TI's LM74502-Q1 Evaluation module, LM74502Q1EVM, is a two-channel EVM that helps designers evaluate the operation and performance of the LM74502-Q1 in channel 1 and LM74502H-Q1 in channel 2 respectively. This evaluation module demonstrates how LM74502-Q1 drives external back-to-back connected N-channel MOSFETs to realize reverse polarity protection and load disconnect feature in case of overvoltage and undervoltage events. LM74502-Q1 has a gate drive strength of 60 μA, which makes it suitable for use in applications that need inherent inrush current control. On the other hand, LM74502H-Q1 has a faster gate drive of 11-mA peak, which makes it suitable for applications which need fast turn-on and turn-off of external MOSFET switch. With the enable pin low during the standby mode, both the external MOSFETs and controller is off and draws a very low 1 μA of current.

Key features of the EVM include:

• 12-V and 24-V automotive reverse battery protection
• Input operating range 3 V to 40 V, extendable to 65 V
• 12-V battery protection 3 V to 40 V
• 24-V battery protection 3 V to 65 V
• 5-A maximum load current with option for 10-A operation
• Switched output for power path cutoff
• Enable ON and OFF control
• Output voltage slew rate control
• LED Indication for output ON and OFF detection
• Onboard TVS protection for automotive transient immunity

• Automotive reverse battery protection
• ADAS domain controller
• Premium audio amplifier
• Camera ECU
• Head unit
• USB HUBs
• Power path protection, power mux and ORing

The LM74502-Q1EVM is configured by default for evaluating 12-V and 24-V reverse polarity protection through external back-to-back FET control, with additional abilities to configure and evaluate LM74502H-Q1 as a load switch and LM74502-Q1 as a surge stopper/transient suppressor. Also, the module enables the user to adjust and evaluate overvoltage cutoff, clamp protection and output voltage slew rate control.

Input power is applied at the terminals J1 and J5 for channel 1 and J7 and J11 for channel 2. Terminals J2 and J6, J8 and J12 provide output connection to load for channel 1 and channel 2 respectively.

Channel 1 on the LM74502-Q1EVM is populated with one set of back-to-back connected N-channel MOSFETs (Q3 and Q4 in channel 1) capable to support 5-A applications. Placeholders for parallel FETs (Q1 and Q2 in channel 1) and are provided for extending current to 10 A and can be used to validate other MOSFETs. To enable the user to evaluate load switch functionality, one FET (Q8) is populated on channel 2.

Table 2-1 lists the LM74502Q1EVM board input and output connector functionality. Table 2-2 and Table 2-3 describe the test points description and the jumper functionality of the EVM respectively.