SN6505x 是一款低噪声、低 EMI 的推挽式变压器驱动器,专为小型隔离式电源而设计。该器件通过 2.25V 至 5V 的直流电源来驱动薄型、
中间抽头的变压器。通过输出开关电压的转换速率控制和扩频时钟 (SSC) 可实现超低噪声和 EMI。SN6505x 包含一个振荡器,然后是一个栅极驱动器电路,此电路提供补偿输出信号以驱动接地参考 N 通道电源开关。该器件包含两个 1A 电源 MOSFET 开关,以确保在重负载条件下正常启动。开关时钟也可由外部提供,以准确放置开关谐波或者在与多个变压器驱动器搭配工作时。内部保护特性包括 1.7A 限流、欠压锁定、热关断和先断后合电路。SN6505x 具有软启动功能,可防止大负载电容器在上电过程中出现高浪涌电流。SN6505A 有 160kHz 内部振荡器,适用于需要大幅降低辐射的应用;而 SN6505B 有 420kHz 内部振荡,适用于需要更高效率和更小变压器尺寸的应用。SN6505x 采用小型 6 引脚 SOT23/DBV 封装。该器件的运行温度范围为 –55°C 至 125°C。
器件型号 | 封装 | 封装尺寸(标称值) |
---|---|---|
SN6505A | SOT23(6 引脚) | 2.90mm × 1.60mm |
SN6505B |
Changes from Revision H (July 2019) to Revision I (August 2023)
Changes from Revision G (November 2018) to Revision H (July 2019)
Changes from Revision F (September 2016) to Revision G (November 2018)
Changes from Revision E (August 2016) to Revision F (September 2016)
Changes from Revision D (August 2016) to Revision E (August 2016)
Changes from Revision C (August 2016) to Revision D (August 2016)
Changes from Revision B (February 2016) to Revision C (August 2016)
Changes from Revision A (October 2015) to Revision B (February 2016)
Changes from Revision * (September 2015) to Revision A (October 2015)
PIN | DESCRIPTION | ||
---|---|---|---|
NAME | NO. | TYPE | |
D1 | 1 | O | Open drain output of the first power MOSFETs. Typically connected to the outer terminals of the center tap transformer. Because large currents flow through these pins, their external traces should be kept short. |
VCC | 2 | P | This is the device supply pin. It should be bypassed with a 4.7 μF or greater, low ESR capacitor. When VCC ≤ 2.25 V, an internal undervoltage lockout circuit trips and turns both outputs off. |
D2 | 3 | O | Open drain output of the second power MOSFETs. Typically connected to the outer terminals of the center tap transformer. Because large currents flow through these pins, their external traces should be kept short. |
GND | 4 | P | GND is connected to the source of the power MOSFET switches via an internal sense circuit. Because large currents flow through it, the GND terminals must be connected to a low-inductance quality ground plane. |
EN | 5 | I | The EN pin turns the device on or off. Grounding or leaving this pin floating disables all internal circuitry. If unused this pin should be tied directly to VCC. |
CLK | 6 | I | This pin is used to run the device with external clock. Internally it is pulled down to GND. If valid clock is not detected on this pin, the device shifts automatically to internal clock. |