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MAX253
1W Primary-Side Transformer H-Bridge Driver for Isolated Supplies
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Key Features
Applications/Uses
Parametric specs for Transformer Drivers
| VIN (V) (min) | 2.5 |
| VIN (V) (max) | 6 |
| Driver Output Resistance (Ω) (max) | 4 |
| Max. IOUT (A) | 0.2 |
| Topology | Push-Pull |
| Switching Frequency (kHz) | 350 |
| IQ (mA) (max) | 0.45 |
| Package/Pins | CDIP/8 PDIP/8 SOIC (N)/8 UMAX/8 |
| Oper. Temp. (°C) | -55 to +125 -40 to +85 0 to +70 |
| Budgetary Price (See Notes) | 1.66 |
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Parameters
Parametric specs for Transformer Drivers
| VIN (V) (min) | 2.5 |
| VIN (V) (max) | 6 |
| Driver Output Resistance (Ω) (max) | 4 |
| Max. IOUT (A) | 0.2 |
| Topology | Push-Pull |
| Switching Frequency (kHz) | 350 |
| IQ (mA) (max) | 0.45 |
| Package/Pins | CDIP/8 PDIP/8 SOIC (N)/8 UMAX/8 |
| Oper. Temp. (°C) | -55 to +125 -40 to +85 0 to +70 |
| Budgetary Price (See Notes) | 1.66 |
Key Features
- Simple Power-Supply Transformer Driver Design for Isolated RS-485/RS-232 Data-Interface Applications
- Single 5V or 3.3V Supply
- Low-Current Shutdown Mode: 0.4µA
- Pin-Selectable Frequency: 350kHz or 200kHz
- 8-Pin DIP, SO, and µMAX® Packages Take Minimal Board Space
Applications/Uses
- Bridge Ground Differentials
- High Noise-Immunity Communications Interface
- Isolated and/or High-Voltage Power Supplies
- Isolated RS-485/RS-232 Power Supply
- Medical Equipment
- Process Control
- Transformer Driver
Description
The MAX253 monolithic oscillator/power-driver is specifically designed to provide isolated power for an isolated RS-485 or RS-232 data interface. The device drives a center-tapped transformer primary from a 5V or 3.3V DC power supply. The secondary can be wound to provide any isolated voltage needed at power levels up to 1W.
The MAX253 consists of a CMOS oscillator driving a pair of N-channel power switches. The oscillator runs at double the output frequency, driving a toggle flip-flop to ensure 50% duty cycle to each of the switches. Internal delays are arranged to ensure break-before-make action between the two switches.
The SD pin puts the entire device into a low-power shutdown state, disabling both the power switches and oscillator.
The MAX253 consists of a CMOS oscillator driving a pair of N-channel power switches. The oscillator runs at double the output frequency, driving a toggle flip-flop to ensure 50% duty cycle to each of the switches. Internal delays are arranged to ensure break-before-make action between the two switches.
The SD pin puts the entire device into a low-power shutdown state, disabling both the power switches and oscillator.
Technical Docs
Support & Training
Search our knowledge base for answers to your technical questions.
Filtered SearchOur dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal .
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