Features: · Adjustable output regulation for dimming
· 220VPP output voltage for higher brightness
· Single cell lithium ion compatible
· 150nA shutdown current
· Separately adjustable lamp and converter frequencies
· 3x3 QFN-12 package
· Split supply capabilityPinout
Specifications
| Parameter |
Value |
| VDD, Supply Voltage |
-0.5V to 6.0V |
| Operating Temperature |
-40 to +85 |
| Storage Temperature |
-65 to +150 |
| Power Dissipation QFN-12 |
1.6W |
| VCS, Output Voltage |
-0.5V to +120V |
| VREG External Input Voltage |
1.33V |
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is not implied. Continuous operation of the device at the absolute rating level may affect device reliability. All voltages are referenced to device ground. DescriptionThe Supertex HV860 is a high voltage driver designed for driving Electroluminescent, (EL), lamps of up to 5 square inches. The input supply voltage range is from 2.5V to 4.5V. The device uses a single inductor and a minimum number of passive components. Using the internal reference voltage, the regulated output voltage is at a nominal voltage of 110V. The EL lamp will therefore see ±110V. An enable pin, (EN), is available to turn the device on and off via a logic signal.
The HV860 has two internal oscillators, a switching MOSFET, and a high voltage EL lamp driver H-bridge. The frequency for the switching MOSFET is set by an external resistor connected between the RSW-OSC pin and the supply pin VDD. The EL lamp driver frequency is set by an external resistor connected between REL-OSC pin and VDD pin. An external inductor is connected between the LX and VDD pins or VIN for split supply applications. A 3.0nF capacitor is connected between CS and ground. The EL lamp is connected between VA and VB.
The HV860 switching MOSFET charges the external inductor and discharges it into the capacitor at CS. The voltage at CS will start to increase. Once the voltage at CS reaches a nominal value of 110V, the switching MOSFET is turned OFF to conserve power. The outputs VA and VB are confi gured as an H bridge and are switching in opposite states to achieve ±110V across the EL lamp.
EL lamp dimming can be accomplished by changing the HV860 input voltage to the VREG pin. The VREG pin allows an external voltage source to control the VCS amplitude. The VCS voltage is approximately 87 times the voltage seen on VREG.
HV860 Data Sheet
