Overview
The MAX1846/MAX1847, including the MAX184BC/D variant, are high-efficiency, current-mode, inverting PWM controllers designed by Maxim Integrated, now part of Analog Devices Inc. These devices are optimized for compact, low-noise, negative-output DC-DC converters, making them suitable for various high-performance applications.
Key Specifications
| Parameter | Min | Typ | Max | Units |
|---|---|---|---|---|
| Operating Input Voltage Range | 3.0 | 16.5 | V | |
| UVLO Threshold (VIN rising) | 2.95 | V | ||
| UVLO Threshold (VIN falling) | 2.6 | V | ||
| FB Threshold | -20 | 20 | mV | |
| FB Input Current | -50 | 50 | nA | |
| Supply Current | 0.75 | 1.2 | mA | |
| Shutdown Supply Current | 10 | 25 | µA | |
| Switching Frequency | 100 | 500 | kHz | |
| Maximum Duty Cycle | 84 | 98 | % |
Key Features
- High efficiency up to 90%
- Input voltage range from +3.0V to +16.5V
- Output voltage range from -500mV to -200V
- Current-mode, constant-frequency PWM control scheme
- Internal soft-start and overcurrent protection
- Compatibility with ceramic and electrolytic output capacitors
- High-current output drivers to drive P-channel MOSFETs
- Optional clock synchronization and shutdown functions (MAX1847)
Applications
- Cellular base stations
- Networking equipment
- Optical networking equipment
- SLIC supplies
- CO DSL line driver supplies
- Industrial power supplies
- Servers
- VOIP supplies
Q & A
- What is the input voltage range of the MAX1846/MAX1847?
The input voltage range is from +3.0V to +16.5V.
- What is the output voltage range of these devices?
The output voltage range is from -500mV to -200V.
- What type of PWM control scheme do these devices use?
They use a current-mode, constant-frequency PWM control scheme.
- Can these devices operate with both ceramic and electrolytic capacitors?
- What is the maximum power output of the MAX1846/MAX1847?
The MAX1846 can deliver up to 30W, while the MAX1847 can deliver up to 70W when configured as an inverting flyback controller.
- Do these devices have internal soft-start and overcurrent protection?
- Can the MAX1847 be synchronized to an external clock?
- What are the typical applications of the MAX1846/MAX1847?
They are used in cellular base stations, networking equipment, optical networking equipment, SLIC supplies, CO DSL line driver supplies, industrial power supplies, servers, and VOIP supplies.
- What is the switching frequency range of these devices?
The switching frequency can be set from 100kHz to 500kHz.
- Do these devices have shutdown functions?
