regulated Outputs (#) |
1 |
| Operating Temperature Range (C) |
-40 to 85 |
| Rating |
Military |
UC2845 特性
- Optimized For Off-line and DC-to-DC Converters
- Low Start-Up Current (<1 mA)
- Automatic Feed ForwardCompensation
- Pulse-by-Pulse Current Limiting
- Enhanced Load Response Characteristics
- Under-Voltage Lockout With Hysteresis
- Double Pulse Suppression
- High Current Totem Pole Output
- Internally Trimmed Bandgap Reference
- 500-kHz Operation
- Low RO Error Amp
UC2845 芯片订购指南
| 器件 |
状态 |
温度 (oC) |
价格（美元） |
封装 | 引脚 |
封装数量 | 封装载体 |
丝印标记 |
| UC2845D |
ACTIVE |
-40 to 85 |
0.75 | 1ku |
SOIC (D) | 14 |
50 | TUBE |
|
| UC2845D8 |
ACTIVE |
-40 to 85 |
0.75 | 1ku |
SOIC (D) | 8 |
75 | TUBE |
|
| UC2845D8G4 |
ACTIVE |
-40 to 85 |
0.75 | 1ku |
SOIC (D) | 8 |
75 | TUBE |
|
| UC2845D8TR |
ACTIVE |
-40 to 85 |
0.65 | 1ku |
SOIC (D) | 8 |
2500 | LARGE T&R |
|
| UC2845D8TRG4 |
ACTIVE |
-40 to 85 |
0.65 | 1ku |
SOIC (D) | 8 |
2500 | LARGE T&R |
|
| UC2845DG4 |
ACTIVE |
-40 to 85 |
0.75 | 1ku |
SOIC (D) | 14 |
50 | TUBE |
|
| UC2845DTR |
ACTIVE |
-40 to 85 |
0.65 | 1ku |
SOIC (D) | 14 |
2500 | LARGE T&R |
|
| UC2845DTRG4 |
ACTIVE |
-40 to 85 |
0.65 | 1ku |
SOIC (D) | 14 |
2500 | LARGE T&R |
|
| UC2845N |
ACTIVE |
-40 to 85 |
0.75 | 1ku |
PDIP (P) | 8 |
50 | TUBE |
|
| UC2845NG4 |
ACTIVE |
-40 to 85 |
0.75 | 1ku |
PDIP (P) | 8 |
50 | TUBE |
|
UC2845 质量与无铅数据
| 器件 |
环保计划* |
铅/焊球涂层 |
MSL 等级/回流焊峰 |
环保信息与无铅 (Pb-free) |
DPPM / MTBF / FIT 率 |
| UC2845D |
Green (RoHS & no Sb/Br) |
CU NIPDAU |
Level-1-260C-UNLIM |
UC2845D |
UC2845D |
| UC2845D8 |
Green (RoHS & no Sb/Br) |
CU NIPDAU |
Level-1-260C-UNLIM |
UC2845D8 |
UC2845D8 |
| UC2845D8G4 |
Green (RoHS & no Sb/Br) |
CU NIPDAU |
Level-1-260C-UNLIM |
UC2845D8G4 |
UC2845D8G4 |
| UC2845D8TR |
Green (RoHS & no Sb/Br) |
CU NIPDAU |
Level-1-260C-UNLIM |
UC2845D8TR |
UC2845D8TR |
| UC2845D8TRG4 |
Green (RoHS & no Sb/Br) |
CU NIPDAU |
Level-1-260C-UNLIM |
UC2845D8TRG4 |
UC2845D8TRG4 |
| UC2845DG4 |
Green (RoHS & no Sb/Br) |
CU NIPDAU |
Level-1-260C-UNLIM |
UC2845DG4 |
UC2845DG4 |
| UC2845DTR |
Green (RoHS & no Sb/Br) |
CU NIPDAU |
Level-1-260C-UNLIM |
UC2845DTR |
UC2845DTR |
| UC2845DTRG4 |
Green (RoHS & no Sb/Br) |
CU NIPDAU |
Level-1-260C-UNLIM |
UC2845DTRG4 |
UC2845DTRG4 |
| UC2845N |
Green (RoHS & no Sb/Br) |
CU NIPDAU |
N/A for Pkg Type |
UC2845N |
UC2845N |
| UC2845NG4 |
Green (RoHS & no Sb/Br) |
CU NIPDAU |
N/A for Pkg Type |
UC2845NG4 |
UC2845NG4 |
UC2845 工具与软件
UC2845 应用技术支持与电子电路设计开发资源下载
- UC2845数据资料 dataSheet 下载.PDF
- TI 德州仪器电源管理选型与价格参考 . xls
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