In data sheets and application notes which still contain NXP or Philips Semiconductors references, use the references to Nexperia, as shown below.

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Marilynn Rodgers
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1 Important notice Dear Customer, On 7 February 2017 the former NXP Standard Product business became a new company with the tradename Nexperia. Nexperia is an industry leading supplier of Discrete, Logic and PowerMOS semiconductors with its focus on the automotive, industrial, computing, consumer and wearable application markets In data sheets and application notes which still contain NXP or Philips Semiconductors references, use the references to Nexperia, as shown below. Instead of or use Instead of sales.addresses@ or sales.addresses@ use salesaddresses@nexperia.com ( ) Replace the copyright notice at the bottom of each page or elsewhere in the document, depending on the version, as shown below: - NXP N.V. (year). All rights reserved or Koninklijke Philips Electronics N.V. (year). All rights reserved Should be replaced with: - Nexperia B.V. (year). All rights reserved. If you have any questions related to the data sheet, please contact our nearest sales office via or telephone (details via salesaddresses@nexperia.com). Thank you for your cooperation and understanding, Kind regards, Team Nexperia

2 Application Note Panoramic view circuit J.J.M. Hulshof Product Concept & Application Laboratory Eindhoven, the Netherlands. Keywords Panoramic view Wide-screen Horizontal deflection S-correction Report No : Date : Pages : 2

3 Summary: This application note is a short description of the panoramic view mode for wide-screen tubes. This mode allows a hardware switch-over to a different horizontal S-correction, which can be used to display pictures with a 4:3 aspect ratio on a wide-screen (16:9) tube. The result is screen filling picture with reasonably linearity in the centre area and an increasingly expanded picture at the left and right hand side of the screen. With a slightly reduced horizontal scan amplitude and a slightly increased vertical scan amplitude, this mode is generally accepted as a reasonable compromise for displaying 4:3 pictures on a 16:9 picture tube.

4 -1- Panoramic view circuit Technical description The circuit diagram on the next page shows a complete horizontal output stage, optimised for the Philips 16kHz wide-screen tubes. This principle is also valid for different frequencies. For a linear picture the 330n ORIGINAL S-CORRECTION CAPACITOR 330n PANORAMIC VIEW CIRCUIT BUK B BZX 79 C15 470k 22n 148V MPSA V=LINEAR H-SCAN 0-0.5V=PANORAMA MODE digital control command must be a logic "1". The collector voltage of the MPSA42 will be low. The gate source voltage of the power MOS FET will be approximately -0.6V (FET switch open) and only one S-correction capacitor is active. A logic "0" control will make the collector voltage of the MPSA42 high, the MOS-FET will be switched on and the second S-correction capacitor is activated. The gate-source voltage is filtered with a very long time constant, to block the high level line frequent signal. The drain-source resistor is added to pre charge the second S-correction capacitor. This will prevent damage of the power MOS FET during switch on. Application hints 1 In the panoramic mode some horizontal under-scan and vertical over-scan may be attractive. In a set with I²C bus, the geometry settings can be switched simultaneously with the S-correction capacitor. The value of the switched S-correction capacitor and the geometry settings can be chosen for the best visual result. 2 Philips wide-screen tubes do not need modulated S-correction. Using the simple diode modulator configuration will save costs, improve the performance and reduce power dissipation (especially in the line output transformer). 3 A larger S-correction capacitor will result in a reduced horizontal scan amplitude. For full horizontal scan in the panoramic view mode, it may be necessary to increase the scan voltage somewhat. If the collector voltage of the switching transistor (BU2508A(F)) becomes too high, a tap on the line output transformer can be used, or the anode voltage (EHT) can be slightly reduced.

5 -2- Circuit diagram +148V 100u 160V BAV21 100n k H-DRIVE 1K WIDE-SCREEN HORIZONTAL OUTPUT STAGE WITH PANORAMIC VIEW MODE GIVEN VALUES REFER TO THE 16kHz 28" WIDESCREEN TUBES : W67EWS001X01 & W67EWS001X LINE OUTPUT TRANSFORMER EHT FOCUS VG2 AUX. SUPPLIES 1K PR01 330p 1K5 PR03 1K5 AT4043 /87A 5uH 0E68 AC04 AT2077/34 BU 2508A 9n1 BY228 AT4042 /08A Lh=1.48mH 330n 330n BAV21 4u7 160V BZX 79 C15 BUK B 470k 22n MPSA42 2x BYD33D BSN n3 PCALE 28 JANUARY 1994 J.H. 27n BYW95B AT4043/68 520uH 3u3 63V PR02 EW DRIVE PANORAMIC VIEW CIRCUIT 2-12V=LINEAR H-SCAN 0-0.5V=PANORAMA MODE

Brief Description of Circuit Functions. The brief ckt. description of V20 107E5 17 Monitor

Exhibit 4 Brief Description of Circuit Functions The brief ckt. description of V20 107E5 17 Monitor 0. Functional Block Diagram 1. General Description 2. Description of Circuit Diagram A. Power Supply