Product overview
概要
The UC284xB family of control ICs 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 a trimmed oscillator for precise DUTY CYCLE CONTROL under voltage lockout featuring start-up current less than 0.5mA, 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. The UC2842B and UC2844B have UVLO thresholds of 16V (on) and 10V (off), ideally suited off-line applications The corresponding thresholds for the UC2843B and UC2845B are 8.5V and 7.9V. The UC2842B and UC2843B can operate to duty cycles approaching 100%. A range of the zero to < 50 % is obtained by the UC2844B and UC2845B by the addition of an internal toggle flip flop which blanks the output off every other clock cycle.-
All features
- LOW START-UP AND OPERATING CURRENT
- UNDERVOLTAGE LOCKOUT WITH HYSTERESIS
- INTERNALLY TRIMMED REFERENCE WITH UNDERVOLTAGE LOCKOUT
- CURRENT LIMITING
- TRIMMED OSCILLATOR FOR PRECISE FREQUENCY CONTROL
- CURRENT MODE OPERATION TO 500kHz
- OSCILLATOR FREQUENCY GUARANTEED AT 250kHz
- LATCHING PWM FOR CYCLE-BY-CYCLE
- HIGH CURRENT TOTEM POLE OUTPUT
- AUTOMATIC FEED FORWARD COMPENSATION
回路ダイアグラム
注目ビデオ
All resources
| Resource title | Latest update |
|---|
製品スペック (1)
| Resource title | Latest update | |||
|---|---|---|---|---|
| 19 Sep 2016 |
19 Sep 2016
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アプリケーションノート (1)
| Resource title | Latest update | |||
|---|---|---|---|---|
| 13 Sep 2018 |
13 Sep 2018
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Design Notes & Tips (1)
| Resource title | Latest update | |||
|---|---|---|---|---|
| 25 Jul 2018 |
25 Jul 2018
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プレゼンテーション (1)
| Resource title | Latest update | |||
|---|---|---|---|---|
| 21 Jun 2018 |
21 Jun 2018
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パンフレット (2)
| Resource title | Latest update | |||
|---|---|---|---|---|
| 23 Mar 2020 |
23 Mar 2020
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| 29 Jul 2020 |
29 Jul 2020
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EDA Symbols, Footprints and 3D Models
STMicroelectronics - UC3845B
Speed up your design by downloading all the EDA symbols, footprints and 3D models for your application. You have access to a large number of CAD formats to fit with your design toolchain.
Symbols
Footprints
3D models
品質 & 信頼性
| 製品型番 | Marketing Status | パッケージ | グレード | RoHSコンプライアンスグレード | 材料宣誓書** |
|---|---|---|---|---|---|
| UC3845BD1 |
量産中
|
SO-8 | インダストリアル | Ecopack2 | |
| UC3845BD1013TR |
量産中
|
SO-8 | インダストリアル | Ecopack2 | |
| UC3845BN |
量産中
|
DIP-8 | インダストリアル | Ecopack2 |
(**) st.comで提供している材料宣誓書は、パッケージ･ファミリ内で最も一般的に使用されているパッケージに基づく汎用ドキュメントの場合があります。そのため、特定の製品では100%正確ではない可能性があります。特定の製品情報については、セールスサポートまでお問い合わせください
サンプル & 購入
| 製品型番 | 販売代理店から購入 | STから購入 | 製品ステータス | ECCN (US) | ECCN (EU) | 梱包タイプ | パッケージ | 温度（℃） | Country of Origin | Budgetary Price (US$)*/Qty | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 最小 | 最大 | |||||||||||
| UC3845BN | 9 distributors | Buy Direct |
量産中
|
EAR99 | NEC | Tube | DIP-8 | - | - | CHINA | 0.2772 / 1k | |
| UC3845BD1 | 5 distributors | Buy Direct |
量産中
|
EAR99 | NEC | Tube | SO-8 | - | - | MOROCCO | 0.2772 / 1k | |
| UC3845BD1013TR | 4 distributors | Buy Direct |
量産中
|
EAR99 | NEC | Tape And Reel | SO-8 | - | - | MOROCCO | 0.2772 / 1k | |
（*）概算用の希望小売単価（US$）です。現地通貨でのお見積りについては、STのセールス･オフィスまたは販売代理店までお問い合わせください。
