LM2422TE NSC | Alldatasheet

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Absolute Maximum Ratings(Notes 1, If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage (V CC) +250V Bias Voltage (VBB) +16V Input Voltage (VIN) −0.5V to V BB +0.5V Storage Temperature Range (TSTG) −65˚C to +150˚C Lead Temperature (Soldering, <10 sec.) 300˚C ESD Tolerance, Human Body Model 2 kV Machine Model 200V Junction Temperature 150˚C θ JC (typ) 1.8˚C/W Operating Ratings(Note 2) VCC +100V to +230V VBB +7V to +13V VIN +0V to +5V VOUT +40V to +215V Case Temperature (22W max power) 110˚C Do not operate the part without a heat sink. Heat sink must have a thermal resistance under 2.3˚C/W. (Note 7)

Electrical Characteristics

(See Figure 3for Test Circuit). Unless otherwise noted: V CC = +220V, VBB = +12V, CL = 10 pF, T C = 60˚C. DC Tests: VIN = +2.7VDC. AC Tests: Output = 110V PP (80V – 190V) at 1 MHz. Symbol Parameter Conditions LM2422 UnitsMin Typ Max ICC Supply Current No Input Signal, No Video Input, No Output Load 36 45 54 mA IBB Bias Current 18 27 36 mA VOUT, 1 DC Output Voltage No AC Input Signal, V IN = 2.7VDC 124 129 134 V DC VOUT, 2 DC Output Voltage No AC Input Signal, V IN = 1.2VDC 200 205 210 V DC AV DC Voltage Gain No AC Input Signal −49 −52 −55 V/V ∆AV Gain Matching (Note 4), No AC Input Signal 1.0 dB LE Linearity Error (Notes 4, 5), No AC Input Signal 8 % t r Rise Time, 80V to 190V (Note 6), 10% to 90% 12 ns +OS Overshoot 12 % tf Fall Time, 80V to 190V (Note 6), 90% to 10% 12 ns −OS Overshoot (Note 6) 4 % Ik ERROR Current Output Error Output Curren t=0µ At o2 0 0µ A − 5 2 0 5 2 µ A ∆IkERROR Current Output Difference Between Channels Output Current=0µ At o2 0 0µ A 0N A 3 2 µ A Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Note 2: Operating ratings indicate conditions for which the device is functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. Datasheet min/max specification limits are guaranteed by design, test, or statistical analy sis. The guaranteed specifications apply only for the test conditions listed. Some performance characteristics may change when the device is not operated under the list ed test conditions. Note 3: All voltages are measured with respect to GND, unless otherwise specified. Note 4: Calculated value from Voltage Gain test on each channel. Note 5: Linearity Error is the variation in DC gain from V IN = 1.15V to V IN = 4.35V. Note 6: Input from signal generator: t r,t f < 1 ns. Note 7: Running the 1 MHz to 30 MHz test pattern at 1080i this part will dissipate approximately 22 W. This is the commonly accepted test pattern that is representative of the worst case high frequency content for normal television viewing. This is the pattern used to estimate the worst case power dissi pation of the LM2422 in its normal application. It is recommended to use a heat sink with a thermal resistance of 2.3˚C/W or better. LM2422TE www.national.com 2

Application Hints (Continued) same area of the ground trace as D2. The diode placement and routing is very important for minimizing the voltage stress on the LM2422 during an arc over event. This demonstration board uses large PCB holes to accom- modate socket pins, which function to allow for multiple insertions of the LM2422 in a convenient manner. To benefit from the enhanced LM2422 package with thin leads, the device should be secured in small PCB holes to optimize the metal-to-metal spacing between the leads. CURRENT OUTPUT FOR IK FEEDBACK SYSTEMS The LM2422 can be used in DTV applications that use an IK feedback system. Figure 14 shows an example of an inter- face circuit used to feed back the IK output of LM2422 to a preamplifier with an ac coupled IK input. This feedback system consists of the preamp, LM2422, and interface circuit, forming a closed loop to automatically ad- just the black level of the drive signals to the cutoff point of the RGB cathodes. Following is a description of the interface circuit operation. The output at pin 9 of the LM2422 is filtered of high fre- quency noise by C14. D7 is used to limit the peak voltage at pin 9. Without this clamp diode the voltage would easily exceed 12V during active video, in which the cathode cur- rents are much greater than the small currents being de- tected during vertical blanking. Exceeding 12V could dam- age Q1 and result in improper operation of the driver. R35 is essential to convert the IK current to voltage. Choos- ing the value of R35 sets the gain of the feedback voltage, and consequently, the operating point of the tube. Once a stable operating point is established, this point can be fine- tuned using the adjustment range of the feedback system or standard preamp controls. Changing the value of R35 will change the cutoff voltage at the cathode. A smaller value of R35 requires more IK current to maintain the feedback loop. The cutoff voltage set at the cathode will be lower to adjust to the higher IK current. This additional current must come from the cathode; therefore, the cathode voltage is lower to meet higher current requirement. A higher value of R35 will do the opposite, raising the cathode voltage because less IK cur- rent is needed to maintain the same voltage at R35. The emitter follower, Q1, isolates R35 from the input imped- ance of the preamp. R20 and R21 bias the emitter of Q1 to limit the maximum voltage to the preamp. These resistor values should be chosen to limit the maximum voltage at the emitter and protect the preamp from any large voltages that would otherwise occur during active video. C12 is used for further filtering of the IK signal. C9 is used to AC couple the IK signal to the preamp. The advantage of AC coupling is that any DC component (leakage current from the driver) of the IK signal is not detected by the IK sense input of the preamp. LM2422TE www.national.com9

FIGURE 14. LM2422 DTV Applications Circuit

FIGURE 15. LM2422 DTV Demonstration Board Layout

FIGURE 16. Trace Routing and Component Placement for Blue Channel Output

Physical Dimensions inches (millimeters) unless otherwise noted NOTE: Available only with lead free plating Order Number LM2422TE THE CONTENTS OF THIS DOCUMENT ARE PROVIDED IN CONNECTION WITH NATIONAL SEMICONDUCTOR CORPORATION (″NATIONAL″) PRODUCTS. NATIONAL MAKES NO REPRESENTATIONS OR WARRANTIES WITH RESPECT TO THE ACCURACY OR COMPLETENESS OF THE CONTENTS OF THIS PUBLICATION AND RESERVES THE RIGHT TO MAKE CHANGES TO SPECIFICATIONS AND PRODUCT DESCRIPTIONS AT ANY TIME WITHOUT NOTICE. NO LICENSE, WHETHER EXPRESS, IMPLIED, ARISING BY ESTOPPEL OR OTHERWISE, TO ANY INTELLECTUAL PROPERTY RIGHTS IS GRANTED BY THIS DOCUMENT. TESTING AND OTHER QUALITY CONTROLS ARE USED TO THE EXTENT NATIONAL DEEMS NECESSARY TO SUPPORT NATIONAL’S PRODUCT WARRANTY. EXCEPT WHERE MANDATED BY GOVERNMENT REQUIREMENTS, TESTING OF ALL PARAMETERS OF EACH PRODUCT IS NOT NECESSARILY PERFORMED. NATIONAL ASSUMES NO LIABILITY FOR APPLICATIONS ASSISTANCE OR BUYER PRODUCT DESIGN. BUYERS ARE RESPONSIBLE FOR THEIR PRODUCTS AND APPLICATIONS USING NATIONAL COMPONENTS. PRIOR TO USING OR DISTRIBUTING ANY PRODUCTS THAT INCLUDE NATIONAL COMPONENTS, BUYERS SHOULD PROVIDE ADEQUATE DESIGN, TESTING AND OPERATING SAFEGUARDS. EXCEPT AS PROVIDED IN NATIONAL’S TERMS AND CONDITIONS OF SALE FOR SUCH PRODUCTS, NATIONAL ASSUMES NO LIABILITY WHATSOEVER, AND NATIONAL DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY RELATING TO THE SALE AND/OR USE OF NATIONAL PRODUCTS INCLUDING LIABILITY OR WARRANTIES RELATING TO FITNESS FOR A PARTICULAR PURPOSE, MERCHANTABILITY, OR INFRINGEMENT OF ANY PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY RIGHT. LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS PRIOR WRITTEN APPROVAL OF THE CHIEF EXECUTIVE OFFICER AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION.As used herein: Life support devices or systems are devices which (a) are intended for surgical implant into the body, or (b) support or sustain life and whose failure to perform when properly used in accordance with instructions for use provided in the labeling can be reasonably expected to result in a significant injury to the user. A critical component is any component in a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system or to affect its safety or effectiveness. National Semiconductor and the National Semiconductor logo are trademarks or registered trademarks of National Semiconductor Corporation. All other brand or product names may be trademarks or registered trademarks of their respective holders. Copyright © 2006 National Semiconductor Corporation. For the most current product information visit us at www.national.com. National Semiconductor Americas Customer Support Center Email: new.feedback@nsc.com Tel: 1-800-272-9959 National Semiconductor Europe Customer Support Center Fax: +49 (0) 180-530 85 86 Email: europe.support@nsc.com Deutsch Tel: +49 (0) 69 9508 6208 English Tel: +44 (0) 870 24 0 2171 Français Tel: +33 (0) 1 41 91 8790 National Semiconductor Asia Pacific Customer Support Center Email: ap.support@nsc.com National Semiconductor Japan Customer Support Center Fax: 81-3-5639-7507 Email: jpn.feedback@nsc.com Tel: 81-3-5639-7560 www.national.com LM2422TE 220V Monolithic Triple Channel 30 MHz CRT DTV Driver