HV835 SUTEX | Alldatasheet

Document overview

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Technical content

Features

Independent input control for lamp selection 160V PP output voltage Split supply capability Patented output timing One miniature inductor to power both lamps Low shutdown current Wide input voltage range 2.0V to 5.8V Output voltage regulation No SCR output Available in MLP/DFN-10 package

Applications

Dual display cellular phones Keypad and LCD backlighting Portable instrumentation Dual segment lamps Handheld wireless communication devices General Description The Supertex HV835 is a high voltage driver designed for driving two EL lamps with a combined area of 3.5 square inches. The input supply voltage range is from 2.0V to 5.8V. The device is designed to reduce the amount of audible noise emitted by the lamp. This device uses a single inductor and a minimum num- ber of passive components to drive two EL lamps. The nominal regulated output voltage of ±80V is applied to the EL lamps. The two EL lamps can be turned ON and OFF by the two logic input control pins, C 1 and C2. The device is disabled when both C1 and C2 (pins 1 and 4) are at logic low. The HV835 has an internal oscillator, a switching MOSFET, and two high voltage EL lamp drivers. Each driver has its own half bridge common output (COM1 and COM2) connected to a single pin called COM which minimizes the DC offset seen by the EL lamp. An external resistor connected between the R SW-OSC pin and the voltage supply pin, VDD, sets the frequency for the switching MOSFET. The EL lamp driver frequency is set by dividing the MOSFET switching frequency by 512. An external inductor is connected between the L X and the VDD pins. Depending on the EL lamp size, a 1.0 to 10.0nF, 100V capacitor is connected between C S and Ground. The switching MOSFET charges the external inductor and discharges it into the capacitor at C S. The voltage at CS increases. Once the voltage at CS reaches a nominal value of 80V, the switching MOSFET is turned OFF to conserve power. Typical Application Circuit HV835K7-G D 1.0µF 5 6 VDD Com GND EL2 LX CS EL1C1 RSW-OSC 1.5V 1.5V VDD VIN CIN 4.7µF CDD 0.1µF 845kΩ 3.3MΩ 3.3MΩ EL Lamp 1 EL Lamp 2 1.0µF LX 330µH CS 3.3nF, 100V

Ordering Information

MLP/DFN-10 (K7) HV835 HV835K7-G -G indicates package is RoHS compliant (‘Green’) Absolute Maximum Ratings Symbol Parameter Min Typ Max Units Conditions

Electrical Characteristics

(Over recommended operating conditions unless otherwise specifi ed: VIN = VDD = 3.3V, TA=25°C) 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. Parameter Value Supply Voltage, VDD -0.5V to 7.5V Output Voltage, VCS -0.5V to 120V Operating Temperature Range -40°C to 85°C Storage temperature -65°C to 150°C Symbol Parameter Min Typ Max Units Conditions Recommended Operating Conditions VDD Supply voltage 2.0 - 5.8 V --- TA Operating temperature -40 - +85 oC --- Pin Confi guration Thermal Resistance Package θja MLP/DFN-10 60 oC/W Note: Mounted on FR4 board, 25mm x 25mm x 1.57mm RDS(ON) On-resistance of switching transistor - - 10 Ω I = 100mA VDD Input voltage range 2.0 - 5.8 V --- VCS Output regulation voltage 72 80 88 V V DD = 2.0V to 5.8V VDIFF Differential output peak to peak voltage (EL1 to COM, EL2 to COM) 144 160 176 V V DD = 2.0V to 5.8V IDDQ Quiescent VDD supply current -- 1 5 0 n A C 1 = C2 = 0.1V - - 250 nA C 1 = C2 = 0.3V IDD Input current into the VDD pin - - 200 μA V DD = 5.8V IIN Average input current including inductor current when driving both lamps -1 6 2 5 m A V IN = 5.5V (See Figure 1) VCS Output voltage on VCS when driving both lamps -8 0- V V IN = 5.5V (See Figure 1) HV835K7-G Top View VDD RSW-OSC GND EL1 EL2 COM CS LX Pin 1 Note: Pads are on the bottom of the package. Back-side heat slug is at ground potential.

Differential output peak to peak volt- age across each lamp (EL1 to COM, EL2 to COM) - 160 - V V IN = 5.5V (See Figure 1) fEL VDIFF output drive frequency 170 200 230 Hz R SW = 845kΩ fSW Switching transistor frequency 87 102 118 kHz R SW = 845kΩ fSW temp Switching transistor frequency tempco -1 5- % T A = -40°C to +85°C D Switching transistor duty cycle - 85 - % T A = -40°C to +85°C IIL Input logic low current - - 1.0 μA V DD = 2.0V to 5.8V IIH Input logic low current - - 1.0 μA V DD = 2.0V to 5.8V VIL Logic input low voltage 0 - 0.3 V --- VIH Logic input high voltage 1.5 - V DD V --- Symbol Parameter Min Typ Max Units Conditions Electrical Characteristics (cont.) VCS Output Drivers VSENSE VREF Control logic and switch oscillator Disable Logic control and divide by 512 EL1 EL2 RSW-OSC CSLX VDD GND COM1 C COM COM2 VDD VCS VCS Function Table Logic Inputs Outputs Device C1 C2 EL1 EL2 COM 0 0 Hi Z Hi Z Hi Z OFF 0 1 H i Z O NO NO N 1 0 ON Hi Z ON ON 1 1 ON ON ON ON

  • or any (equivalent or better) > 90V, fast recovery diode Cooper LPO6610-334MLB * The bigger sized lamp should be tied to EL1 and the smaller sized lamp to EL2 (pins 10 and 9 respectively) VDD Com GND EL2 LX CS EL1C1 RSW-OSC HV835K7-G 2.1in2 EL Lamp 1* 1.8in2 EL Lamp 2* 620Ω 13nF 620Ω 11nF 1N4148* CS 3.3nF, 100V LX 330µH** 845kΩCDD 0.1µF CIN 4.7µF VIH = ON 0 = OFFVIH = ON 0 = OFF VDD VIN Lamp V DD VIN IIN VCS fEL Lamp Brightness EL1 EL2 EL1 ON 3.0V 5.2V 6.15mA 80Vpeak 200Hz 13.26 cd/m2 --- EL2 ON 5.08mA --- 13.12 cd/m 2 Both EL1 and EL2 ON 9.10mA 12.72 cd/m 2 12.23 cd/m2 EL1 ON 5.5V EL2 ON 4.76mA --- 13.24 cd/m 2 Both EL1 and EL2 ON 8.52mA 12.84 cd/m 2 12.43 cd/m2 EL1 ON 5.8V EL2 ON 4.41mA --- 13.30 cd/m 2 Both EL1 and EL2 ON 7.94mA 13.00 cd/m 2 12.55 cd/m2 Typical Performance

Pin Confi guration and Description Pin # Function Description 1C 1 Enable input signal for EL Lamp 1. Logic high will turn ON the EL lamp 1 and logic low will turn it OFF. Refer to the function table. 2V DD Input voltage supply pin. 3R SW-OSC External resistor connection to set both the switching MOSFET frequency and EL Lamp frequency. The external resistor should be connected between VDD and this pin. The EL lamp frequency is the switch- ing frequency divided by 512. The switching frequency is inversely proportional to the resistor value. A 845kΩ resistor will provide a nominal switching frequency of 102kHz and an EL lamp frequency of 200Hz. To change the frequency to f EL1, the value of the resistor RSW-OSC1 can be determined as RSW-OSC1 = (845 x 200) / fEL1 kΩ. 4C 2 Enable input signal for EL Lamp 2. Logic high will turn ON the EL lamp 2 and logic low will turn it OFF. Refer to the function table. 5 GND Device ground. 6L X Drain of internal switching MOSFET. Connection for an external inductor. When the switching MOSFET is turned ON, the inductor is being charged. When the MOSFET is turned OFF, the energy stored in the inductor is transferred to the high voltage capacitor connected at the C S pin. 7C S Connect a 100V capacitor between this pin and GND. This capacitor stores the energy transferred from the inductor. 8 COM Common lamp connection for both EL 1 and EL2. Connect one end of both the lamps to this pin. 9E L 2 EL lamp 2 connection. For optimum performance, the smaller of the two lamps should be connected to this pin.

10 EL 1

EL lamp 1 connection. For optimum performance, the larger of the two lamps should be connected to this pin. Figure 2 - Split Supply Confi guration HV835K7-G D CS LX CIN CDD 5 6 VDD Com GND EL2 LX CS EL1C1 RSW-OSC VEN = ON 0 = OFFVEN = ON 0 = OFF Regulated Voltage = VDD Battery Voltage = VIN RSW-OSC EL Lamp 1 EL Lamp 2 Split Supply Confi guration The HV835 can be used in applications operating from a battery where a regulated voltage is available. This is shown in Figure 2. The regulated voltage can be used to drive the internal logic of HV835. The amount of current used to drive the internal logic is less than 200µA. Therefore, the regu- lated voltage could easily provide the current without being loaded down.

Supertex inc.

1235 Bordeaux Drive, Sunnyvale, CA 94089

TEL: (408) 222-8888 / FAX: (408) 222-4895 www.supertex.com ©2006 Supertex inc. All rights reserved. Unauthorized use or reproduction is prohibited. Supertex inc. does not recommend the use of its products in life support applications, and will not knowingly sell its products for use in s uch applications, unless it receives an adequate "product liability indemnification insurance agreement". Supertex does not assume responsibility for use of devices described and limits its liability to the replacement of the devices determined defective due to workmanship. No responsibility is assumed for possible omissions or inaccuracies. Circuitry and spe cifications are subject to change without notice. For the latest product specifications, refer to the Supertex website: http//www.supertex.com. Doc.# DSFP - HV835 NR051806 HV835 (The package drawing(s) in this data sheet may not refl ect the most current specifi cations. For the latest package outline information go to http://www.supertex.com/packaging.html.) 10-Lead DFN/MLP (3x3) Package (K7) Top View Side View 0.30 +0.15 -0.10 1.603.00 All dimensions are in millimeters 0.50 Pin #1 Index 3.00 2.20 0.20 0.25 +0.05 -0.07 0.7 - 0.8 0.0 - 0.05