This example reference circuit provides all the power-supply rails and power sequencing necessary to power Xilinx® ZU9/15 Wireless Backhaul power supplies. The module accepts 12V input voltage and generates seven power. The V_CCPINT output is set to 0.85V with 3A output-current capability by using the MAX15303 step-down switching regulator. The V_CCINT output is set to 0.72V with 12A output current capability by using the MAX20730 PMBus^™ step-down switching regulator. Both V_MGTAVCC and V_MGTAVTT output voltages are generated from the MAX17509 dual step-down regulator. V_MGTAVCC is set to 0.9V with 2A capability and the V_MGTAVTT is set to 1.2V with 2A current capability. Both V_MGTAVCC and V_MGTAVTT output voltages have less than 10mV output ripple, which meet the ripple requirements. Another MAX17509 IC generates the V_AUX and V_MGTAVCCAUX output voltages. VAUX is capable of delivering 1A at 1.8V and V_MGTAVCCAUX is capable of delivering 1A at 1.8V. The MAX17541G generates the V_CCOPIO output voltage. V_CCOPIO is capable of delivering 0.5A at 3.3V.

The power module provides extremely compact, high-efficiency power solutions with high-precision output voltages and excellent transient response.

Features

• InTune^™ Digital PoL SMPS MAX15303
  
  
• 600kHz Switching Frequency
• 12V Input Voltage
• 0.85V at 3A (VCCPINT)


• Integrated Buck Regulator SMPS MAX20730
  
  
• 400kHz Switching Frequency
• 12V Input Voltage
• 0.72V at 12A (V_CCINT), 10mV ripple


• Dual Buck Regulator SMPS MAX17509
  
  
• 1MHz Switching Frequency
• 12V Input Voltage
• 0.9V at 2A (V_MGTAVCC), 10mV ripple
• 1.2V at 2A (V_MGTAVTT), 10mV ripple


• Dual Buck Regulator SMPS MAX17509
  
  
• 1MHz Switching Frequency
• 12V Input Voltage
• 1.8V at 1A (V_AUX)
• 1.8V at 1A (V_MGTAVCCAUX)


• Buck Regulator SMPS MAX17541G
  
  
• 600kHz Switching Frequency
• 12V Input Voltage
• 3.3V at 0.5A (V_CCOPIO)

Detailed Description

V_CCINT (0.72V) Output:

The MAX20730 step-down regulator accepts 12V input and generates 0.72V output with 12A current capability. The switching frequency is set to 400kHz. The output voltage is set by resistors R104 (1.27k) and R105 (11.5k). The output voltage can be changed by changing R104 and R105. Refer to the Output-Voltage Setting section of the MAX20730 data sheet. The output voltage, switching frequency, and current limit can also be monitored and programmed using a PMBus serial connection using Maxim's PowerTool™ software. This gives the user the ability to margin their designs during operation.

This regulator includes overcurrent (OCP) and overtemperature protection (OTP). It has 0.2% load regulation at full load and excellent transient response.

V_CCINT Switching Frequency

V_CCINT Transient Response (1A to 10A load)

V_CCINT Output Ripple (12A load)

V_CCPINT (0.85V) Output

The MAX15303 step-down regulator accepts 12V input and generates 0.85V output with 3A current capability. The switching frequency is set to 600kHz. The output voltage is set by resistor R203 (9.53k). The output voltage can be changed by changing R203. Refer to the Output-Voltage Setting section of the MAX15303 data sheet. The output voltage, switching frequency, and current limit can also be monitored and programmed using a PMBus serial connection using Maxim’s PowerTool software. This gives the user the ability to margin their designs during operation. This regulator includes overcurrent (OCP) and overtemperature protection (OTP). It has 0.12% load regulation at full load and excellent transient response.

V_CCPINT Switching Frequency

V_CCPINT Transient Response (1A to 3A load)

V_CCPINT Output Ripple (3A load)

V_MGTAVCC (0.9V) and V_MGTAVTT (1.2V) Outputs:

The MAX17509 dual step-down regulator accepts 12V input and generates 0.9V and 1.2V outputs with 2A current capability for each output. The switching frequency is set to 1MHz. The 0.9V output voltage is set by resistors R310 (115k) and R311 (4.75k). The 1.2V output voltage is set by resistors R314 (6.81k) and R315 (75k). Both outputs can be changed by changing the feedback resistors. Refer to the Output-Voltage Setting section of the MAX17509 data sheet. The MAX17509 includes overcurrent (OCP) and overtemperature protection (OTP). It has excellent load regulation at full load and transient response. Both outputs have better than 10mV output ripple.

V_MGTAVCC Switching Frequency

V_MGTAVCC Transient Response (1A to 2A load)

V_MGTAVCC Output Ripple (2A load)

V_MGTAVTT Switching Frequency

V_MGTAVTT Transient Response (1A to 2A load)

V_MGTAVTT Output Ripple (2A load)

V_AUX (1.8V) and V_MGTAVCCAUX (1.8V) Outputs:

The MAX17509 dual step-down regulator accepts 12V input and generates 1.8V and 1.8V outputs with 1A current capability for the 1.8V and 1A current capability for the 1.8V output. The switching frequency is set to 1MHz. The 1.8V output voltage is set by resistors R410 (40.2k) and R411 (11.8k). The 1.8V output voltage is set by resistors R414 (11.8k) and R415 (40.2k). Both outputs can be changed by changing the feedback resistors. Refer to the Output-Voltage Setting section of the MAX17509 data sheet. The MAX17509 includes overcurrent (OCP) and overtemperature protection (OTP). It has excellent load regulation at full load and transient response. Both outputs have better than 10mV output ripple.

V_AUX Switching Frequency

V_AUX Transient Response (0A to 1A load)

V_AUX Output Ripple (1A load)

V_MGTAVCCAUX Switching Frequency

V_MGTAVCCAUX Transient (0A to 1A load)

V_MGTAVCCAUX Output Ripple (1A load)

V_CCOPIO (3.3V) Output

The MAX17541G step-down regulator accepts 12V input and generates 3.3V output with 0.5A current capability. The switching frequency is set to 600kHz. The output voltage is set by resistors R704 (48.7k) and R705 (18.2k). The output voltage can be changed by changing R704 and R705. Refer to the Output-Voltage Setting section of the MAX17541G data sheet . The MAX17541G includes overcurrent (OCP) and overtemperature protection (OTP). It has 0.1% load regulation at full load and excellent transient response.

V_CCOPIO Switching Frequency

V_CCOPIO Transient Response (0A to 0.5A load)

Power Sequencing

Power Sequencing has een achieved by using the power good and enable signals to sequence the output voltages. Output voltages V_CCINT, V_CCPINT and V_MGTAVCC power up first, followed by V_MGTAVTT, V_AUX and V_MGTAVCCAUX and V_CCOPIO. An I2C, SMBus, or PMBus sequencer such as the MAX34440 can also be used for voltage monitoring and power sequencing.

_{InTune is a trademark of Maxim Integrated Products, Inc.}

_{PMBus is a trademark of SMIF, Inc.}

_{PowerTool is a trademark of Maxim Integrated Products, Inc.}

_{Xilinx is a registered trademark and registered service mark of Xilinx, Inc.}