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KX-TG6421BX/KX-TGA641BX 1.2. Circuit Operation (Base Unit) 1.2.1. Outline Base Unit consists of the following ICs as shown in Block Diagram (Base Unit) (P.2). • DECT BBIC (Base Band IC): IC7 - Handling all the audio, signal and data processing needed in a DECT base unit...
KX-TG6421BX/KX-TGA641BX 1.2.2. Power Supply Circuit The power is supplied to the DECT BBIC, RF Module, EEPROM and Charge Contact from AC Adaptor (+6.5 V) as shown in Fig.101. The power supply is as follows; • DECT BBIC (IC7): DC Jack (+6.5 V) →D1→ IC1 → IC7 DC Jack (+6.5 V) →D1→...
KX-TG6421BX/KX-TGA641BX 1.2.3. Telephone Line Interface <Function> • Bell signal detection • Clip signal detection • ON/OFF hook circuit Bell & Clip (: Calling Line Identification Presentation: Caller ID) signal detection: In the standby mode, Q3 is open to cut the DC loop current and decrease the ring load.
KX-TG6421BX/KX-TGA641BX 1.4. Circuit Operation (Handset) 1.4.1. Outline Handset consists of the following ICs as shown in Block Diagram (Handset) (P.6). • DECT BBIC (Base Band IC): IC1 - All data signals (forming/analyzing ACK or CMD signal) - All interfaces (ex: Key, Detector Circuit, Charge, DC/DC Converter, EEPROM, LCD, RF Power Amp.)
KX-TG6421BX/KX-TGA641BX 2 Schematic Diagram 2.1. For Schematic Diagram 2.1.1. Base Unit (Schematic Diagram (Base Unit)) Notes: 1. DC voltage measurements are taken with voltmeter from the negative voltage line. 2. The schematic diagrams may be modified at any time with the development of new technology.
KX-TG6421BX/KX-TGA641BX 2.2. Schematic Diagram (Base Unit) ANT1_TP ANT2_TP ANT_1 ANT_2 C851 C853 W 0.15mm W 0.15mm L 22+/-4mm L 22+/-4mm Beep 1st or 4th layer 1st or 4th layer Bell signal DA802 *R86 W 0.15mm L 22+/-4mm 1st or 4th layer W 0.15mm...
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KX-TG6421BX/KX-TGA641BX W 0.15mm L 20+/-2mm 3rd layer R807 RXON L801 C827 TP_ANT1 RX_RF C826 RF_RXn *C859 C803 1.5p DA801 RF_RXp W 0.125mm L 7.6mm CP+3.0V Gap 0.125mm W 0.15mm W 0.15mm 1st layer L 5.0mm L 5.0mm 1st layer 1st layer C172 K0.1u...
KX-TG6421BX/KX-TGA641BX 4 Exploded View and Replacement Parts List 4.1. Replacement Part List Safety Ref. Part No. Part Name & Description Remarks 1. RTL (Retention Time Limited) B1ABCE000009 TRANSISTOR(SI) Note: B1ACGP000007 TRANSISTOR(SI) PQVTBF822T7 TRANSISTOR(SI) The “RTL” marking indicates that its Retention Time is...
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KX-TG6421BX/KX-TGA641BX Safety Ref. Part No. Part Name & Description Remarks Safety Ref. Part No. Part Name & Description Remarks ERJ1TYJ3R9U C137 ECUE1H100DCQ 10p ERJ2GEJ101 C141 ECJ0EB0J224K 0.22 ERJ2GEJ102 C145 ECUE1H100DCQ 10p ERJ2GEJ103 C146 ECUE1H100DCQ 10p ERJ2GEJ332 3.3k C147 ECUE1H100DCQ 10p...
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KX-TG6421BX/KX-TGA641BX Safety Ref. Part No. Part Name & Description Remarks Safety Ref. Part No. Part Name & Description Remarks (DIODES) C834 F1G1HR50A480 0.5p LED901 PQVDBR1111C LED C859 F1G1H3R0A480 3p LED902 PQVDBR1111C LED C860 ECUE1H100DCQ 10p C861 F1G1H3R0A480 3p 4.1.2. Handset C862 F1G1HR70A480 0.7p...
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