LT8604/
LT8604C

Demonstration circuit 2867A features the LT8604C, a high efficiency 42V, 120mA synchronous step-down regulator in 12-Lead 2mm × 2mm LQFN package. The demo board is designed for 120mA at 5V output from a 5.8V to 42V input, with the switching frequency programmed at 2MHz. The wide input range allows a variety of input sources, such as automotive batteries and industrial supplies.

The LT8604C is a compact high efficiency, and high frequency synchronous monolithic step-down switching regulator, with soft-start capacitor, compensation network, BST and INTV_CC capacitors, all packed into a 2mm by 2mm package.

The switching frequency can be programmed via an oscillator resistor over a wide range from 200kHz to 2.2MHz, or sync to external clock through SYNC/MODE pin. Peak current mode control with minimum on-time of as small as 35ns allows high step-down conversion even at high frequency.

The operation mode can be configured via the SYNC/MODE pin for forced continuous mode, Burst Mode^® operation, or spread spectrum mode. While in Burst Mode operation, the current limit of the LT8604C top switch is approximately 215mA. The switching frequency will be far lower than the RT programmed frequency, and correspondingly much higher efficiency over wide loads ranges.

The low quiescent current and high efficiency in Burst Mode make it an ideal solution for applications requiring highest efficiency at very light load conditions, such as automotive housekeeping supplies, industrial sensors, flow meters, Internet of Things, and battery powered portable instruments.

The demo board 2867A has an EMI filter installed. The EMI performance of the board running in SSFM mode is shown in Figure 2 of the demo manual, where the red lines are CISPR25 Class 5 average limits. The circuit passes the average limit with a wide margin.

The LT8604/LT8604C data sheet gives a complete description of the part, operation, and application information. The data sheet must be read in conjunction with the 2867A demo manual. Contact ADI applications engineer for technical support.

Demonstration circuit EVAL-LT8604-AZ features the LT8604, a high efficiency 42V, 120mA synchronous stepdown regulator in 10-Lead 3mm × 2mm side-wettable DFN package. The demo board is designed for 120mA at 5V output from a 5.9V to 42V input, with switching frequency of 0.7MHz. The wide input range allows a variety of input sources, such as automotive batteries and industrial supplies.

The LT8604 is a compact high efficiency, and high frequency synchronous monolithic step-down switching regulator. The regulator is featured with ultralow 2.5μA quiescent current with the output in full regulation, making it an ideal solution for applications requiring highest efficiency at very light load currents, such as automotive and battery powered portable instruments.

Peak current mode control with minimum on-time of as small as 35ns allows high step-down conversion even at high frequency. The LT8604 switching frequency can be programmed via an oscillator resistor over a 200kHz to 2.2MHz range. The default frequency of the evaluation board is 700kHz.

The demo board has an EMI filter installed. The EMI performance of the board is shown on Figure 2 in the demo manual. The red line in Radiated EMI Performance is CISPR25 Class 5 peak limit. The figure shows that the circuit passes the peak limit test from 30MHz to 1GHz, with a wide margin.

The LT8604 data sheet gives a complete description of the part, operation and application information. The data sheet must be read in conjunction with the demo manual. The layout recommendations for best thermal performance are available in the data sheet Application Information section. Contact ADI applications engineer for technical support.

• LT8604C configured as an inverting buck
• V_IN: 3.2 V to 42 V
• V_OUT: resistor programmable from –0.8 V to –34 V (–5 V default voltage output)
• Maximum output current is 120 mA
• Default switching frequency: 2.0 MHz
• Adjustable switching frequency: 200 kHz to 2.2 MHz

Demonstration circuit SCP-LT8604C-IEVALZ is a high efficiency 42V, 120mA synchronous step-down regulator configured as an inverting buck topology for positive to negative DC voltage conversion.

Like all boards in the Signal Chain Power series, this board is designed to be easily plugged into other SCP boards to form a complete signal chain power system, enabling fast evaluation of low power signal chains. To evaluate this board, some universal SCP hardware is required, namely:

To properly evaluate SCP series demo boards, you will need the SCP Configurator companion software. SCP Configurator can help you choose the right board and topology for your design.

Note that the Demo Manual does not cover details important to the operation and configuration regarding the LT8604C. Please refer to the LT8604C data sheet for a complete description of the part.

• LT8604C in buck configuration
• V_IN: 3.2 V to 42 V
• V_OUT: resistor programmable from 0.8 V to 34 V (5 V default voltage output)
• Maximum output current is 120 mA
• Feedback-compatible with VIOC-control linear regulators
• Default switching frequency: 2.0 MHz
• Adjustable switching frequency: 200 kHz to 2.2 MHz

Demonstration circuit SCP-LT8604C-BEVALZ is a high efficiency 42V, 120mA synchronous step-down regulator. The wide input range also allows inversion if using the SCP-LT8604C-IEVALZ-version.

Like all boards in the Signal Chain Power series, this board is designed to be easily plugged into other SCP boards to form a complete signal chain power system, enabling fast evaluation of low power signal chains. To evaluate this board, some universal SCP hardware is required, namely:

To properly evaluate SCP series demo boards, you will need the SCP Configurator companion software. SCP Configurator can help you choose the right board and topology for your design.

Note that the Demo Manual does not cover details important to the operation and configuration regarding the LT8604C. Please refer to the LT8604C data sheet for a complete description of the part.