1. General description

The NXF6505A/B-Q100 is a specialized push-pull

transformer driver that is designed for isolated power

supplies in small form factors. This driver is capable

of driving low-profile, center-tapped transformers from

a 2.25 V to 5.5 V DC power supply, while achieving

ultra-low noise and EMI using slew rate control and

Spread Spectrum Clocking (SSC).

The NXF6505A/B-Q100 features internal protection

features such as current limiting, undervoltage lockout,

thermal shutdown, and break-before-make circuitry,

ensuring the device operates within safe limits. The

device also includes a soft-start feature that prevents

high inrush current during power-up with large load.

The NXF6505A/B-Q100 is constructed using

an oscillator and a gate drive circuit that

produces complementary output signals to drive

ground-referenced N-channel power switches.

These two complementary 1.2 A Power-MOSFET

switches can be used to provide >6 W power. The

440 kHz internal oscillator is for applications that

require higher efficiency and smaller transformers.

The NXF6505A/B-Q100 is available in a small 6 pin

SOT8061-1 package and is characterized for operation

within a temperature range of -55 °C to 125 °C.

This product has been qualified to the Automotive

Electronics Council (AEC) standard Q100 (Grade 1)

and is suitable for use in automotive applications.

2. Features and benefits

? Automotive product qualification in accordance with

AEC-Q100 (Grade 1)

? Specified from -55 °C to +125 °C

? Push-pull driver for transformers, optimized for low

EMI:

? Slew-rate control output

? Spread Spectrum Clocking (SSC)

? Wide input voltage range: 2.25 V to 5.5 V

? High output drive: 1.2 A at 5 V supply

? Low RON 0.2 Ω maximum at 5 V supply

? Internal switching frequency:

? for NXF6505A-Q100: 160 kHz

? for NXF6505B-Q100: 440 kHz

? Synchronization of multiple devices with external

clock input

? 2.2 A current limit at 5 V

? Enable pin to put device in low shutdown current:

<1 μA

? Thermal shutdown protection

? Soft-start start-up

? Small 6 pin SOT8061-1 (SC-74; TSOP-6) package

? ESD protection:

? HBM: ANSI/ESDA/JEDEC JS-001 class 3A

exceeds 6000 V

? CDM: ANSI/ESDA/JEDEC JS-002 class C3

exceeds 1500 V

3. Applications

? Isolated power supply for automotive and industrial

applications including:

? CAN, RS-485, RS-422, RS-232, SPI, I2C,

low-power LAN

? Low-noise isolated USB supplies

? Process control

? Telecom supplies

? Radio supplies

? Distributed supplies

? Medical instruments

? Precision instruments

? Low-noise filament supplies

? Motor control