Press Release Summary:
MIC4826 and MIC4827 electroluminescent lamp driver ICs independently set boost converter frequency and EL lamp frequency. Lamps accept 1.8 to 5.5 V input range, allowing direct operation from two-cell Alkaline/NiCad/NiMH or one-cell Li Ion batteries. MIC4826/7 are housed in MSOP-8 packages, require 6 external passive components, and have peak-to-peak regulated AC outputs voltages of 160V and 180V respectively.
Original Press Release:
Micrel Releases Electroluminescent Lamp Driver IC's
Micrel Releases Electroluminescent Lamp Driver ICs
...flexible architecture allows designers to maximize lamp brightness and efficiency by independently setting the boost converter frequency and EL lamp frequency.
...wide 1.8V to 5.5V input voltage range allows direct operation from many battery types
SAN JOSE, Calif - (November 12, 2001) - Micrel has released its first electroluminescent (EL) lamp driver ICs. The MIC4826 and MIC4827, were designed and developed by Micrel Semiconductor (NASDAO: MCRL), an industry leader in analog, power management and high-speed communications integrated circuits.
EL lamps are becoming the solution of choice for providing backlight to LCD panels and keypads used in cellular phones, PDAs, pagers, and remote controls. LEDs have traditionally been used to provide the backlight in these portable applications.
However, EL panels provide a much more uniform brightness in a flatter area while consuming less power, thereby saving battery life. A high-voltage AC waveform is needed to light-up EL panels, but typically only a low voltage battery is available as the power source. The MIC4826/7 solve this design challenge. The ICs converts a 1.8V to 5.5V DC input voltage to a high voltage AC signal that drives the EL lamp. The MIC4826 generates a 160V and the MIC4827 generates a 180V peak-to-peak AC output voltage. The MIC4827 is intended for applications which require the maximum EL brightness.
Their 1.8V to 5.5V input voltage ranges make the MIC4826/7 capable of operating directly from 2-cell Alkaline/NiCad/NiMH or 1-cell Li Ion batteries. Competing solutions have a narrower input voltage range, requiring more complex split-supply approaches to be taken.
The MIC4826/7 give designers a lot of flexibility without sacrificing board space. Both the boost converter oscillator frequency and the EL lamp frequency are independently adjustable via external resistors. This feature lets designers tune efficiency versus brightness for a given EL lamp size. Many competing solutions offer only a fixed ratio of boost frequency versus EL lamp frequency. Board space is kept to a minimum as the MIC4826/7 are housed in a small MSOP-8 package, and require only 6 external passive components.
"The MIC4826 and MIC4827 family offers a small, simple, and efficient solution for driving EL lamps. Their flexible architecture allows designers to maximize lamp brightness and efficiency by independently setting the boost converter frequency and EL lamp frequency" says Tony Grizelj, Micrel's marketing manager for power products.
The MIC4826BMM and MIC4827BMM are available in the MSOP-8 package. The MIC4826 is priced at $1.18, and the MIC4827 is priced at $1.28 when purchased in 1,000-piece quantities. Samples are available from stock, and production quantities are stock to 12 weeks ARO.
Summary of Features & Applications:
* MIC4826 and MIC4827 EL Drivers
* 1.8V to 5.5V DC input voltage range
* 160V peak-to-peak regulated AC output voltage (MIC4826)
* 180V peak-to-peak regulated AC output voltage (MIC4827)
* Adjustable EL lamp frequency
* Adjustable boost converter frequency
* 0.1 µA max shutdown current Applications
* Cellular phones
* Portable phones