LTC3634

Demonstration circuit 1839A is a dual output regulator focused specifically for DDR memory power applications. It is built based on the LTC3634EFE (TSSOP-28E package), a high voltage dual channel, controlled on-time monolithic synchronous buck regulator. The DC1839A has an input voltage range of 3.6V to 15V. demo board's output voltage of the first channel, V_DDQ, has three fixed voltage settings; 1.5V, 1.8V, and 2.5V, and is capable of delivering up to ±3A of output current. The second channel, V_TT, is set to regulate to half the voltage on the VDDQIN pin, which can be either the channel 1 output or an external reference voltage. It can also source or sink a maximum of 3A. The LTC3634 also provides a ±10mA buffered output, VTTR, which is half of VDDQIN and is used to provide the reference voltage needed for DDR applications.

Demonstration circuit DC1708A is a dual-output regulator focused specifically for DDR memory power applications. It is built based on the LTC3634, a high voltage dualchannel, controlled on-time monolithic synchronous buck regulator. The DC1708A has an input voltage range of 3.6V to 15V. The output voltage of the first channel, V_DDQ, of the DC1708A has three fixed voltage settings: 1.5V, 1.8V and 2.5V, and is capable of delivering up to 3A of output current. The second channel, V_TT, is set to regulate to half the voltage on the VDDQIN pin, which can be either the channel 1 output or an external reference voltage. It can source or sink a maximum of 3A of output current. The LTC3634 also provides a 10mA buffered output of half VDDQIN – VTTR, which is used to provide the reference voltage needed for DDR applications. With the use of a timing resistor, the DC1708A can have its operating frequency programmed from 500kHz to 4MHz. Additionally the DC1708A can be easily synchronized to an external clock, due to an internal phase-locked loop, within this same frequency range. The DC1708A VDDQ output can operate in either Burst Mode^® operation or forced continuous mode. In Burst Mode operation, which is the preferred mode of low load current operation, the DC supply current is typically only 1.3mA (both channels) at no load (sleep mode), and less than 15µA in shutdown. In Burst Mode operation or continuous mode operation, the DC1708A is a very efficient circuit at high load currents: over 80% for either channel. The LTC3634 is also capable of 90° or 180° out-of-phase operation, and can allow its output to track an external voltage, either coincidentally or ratiometrically. The LTC3634 comes in a 28-pin QFN package, featuring an exposed pad on the bottom-side of the IC for better thermal performance. All of these features make the DC1708A an ideal circuit for powering DDR memory applications.

ADI Key Power Management Features for Versal ACAP XCXM1802 for Optimized Efficiency

• Proposed Solution implements new LTC3887-1/LTC7051 combo
• LTC3887-1 is a PMBus 2-phase, 2 loop, current mode controller. PMBus commands allow Vin, Vout, current, temperature, and fault status read back.
• LTC7051 is new Silent Switcher 2 ADI MOS capable of delivering increased DC load while switching at higher frequencies. Increased DC load allows for decreased phase count and higher current density. Increased Fsw allows for increase bandwidth and excellent transient response.
• LTC3636 is dual 6A, controlled on-time current mode monolithic (integrated FETs). Provides high performance compact solution for auxiliary rails.
• LTC3634 is a single chip solution for DDR rails providing VDD, VTT, and Vref in a monolithic solution.
• LTC3634 is a single chip solution for DDR rails providing VDD, VTT, and Vref in a monolithic solution.

ADI Key Power Management Features for Versal PRIME XCXM1802 for Minimum Rails / PL Performance

• Proposed Solution implements new LTC3887-1/LTC7051 combo
• LTC3887-1 is a PMBus 2-phase, 2 loop, current mode controller. PMBus commands allow Vin, Vout, current, temperature, and fault status read back.
• LTC7051 is new Silent Switcher 2 ADI MOS capable of delivering increased DC load while switching at higher frequencies. Increased DC load allows for decreased phase count and higher current density. Increased Fsw allows for increase bandwidth and excellent transient response.
• LTC3636 is dual 6A, controlled on-time current mode monolithic (integrated FETs). Provides high performance compact solution for auxiliary rails.
• LT8607 is a compact, high efficiency, high speed 750mA synchronous monolithic.
• LTC3634 is a single chip solution for DDR rails providing VDD, VTT, and Vref in a monolithic solution.

ADI Key Power Management Features for Versal ACAP XCXM1802 for Mid to High Voltage

• Proposed Solution implements new LTC3887-1/LTC7051 combo
• LTC3887-1 is a PMBus 2-phase, 2 loop, current mode controller. PMBus commands allow Vin, Vout, current, temperature, and fault status read back.
• LTC7051 is new Silent Switcher 2 ADI MOS capable of delivering increased DC load while switching at higher frequencies. Increased DC load allows for decreased phase count and higher current density. Increased Fsw allows for increase bandwidth and excellent transient response.
• LTC3636 is dual 6A, controlled on-time current mode monolithic (integrated FETs). Provides high performance compact solution for auxiliary rails.
• LTC3644 is a quad 1.25A output, high efficiency synchronous monolithic capable of switching up to 2.25MHz.
• LTC3634 is a single chip solution for DDR rails providing VDD, VTT, and Vref in a monolithic solution.

ADI Key Power Management Features for Versal PRIME XCXM1802 for Low Voltage

• Proposed Solution implements new LTC3887-1/LTC7051 combo
• LTC3887-1 is a PMBus 2-phase, 2 loop, current mode controller. PMBus commands allow Vin, Vout, current, temperature, and fault status read back.
• LTC7051 is new Silent Switcher 2 ADI MOS capable of delivering increased DC load while switching at higher frequencies. Increased DC load allows for decreased phase count and higher current density. Increased Fsw allows for increase bandwidth and excellent transient response.
• LTC3636 is dual 6A, controlled on-time current mode monolithic (integrated FETs). Provides high performance compact solution for auxiliary rails.
• LTC3644 is a quad 1.25A output, high efficiency synchronous monolithic capable of switching up to 2.25MHz.
• LTC3634 is a single chip solution for DDR rails providing VDD, VTT, and Vref in a monolithic solution.

The ADI Versal AI Core Power Reference Design Board has been tested and proven to power the key rails for the Xilinx Versal AI Core ACAP series. Using a PMBUs Multi Phase DC/DC controller coupled with ADI SilentMOS (ADI version of DrMOS) to deliver up to 240A of output current.

The ADI LTC3888-1 is an 8 Phase PMBUs DC/DC controller that is coupled with the LTC7051 ADI SilentMOS to provide a flexible and scalable design that can be tailored as needed for both higher and lower power applications by adding or subtracting the LTC7051 ADI SilentMOS.

Request schematic for ADI power used on the board.

Contact ADI if you have questions about the ADI power management solutions used on this board.

Versal™ AI Prime series solves a broad range of industry-specific problems with performance and flexibility. Some of these cases include storage acceleration, data center network acceleration, 5G xHaul and Passive optical networks.

Analog Devices, Inc. supports Versal AI power management by offering a full comprehensive solution inclusive of their next generation PM Bus Controller and ADI’s DrMOS. The Versal Demonstration boards support Mid-Voltage and High-Voltage applications without power management. For a complete list power designs and use cases Versal AI Prime please contact your local FAE.

Key Featrues Include

• LTC3887-1 is a PMBus dual phase, current mode controller with ADI’s DrMOS. PMBus commands allow Vin, Vout, current, temperature, and fault status read back.
• LTC7051 is a new Silent Switcher 2 ADI’s DrMOS capable of delivering increased DC load while switching at higher frequencies.  Increased DC load allows for decreased phase count and higher current density.  Increased Fsw allows for increase bandwidth and excellent transient response..
• LTC3636 is a dual 6A, controlled on-time current mode monolithic (integrated FETs).  Provides high performance compact solution for auxiliary rails.
• LT8607 is a compact, high efficiency, high speed 750mA synchronous monolithic.
• LTC3634 is a single chip solution for DDR rails providing VDD, VTT, and Vref in a monolithic solution.