LMG2610 は、スイッチ・モード電源アプリケーションの 75W 未満のアクティブ・クランプ・フライバック (ACF) コンバータに適した 650V GaN パワー FET ハーフブリッジです。LMG2610 は、ハーフブリッジ・パワー FET、ゲート・ドライバ、ブートストラップ・ダイオード、ハイサイド・ゲート・ドライブ・レベル・シフタを 9mm x 7mm の QFN パッケージに統合することで、設計の簡素化、部品点数の低減、基板面積の低減を実現しています。
GaN FET の非対称の抵抗値は、ACF の動作条件に合わせて最適化されています。プログラマブルなターンオン・スルーレートにより、EMI とリンギングを制御できます。ローサイド電流検出エミュレーションにより、従来の電流検出抵抗方式よりも消費電力を低減でき、またローサイドのサーマル・パッドを冷却用 PCB 電源グランドに接続できます。
ハイサイド・ゲート・ドライブ信号レベル・シフタにより、外付けソリューションに見られるノイズとバースト・モード電力消費の問題を解消できます。スマート・スイッチ付き GaN ブートストラップ FET を使うと、ダイオードの順方向電圧降下がなく、ハイサイド電源を過充電せず、逆方向回復電荷がありません。
LMG2610 は、小さい静止電流と高速な起動時間によって、コンバータの軽負荷効率要件とバースト・モード動作に対応しています。保護機能には、FET ターンオン・インターロック、低電圧誤動作防止 (UVLO)、サイクル単位の電流制限、過熱シャットダウンが含まれます。
部品番号 | パッケージ (1) | 本体サイズ (公称) |
---|---|---|
LMG2610 | QFN | 9.00mm × 7.00mm |
Changes from Revision * (October 2022) to Revision A (December 2022)
PIN | TYPE(1) | DESCRIPTION | |
---|---|---|---|
NAME | NO. | ||
NC1 | 1, 13 | NC | Used to anchor QFN package to PCB. Pins must be soldered to PCB landing pads. The PCB landing pads are non-solder mask defined pads and must not be physically connected to any other metal on the PCB. Internally connected to DH. |
DH | 2-12 | P | High-side GaN FET drain. Internally connected to NC1. |
SW | 14-16 | P | GaN FET half-bridge switch node between the high-side GaN FET source and low-side GaN FET drain. Internally connected to PADH. |
NC2 | 17, 21, 37 | NC | Used to anchor QFN package to PCB. Pins must be soldered to PCB landing pads. The PCB landing pads are non-solder mask defined pads and must not be physically connected to any other metal on the PCB. Internally connected to AGND, SL, and PADL. |
SL | 18-20, 22-27 | P | Low-side GaN FET source. Internally connected to AGND, PADL, and NC2. |
EN | 28 | I | Enable. Used to toggle between active and standby modes. The standby mode has reduced quiescent current to support converter light load efficiency targets. There is a forward biased ESD diode from EN to AUX so avoid driving EN higher than AUX. |
INH | 29 | I | High-side gate-drive control input. Referenced to AGND. Signal is level shifted internally to the high-side GaN FET driver. There is a forward biased ESD diode from INH to AUX so avoid driving INH higher than AUX. |
INL | 30 | I | Low-side gate-drive control input. Referenced to AGND. There is a forward biased ESD diode from INL to AUX so avoid driving INL higher than AUX. |
AGND | 31 | GND | Low-side analog ground. Internally connected to SL, PADL, and NC2. |
CS | 32 | O | Current-sense emulation output. Outputs 1 ma/A scaled replica of the low-side GaN FET current. Feed output current into a resistor to create a current sense voltage signal. Reference the resistor to the power supply controller IC local ground. This function replaces the external current-sense resistor that is used in series with the low-side FET. |
NC3 | 33 | NC | Used to anchor QFN package to PCB. Pin must be soldered to a PCB landing pad. The PCB landing pad is non-solder mask defined pad and must not be physically connected to any other metal on the PCB. Pin not connected internally. |
FLT | 34 | O | Active-low fault output. Open-drain output that asserts during an over-temperature shut down. |
AUX | 35 | P | Auxiliary voltage rail. Low-side supply voltage. Connect a local bypass capacitor between AUX and AGND. |
RDRVL | 36 | I | Low-side drive strength control resistor. Set a resistance between RDRVL and AGND to program the low-side GaN FET turn-on slew rate. |
BST | 38 | P | Bootstrap voltage rail. High-side supply voltage. The bootstrap diode function between AUX and BST is internally provided. Connect an appropriately sized bootstrap capacitor between BST and SW. Recommend to make the SW connection using NC4 as a pass through connection to PADH (PADH = SW) as explained in the NC4 description. |
RDRVH | 39 | I | High-side drive strength control resistor. Set a resistance between RDRVH and SW to program the high-side GaN FET turn-on slew rate. Recommend to make the SW connection using NC4 as a pass through connection to PADH (PADH = SW) as explained in the NC4 description. |
NC4 | 40 | NC | Pin is not functional. Pin is high impedance and referenced to SW. Recommend to connect pin to PADH (PADH = SW) to use as convenient connection for the BST bypass capacitor and the RDRVH resistor. See the example board layout in the Layout Example section. |
PADH | 41 | TP | High-side thermal pad. Internally connected to SW. All the SW current can be conducted with PADH (PADH = SW). |
PADL | 42 | TP | Low-side thermal pad. Internally connected to SL, AGND, and NC2. All the SL current can be conducted with PADL (PADL = SL). |