YAMAR DC-Line Attenuator E lec tro n ics L td Operation Manual 1 General The DC-Line attenuator is used for testing battery power line communication performance. The attenuator attenuates the modulated signal over the battery power lines (DC-Lines) without attenuating the DC voltage. The attenuator has two BNC connectors to output the AC signals in both sides of the attenuator. Figure 1 - The DC-Line Attenuator 2 Principles of operation The DC-Line attenuator attenuates the AC component of the modulated signal on the DC, while, letting the DC component unaffected. This principle of the DC-Line attenuator is presented on figure 2. The user can select any attenuation level between 0 to 61 dB using the switches (20, 20, 10, 5, 3, 2, 1 dB). DC- DC-IN DC-OUT2 AC-OUT2 AC- ATTENUATOR Figure 2 - Block diagram Schematics of the DC-Line Attenuator ©206-2011 YAMAR Electronics Ltd. 1 Shimon Hatarsi Tel Aviv, Israel. Tel (972) 3 5445294 Fax (972) 3 5445279 DC-LINE Attenuator011.doc www.yamar.com 3 Operation Set the external power supply voltage to the specified voltage of the devices under test. Connect the DC power supply to DC-IN connector. Connect the devices under test to DC-OUT1 and DC-OUT2. The modulated AC signal over the power line from Device 1 to Device 2 and vice versa will be attenuated according to the attenuator setting. Figure 3 presents a typical application of communication between a reference DCLIN message generator and a DC-LIN evaluation board. By changing the attenuation values, the communication performance can be measured. DC Power Supply DC Out DC In DC Out AC Out1 DC-BUS EVB Under Test 1 AC Out2 2 Reference DC-BUS Message Generator 3 5 10 20 20 DC-LINE ATTENUATOR Figure 3 - Typical PLC measurement setup 4 Specifications Attenuation: Max Operating voltage: Max Operating current: Frequency range: YAMAR Electronics Ltd. 0-61 40 1 1.5 - 15 dB Volt Amp MHz 2 DC-LINE Attenuator011.doc Rev 1.0 Shimon Hatarsi Tel Aviv, Israel. Tel (972) 3 5445294 Fax (972) 3 5445279 www.yamar.com