Click here for production status of specific part numbers. Evaluates: MAX20328/ MAX20328A Evaluation Kit MAX20328A/MAX20328B General Description Quick Start The MAX20328A evaluation kit (EV kit) is a fully assem- Required Equipment bled and tested circuit for evaluating the MAX20328/ The following equipment is required to verify the basic MAX20328A/MAX20328B MUX switch for USB-C audio functionality of this EV kit: adapter applications. The device features automatic MIC- 5V capable power supply GND orientation and headphone impedance detection, 2 Beyond-the-Rails signal capability, and surge protec- Host device with I C communication support tion on pins attached to the USB-C connector. This EV DMM or continuity tester kit enables fast and easy evaluation of the MAX20328/ MAX20328A/MAX20328B switches in USB-C audio appli- Optional Equipment cations. The following equipment can be used for more complete testing of this EV kit: The EV kit is populated with MAX20328A. The MAX20328, MAX20328A, and MAX20328B are pin-to-pin and register USB Flash drive or other device with a USB-A male compatible. Users can install their own MAX20328 for connector evaluation. USB A-to-B cable USB C cable Features Automatic MIC/GND Orientation Detection TRRS 3.5mm audio cable MIC Line Bias Check Safeguards Against Shorting TRRS 3.5mm audio device with 3.5mm to USB-C MIC to GND passive adapter 3.5mm Audio Jack for Testing with Audio Signals Procedure Onboard USB Receptacles for Passing and The EV kit is fully assembled and tested. Follow the steps Measuring Data Signals below to verify board operation: Proven PCB Layout 1) Verify the positions of the configuration resistor pairs Fully Assembled and Tested R1 and R2, R4 and R5, and R6 and R8. a) For evaluating MAX20328, R1, R4, and R6 should be installed. b) For evaluating MAX20328A/MAX20328B, R2, Ordering Information appears at end of data sheet. R5, and R8 should be installed. 2) Verify shunts are installed on jumpers JU1 and on JU3 in the 1-2 position. JU3 selects the source of the V supply. CC 3) Connect the positive lead of a 2.7 to 5V power supply to TP12 and the negative lead to TP14, then safely turn on the supply. 2 4) Connect SCL of the I C device to TP16 and SDA to TP17 or use the 40-pin connector. 2 5) Read register 0x00 using the I C read address 0x2B. If the data read matches the DEVICE ID value of the installed device (Table 5 of the MAX20328/ MAX20328A/MAX20328B data sheet), the EV kit is Beyond-the-Rails is a trademark of Maxim Integrated Products, Inc. configured correctly. 319-100192 Rev 1 1/20Evaluates: MAX20328/ MAX20328A Evaluation Kit MAX20328A/MAX20328B To test automatic audio headset detection and switch Hardware Connectors configuration, use the following procedure: The MAX20328A EV kit contains several USB connectors 1) After establishing communication with the EV kit and a 3.5mm audio jack to conveniently check the device, verify that automatic headset detection is functionality of different signal paths. enabled. Enable it if needed. USB Connectors 2) Supply an audio signal to the 3.5mm jack J7 on the A USB-C female connector connects to the top- (DP T, EV kit. DM T) and bottom-side (DP B, DM B) D+/D- data 3) Insert a TRRS headset with USB-C passive adapter lines, SBU lines, and the CC2 pin to the MAX20328/ (this will not work for active adapters) and verify the MAX20328A/MAX20328B as they would in a typical appli- audio signal is routed to the headset. cation. Alternatively, two USB-B female connectors are also available to provide these signals independently. J2 Detailed Description of Hardware connects to DP B and DM B, and J4 connects to DP T The MAX20328A EV kit is a fully assembled and tested and DM T. PCB for evaluating the MAX20328, MAX20328A, and Two USB-A female connectors allow for testing data MAX20328B USB-C audio MUX switches. Although the transfer to a USB flashdrive or similar device with a MAX20328, MAX20328A, and MAX20328B have slightly USB-A male connector. J1 connects to the bottom side different features, the same hardware can be used to data pins and J6 connects to the top side data pins. evaluate both devices. By installing combinations of 3.5mm Audio Jack 0 resistors, the signals will be routed correctly for the selected device. The EV kit also includes a 3.5mm jack for evaluating the audio signal routing action. The TRRS jack J7 simplifies injecting an audio signal into the EV kit. When a 3.5mm audio headset is detected on the USB-C input by means of a passive adapter, the signal coming into J7 will be routed to the USB-C connector and the headset. Table 1. Jumper Configurations JUMPER SHUNT POSITION DESCRIPTION Installed* Connects V of the device to the EV kit supply. CC JU1 Not Installed V of the device disconnected from EV kit supply. CC Installed Attaches a 3.92k pullup resistor to V on INT of the MAX20328A/MAX20328B. CC JU2 Not Installed* No pullup on MAX20328A/MAX20328B INT pin. 1-2* Connects EV kit supply to TP12 for an external supply voltage. JU3 2-3 Connects EV kit supply to the 3.3V line of the 40-pin connector. Installed Connects a 3.92k pullup resistor from SCL to the 3.3V line of the 40-pin connector. JU4 Not Installed* No pullup on SCL to 3.3V line. Installed Connects a 3.92k pullup resistor from SDA to the 3.3V line of the 40-pin connector. JU5 Not Installed* No pullup on SDA to 3.3V line. 1-2* Ties U1 CC pin to V through a 10k pullup resistor. Leave open or shunt 1-2 to use J3 CC. CC JU6 2-3 Ties U1 CC pin to ground. Leave open or shunt 1-2 to use J3 CC. Installed* J3 CC is connected to U1 CC and pulled to voltage selected by JU6. JU7 Not Installed U1 CC is floating or tied to voltage selected by JU6. Installed* Connects GSNS L (MAX20328) or GSNS (MAX20328A/MAX20328B) to AGND. JU8 Not Installed GSNS L (MAX20328) or GSNS (MAX20328A/MAX20328B) not connected to AGND. Installed Connects GSNS R (MAX20328) to AGND. JU9 Not Installed* Connects GSNS R (MAX20328) to AGND. *Default position Maxim Integrated 2 www.maximintegrated.com