Analog Devices LT83401 | Demoboard EVAL-LT83401-AZ

Beschreibung

The EVAL-LT83401-AZ and EVAL-LT83402-AZ (abbreviated as EVAL-LT83401/2-AZ) demonstration boards are 42V, 1A, and 2.5A synchronous Silent Switcher® 3 step-down regulators with ultra-low noise, high efficiency, and power density, featuring the LT83401 and LT83402 (abbreviated as LT83401/2), respectively. The input voltage range of the EVAL-LT83401/2-AZ is 4.8V to 42V. The default demo board setting is 3.3V output with a maximum 1A/2.5A DC output current. The LT83401/2 is a compact, ultra-low noise, ultra-low emission, high efficiency, and high-speed synchronous monolithic step-down switching regulator. The uniquely designed combination of the ultra-low noise reference and third-generation Silent Switcher architecture enables the LT83401/2 to achieve both high efficiency and excellent wideband noise performance. A minimum on-time of 22ns allows high VIN to low VOUT conversion at high frequency.The LT83401/2’s switching frequency can be programmed either through an external resistor (RT) or an external clock over a 300kHz to 6MHz range. The default frequency of EVAL-LT83401/2-AZ demo boards is 2MHz. The SYNC/MODE pin on the demo boards is connected to ground by default for pulse-skip mode operation. To synchronize to an external clock, move JP1 to SYNC and apply the external clock to the SYNC terminal. Select the forced continuous mode (FCM) by moving the JP1 shunt, respectively. Figure 1 and Figure 2 in the User Guide show the efficiency of the EVAL-LT83401/2-AZ at the 12V and 24V inputs in FCM operation (input from VIN terminal). Figure 3 shows the temperature rise of the LT83401 on the EVAL-LT83401-AZ demo board under 12V and 24V input voltage conditions across the full load range. Figure 4 shows the temperature rise of the LT83402 on the EVAL-LT83402-AZ demo board under 12V and 24V input voltage conditions across the full load range. The case temperature rise was measured with the following reference points: The peak IC case temperature and a point on the board, marked with a red ‘X’ as shown in the thermal images Figure 12 and Figure 13 in the User Guide.

Eigenschaften

TheEVAL-LT83401-AZandEVAL-LT83402-AZ(abbreviated as EVAL-LT83401/2-AZ) demonstrationboards are 42V, 1A, and 2.5A synchronous SilentSwitcher® 3 step-down regulators with ultra-low noise, highefficiency, and power density, featuring the LT83401 andLT83402 (abbreviated as LT83401/2), respectively. Theinput voltage range of the EVAL-LT83401/2-AZ is 4.8V to42V. The default demo board setting is 3.3V output with amaximum 1A/2.5A DC output current. The LT83401/2 is acompact, ultra-low noise, ultra-low emission, highefficiency, and high-speed synchronous monolithic stepdown switching regulator. The uniquely designedcombination of the ultra-low noise reference and thirdgeneration Silent Switcher architecture enables theLT83401/2 to achieve both high efficiency and excellentwideband noise performance. A minimum on-time of 22nsallows high VIN to low VOUT conversion at high frequency.The LT83401/2’s switching frequency can be programmedeither through an external resistor (RT) or an external clockover a 300kHz to 6MHz range. The default frequency ofEVAL-LT83401/2-AZ demo boards is 2MHz. TheSYNC/MODE pin on the demo boards is connected toground by default for pulse-skip mode operation. Tosynchronize to an external clock, move JP1 to SYNC andapply the external clock to the SYNC terminal. Select theforced continuous mode (FCM) by moving the JP1 shunt,respectively. Figure 1 and Figure 2 show the efficiency ofthe EVAL-LT83401/2-AZ at the 12V and 24V inputs inFCM operation (input from VIN terminal). Figure 3 showsthe temperature rise of the LT83401 on the EVALLT83401-AZ demo board under 12V and 24V input voltageconditions across the full load range. Figure 4 shows thetemperature rise of the LT83402 on the EVAL-LT83402AZ demo board under 12V and 24V input voltageconditions across the full load range. The caseRev. 1temperature rise was measured with the followingreference points: The peak IC case temperature and apoint on the board, marked with a red ‘X’ as shown in thethermal images Figure 12 and Figure 13.Both demo boards have an electromagnetic interference(EMI) filter installed by default, with VIN_EMI as its inputterminal. The EMI performance of the EVAL-LT83401/2-AZ is shown in Figure 5 and Figure 6. The red lines in thesefigures represent the CISPR25 Class 5 limits, indicatingthat both the EVAL-LT83401-AZ and EVAL-LT83402-AZmeet the CISPR25 standard.The LT83401/2 also feature ultra-low noise across a widefrequency range. Figure 7 shows the noise spectral densityof the LT83402 on a default EVAL-LT83402-AZ undervarious loads. At full load, the noise hump near 100kHzdoes not exceed 10nV/√Hz.
Figure 8 and Figure 9 show the output ripple of EVALLT83401/2-AZ boards. The transient response of theEVAL-LT83401/2-AZ demo boards is shown in Figure 10and Figure 11. Refer to the LT83401/LT83402 data sheetfor figures showing faster transient response withcorresponding modifications.TheLT83401/LT83402 data sheet provides acomprehensive description, including operational andapplication information, and serves as a valuablereference in conjunction with this user guide for the EVALLT83401/2-AZ demo boards. The LT83401/2 areassembled in 3mm x 2mm x 0.75mm LFCSP packageswith exposed ground pads for low thermal resistance. Thelayout recommendations for low EMI operation andmaximum thermal performance are available in the PCBLayout Recommendations section of the LT83401/LT83402 data sheet.

Typische Anwendungen

Weiterführende Informationen

• Datenblatt
• Produktseite des IC-Herstellers