Overview
The SN6505BDBVT from Texas Instruments is a low-noise, 1-A, 420-kHz transformer driver designed for isolated power supplies in small form factors. This device is part of the SN6505x series and is specifically tailored to drive low-profile, center-tapped transformers from a 2.25 V to 5.5 V DC power supply. It features ultra-low noise and EMI, achieved through slew rate control of the output switch voltage and Spread Spectrum Clocking (SSC). The SN6505BDBVT includes internal protection features such as current limiting, under-voltage lockout, thermal shutdown, and break-before-make circuitry, ensuring reliable operation across a wide temperature range of –55°C to 125°C.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Package | SOT-23 (DBV) | |
| Pins | 6 | |
| Operating Temperature Range | –55 to 125 | °C |
| Input Voltage Range | 2.25 to 5.5 | V |
| Output Drive Current | 1 A at 5 V supply | |
| RON (Maximum) | 0.25 Ω at 4.5 V supply | |
| Internal Oscillator Frequency | 420 kHz | |
| Current Limit | 1.7 A | |
| Shutdown Current | <1 µA | |
| Thermal Shutdown | Yes |
Key Features
- Push-pull driver for transformers
- Wide input voltage range: 2.25 V to 5.5 V
- High output drive: 1 A at 5 V supply
- Low RON: 0.25 Ω max at 4.5 V supply
- Ultra-low EMI and Spread Spectrum Clocking (SSC)
- Precision internal oscillator options: 420 kHz for SN6505B
- Synchronization of multiple devices with external clock input
- Slew-rate control
- 1.7 A Current-limit
- Low shutdown current: <1 µA
- Thermal shutdown
- Wide temperature range: –55°C to 125°C
- Small 6-Pin SOT23 (DBV) package
- Soft-start to reduce In-rush current
Applications
- Isolated power supply for 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
Q & A
- What is the primary function of the SN6505BDBVT?
The SN6505BDBVT is a low-noise, 1-A, 420-kHz transformer driver designed for isolated power supplies. - What is the input voltage range of the SN6505BDBVT?
The input voltage range is 2.25 V to 5.5 V. - What is the maximum output drive current of the SN6505BDBVT?
The maximum output drive current is 1 A at a 5 V supply. - What is the RON (on-resistance) of the SN6505BDBVT?
The RON is 0.25 Ω maximum at a 4.5 V supply. - Does the SN6505BDBVT have internal protection features?
Yes, it includes current limiting, under-voltage lockout, thermal shutdown, and break-before-make circuitry. - What is the operating temperature range of the SN6505BDBVT?
The operating temperature range is –55°C to 125°C. - Can the SN6505BDBVT be synchronized with external clock inputs?
Yes, it supports synchronization of multiple devices with an external clock input. - What is the purpose of the soft-start feature in the SN6505BDBVT?
The soft-start feature reduces inrush current during power-up with large load capacitors. - In what package is the SN6505BDBVT available?
The SN6505BDBVT is available in a small 6-pin SOT23 (DBV) package. - What are some common applications of the SN6505BDBVT?
Common applications include isolated power supplies for various communication protocols, low-noise isolated USB supplies, process control, telecom supplies, and medical instruments.
