ADM8845: Charge Pump Driver for 6 White LED LCD Backlights |
The ADM8845 provides the power required to drive up to 6 white LEDs from a 2.6 V to 5.5 V (li-ion) input supply, using charge pump technology. The white LEDs are used for backlighting a color LCD display. To maximize power efficiency, a charge pump that can operate in either of a 1x, 1.5x or 2x mode is used. The Charge Pump automatically switches between 1x/1.5x/2x modes based on the input ...続きを見る
The ADM8845 provides the power required to drive up to 6 white LEDs from a 2.6 V to 5.5 V (li-ion) input supply, using charge pump technology. The white LEDs are used for backlighting a color LCD display. To maximize power efficiency, a charge pump that can operate in either of a 1x, 1.5x or 2x mode is used. The Charge Pump automatically switches between 1x/1.5x/2x modes based on the input voltage, to maintain correct output levels at a high power efficiency.
Improved brightness matching of the white LEDs is achieved by the use of a feedback pin to sense each individual LED current with a maximum matching accuracy of 1% and ISET to ILED maximum matching of 1%.
The ADM8845 provides two digital input control pins, CTRL1 and CTRL2, which control the shutdown operation and the brightness of the LEDs. The LEDs are arranged into two groups, main and sub display options, the main display refers to 4 of the 6 LEDs (FB1 -FB4) and the sub display refers to the remaining 2 LEDs (FB5 - FB6). Brightness control of the white LEDs can be achieved with a digital PWM signal applied to CTRL1 and/or CTRL2 to provide brightness control on the main and/or sub displays. The duty cycle of the applied digital PWM signal determines the brightness of the backlight white LEDs. Also brightness control of the white LEDs can be controlled using a DC voltage or a PWM signal applied to the ISET pin with a few external components added.
The ADM8845 also has soft-start circuitry to limit inrush current flow at power up.
The ADM8845 is fabricated using CMOS technology for minimal power consumption. The part is packaged in a 16-pin LFCSP package.
For more information on the ADM8845, contact the Supervisory-Interface Product Group and supply your name, company, mailing address, telephone/fax numbers, email address, and a brief description of your application.
| Part# | Input Voltage Range (Vcc) | Vout Adjust Options | Iout (max) (mA) | Switching Frequency (MHz) | Package | Price* (1000-4999) |
|---|---|---|---|---|---|---|
| ADM8843 | 2.6 to 5.5V | - | 20 | 1.5 | 16-LFCSP | $0.50 |
| ADM8845 | 2.6 to 5.5V | - | 30 | - | 16-LFCSP | $0.71 |
| ADP1610 | 2.5 to 5.5 V | Vin to 12 V | 1.2 | 1.2 | 8-MSOP | $1.12 |
| ADP1611 | 2.5 to 5.5 V | Vin to 20 V | 1.2 | 1.2 | 8-MSOP | - |
| ADP1653 | 2.75 to 5.5 V | - | 500 | 1.2 | 16-LFCSP | $1.45 |
| ADP1655 | 2.75 to 5.5 V | - | 500 | 2 | 12-WLCSP | $0.95 |
| ADP5520 | 2.27 to 5.5 V | - | 30 | 1 | - | $1.66 |
* The pricing listed here is provided only for budgetary purposes as recommended list price in U.S.
Dollars in the United States ex factor per unit for the stated volume. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.
** Pricing is currently unavailable. Click on the product number to see the Product Page for additional information.
| モデル | 製品状況 | パッケージ | ピン数 | 動作 温度範囲 |
価格* (1000 pcs.) |
Production** Availability |
RoHS互換 | PCN | サンプル・カート | 購入カート |
|---|---|---|---|---|---|---|---|---|---|---|
| ADM8845ACP-REEL | 製造中 | 16 ld LFCSP (3x3mm, 1.3mm exposed pad) | 16 | 工業用 | $0.71 | - | N 成分表 | - | お問い合わせ | お問い合わせ |
| ADM8845ACP-REEL7 | 最終購入可能日 | 16 ld LFCSP (3x3mm, 1.3mm exposed pad) | 16 | 工業用 | $0.71 | - | N 成分表 | - | カートに入れる | カートに入れる |
| ADM8845ACPZ-REEL | 製造中 | 16 ld LFCSP (3x3mm, 1.3mm exposed pad) | 16 | 工業用 | $0.71 | - | Y 成分表 | - | お問い合わせ | お問い合わせ |
| ADM8845ACPZ-REEL7 | 製造中 | 16 ld LFCSP (3x3mm, 1.3mm exposed pad) | 16 | 工業用 | $0.71 | - | Y 成分表 | - | カートに入れる | カートに入れる |
| ADM8845EB-EVALZ | 製造中 | EVALUATION BOARDS | - | TBD | $151.80 | 11/27/2009 | Y | - | お問い合わせ | カートに入れる |
*価格は1個当たりの米ドルで、米国内における販売価格(FOB)で表示されておりますので、予算のためにのみご使用いただけます。 また、その価格は変更されることがあります。米国以外のお客様への価格は、輸送費、各国の税金、手数料、為替レートにより決定されます。価格・納期等の詳細情報については、弊社正規販売代理店または担当営業にお問い合わせください。なお、 評価用ボードおよび評価用キットの表示価格は1個構成としての価格です。
**製品購入よりもサンプル注文の方が早く届く場合があります。入手性については、カートの中の「Availability」の欄をご覧ください。