FM2044 FMSH 9–15V Flasher Control IC SOP14

The FMSH FM2044 is an analog ic. The integrated circuit FM2044 is used in relay-controlled automotive flashers. With two output stages, each side of the vehicle is controlled separately. A left and a right direction indicator input with only a small control current makes switch contacts for small loads possible. The separate hazard warning input simplifies the construction of the hazard switch. Lamp outage is indicated by frequency doubling during direction mode. Thanks to extreme low current consumption the FM2044 can be directly connected to the battery.

Key Specifications

Features

• Temperature and Supply Voltage
• Compensated Flashing Frequency
• Frequency Doubling Indicates Lamp Outage
• Two Relay Driver Outputs with High
• Current-carrying Capacity and Low Saturation Voltage
• Minimum Lamp Load for Flasher Operation: ≥ 1 W
• Very Low Susceptibility to EMI
• Protection According to ISO/TR7637/1 Level 4

Design Notes

• The trip threshold is specified over a tolerance band, not at a single point. Design the sense resistor against the worst-case ends of that band, or nuisance tripping will appear at temperature extremes.
• These circuits are usually supplied from a capacitive dropper or a resistive divider off the mains. Verify the supply current budget against the datasheet before adding load.
• Package choice drives creepage. For mains-referenced parts, use the widest package the layout allows and keep the specified clearance to the low-voltage side.
• Check the temperature coefficient of the threshold if the product must hold accuracy over an outdoor temperature range.

Common Questions

What is the trip threshold?

the threshold above. The threshold is specified over a tolerance band, so size the sense element against the band ends rather than the typical value.

What does this device do?

Two-relay automotive flashers controller. It integrates the control loop that would otherwise need a board of discrete parts.

Which packages are offered?

SOP14. For mains-referenced circuits choose the package that meets the creepage requirement of the layout.

How is it powered?

Typically from a capacitive dropper or resistive divider off the mains rail. Check the supply current budget in the datasheet before adding any load to that rail.