AM437x General Purpose EVM HW User Guide


 * AM437x General Purpose Evaluation Module (TMDXEVM437x) Hardware User Guide

Ver. 1.02

= Introduction =

This document describes the hardware architecture of the AM437x Evaluation Module (EVM) (Part # TMDXEVM437X) which is based on the Texas Instruments AM437x processor. This EVM is also commonly known as the AM437x General Purpose (GP) EVM.

Description
The AM437x General Purpose EVM is a standalone test, development, and evaluation module system that enables developers to write software and develop hardware around an AM437x processor subsystem. The main elements of the AM437x subsystem are already available on the base board of the EVM which gives developers the basic resources needed for most general purpose type projects that encompass the AM437x as the main processor. Furthermore, additional, "typical" type peripherals are built into the EVM such as memory, sensors, LCD, Ethernet PHY, etc. so that prospective systems can be modeled quickly without significant additional hardware resources.

The following sections give more details regarding the EVM.

System View
The System View of the AM437x GP EVM consists the main board and the camera board. See the pictures below of the EVM.

Schematics/Design/Errata Files
Be sure to view the Errata document for important notes
 * HW Documentation - Schematics, Design Files, and other related HW Documentation

= Functional Blocks Description =

The complete AM437x General Purpose EVM is contained mostly within a single board. The GP EVM also can have a camera board (which adds a second camera module to the system) and/or wireless communication card.



Figure 3: AM437x EVM System Block Diagram

Processor
The AM437x processor is the central processor to this EVM. All the resources on the board surround the AM437x processor to provide development capabilities for hardware and software. See the AM437x datasheet and TRM for the details about the processor.

There are system configuration signals (SYSBOOT[18..0]), that can be set on the EVM using resistors and switches to define some startup parameters on the AM437x processor. See the Configuration/Setup section later for more details.

Clocks
The EVM has several clocks to support the AM437x processor. The main clock for the processor is derived from a 24MHz crystal. AM437x generates the base clock and subsequent module clocks as needed within the AM437x processor. A 32kHz clock for the RTC on the AM437x is derived from a 32.768kHz crystal on the board. An external 12MHz crystal oscillator is used to generate the source clock for the audio codec. There are resistor population options that can allow this source clock to be generated from the AM437x directly if needed.

Reset Signals
SYS_RESETn is a reset signal running to several peripherals and AM437x which performs a reset on those peripherals and the processor. SYS_RESETn is asserted by the pushbutton and is used to force a reset of the AM437x and the other peripherals. AM437x can also pulldown on the RESET_INOUTn signal to cause the SYS_RESETn line to go active. The Power on Reset to the Processor is driven from the power good signal of the Power Manager.Also a Reset Push button is provided for the Power on Reset of the board.

DDR3 SDRAM
The AM437x GP EVM contains four 4 Gb (512M x 8) of DDR3L SDRAM memories from Micron. The Part number for the DDR3L SDRAM memory used is MT41K512M8RH. The package used is an 78 ball FBGA package. See the AM437x TRM for memory address locations for this memory.

NAND Flash
The GP EVM has a NAND type of flash. The part number of the memory used is MT29F4G08AB which is a 4G (512M x 8) flash memory. The GPMC signals are used to communicate with this memory.

Board Identity Memory
This board contains a serial EEPROM that contains board specific data that allows the processor to automatically detect which board is connected and the version of that board. Other hardware specific data can be stored on this memory device as well. The part number of the memory device is CAT24C256WI-G. See the Configuration/Setup section for details on the data in this memory.

SDMMC0
The SDMMC0 connector on the GP EVM is a Micro SD socket with part number SCHA5B0200. This is a standard SD/MMC Card type of connector. It is connected to the MMC0 port of the AM437x processor. Check the AM437x data sheet and TRM for supported card types/densities.

10/100/1000 Ethernet
The AM437x GP EVM has a 10/100/1000 Ethernet transceiver from Micrel(KSZ9031RN)that is connected to an RJ45 (J18) connector.

The reset on the transceiver is driven by the board system reset signal SYS_RESETn. A 25MHz crystal drives the clock input of the KSZ9031RN Ethernet PHY.

The PHY address on the MDIO bus is set to 0x00h.

USB
The AM437x GP EVM supports 2 USB ports. The USB ports are connected to a microUSB AB connector and a standard A type connector. The ESD device TPD4S012 and common choke filter ACM2012 (TDK) are used on the USB signals before they are connected to the AM437x pins. USB0 port is setup for dual role configuration and the USB1 port is setup for host mode only.

Connectivity
The AM437x GP EVM supports MCS COM8 form factor wireless boards from TI through the J20 COM connector which is a Samtec card edge type connector pn# MEC6-150-02-S-D-RA1. This connector thus supports COM8 types of boards, and more details about this connector can be found in the MCS COM8 board documents.

The COM connector requires 3.6V, 442mA on the power supply. Thus a TPS79501 LDO regulator is used to provide this voltage supply from the base 5.0V supply.

The signals on the COM board are all 1.8V voltage levels. Thus several of the I/O banks on the AM437x that connect to the COM8 connector are powered by 1.8V and voltage translators are placed for some signals to convert to/from 3.3V of the AM437x rail for a particular signal which is running at 3.3V.

UART
This EVM supports one RS232 port connector. MAX3243 RS232 transceiver is used in between UART0 signals from the processor and the standard male DB9 connector.

ADC
The Analog inputs to the AM437x are terminated on the Connector J22. This allows various analog signals to be measured from external sensors, devices, etc. The input range on these inputs is 0 to 1.8V. See the AM437x datasheet and TRM for more information on these inputs.

Dual Cameras
The two Camera Interfaces from the AM437x processor are terminated at J2 connector for a camera module and on the 12x2 header J3. The custom made Camera board from TI with part number #4P0041 shall be interfaced with the header J3. This camera module is on a separate camera board that attaches at a right angle so that the camera can face horizontally when the GP EVM is laying on a testbench. The OV2659 SOC (OmniVision) based 2MP camera module from SunnyOptics with part number #P212A is also attached directly to the connector J2. The OV2659 delivers a high-definition (HD) video and excellent low-light sensitivity for cost-sensitive applications.

Audio
The headphone output and line input signals from the two 3.5mm SJ3524 jacks are connected to the Audio codec with part number TLV320AIC3106. These are connected through the McASP1 and I2C1 interfaces of the AM437x.

= Power Supplies =

This section describes how the power supplies required for the design are generated.

Power Source
AM437x GP EVM uses an external AC to +5VDC (rated 2.5A min) power adapter. The slide switch SW2 is used to switch the main power to the board ON/OFF. The main power is off when the power switch is in the position away from the power supply jack. The main power is on when the power switch is in the position closest to the power supply jack.

Power Sequencing
The power sequencing requirements of the AM437X processor (see the AM437x datasheet) are handled automatically by the TPS65218 PMIC.

Power Management IC Power Supplies
The AM437x GP EVM uses the TPS65218 power management IC.

The I2C0 on AM437x is used to control the Smart Reflex port and control port on the TPS65218.

The following table provides the details on the power supplies used.

Table 1: AM437x Power supplies from TPS65218

Note: The TPS65218 power management IC that is used on the AM437x GP EVM rev. 1.2 has several issues which can affect operation. Refer to the errata at (add link) for the TPS65218 for more details.

Other Power Supplies used
Table 2: Other Power supplies

APM Sense Resistors
The AM437x GP EVM has the following subsystems with current sense resistors. These resistors allow the power to be measured on each power rail to check AM437x power requirements during real time software execution. The value of the resistors is selected to provide the best dynamic range when using a TI INA226 converter. In fact an INA226 converter is installed on the EVM for both the VDD_CORE and VDD_MPU power supply rails of the AM437x. The other power rails have sense resistors, but have their measurement connections attached to 2pin standard headers so that they can be read easily by a multimeter or connected to Power Measurement Daughtercard which has an INA226.

Note the value of the sense resistors for the VDD_CORE and VDD_MPU were selected to give better dynamic range for active power modes rather than sleep/low power modes. If power is to be measured for VDD_CORE or VDD_MPU for sleep/low power modes then this sense resistor value should be changed to give better shunt voltage values.

Table 3: AM437x GP EVM APM Sense Resistors

= Configuration/Setup =

Boot Configuration
The AM437x has SYSBOOT pins that can be configured using two 5 bit DIP switches on the EVM. These SYSBOOT switches will configure the AM437x to different boot settings. SW12 switch can be used to set the SYSBOOT[0..4] bits and SW11 switch can set the SYSBOOT[5,6,9,12,13)bits. Other SysBoot pin settings which are less likely to change from the default are done through resistors either pulled high or low. See the AM437x TRM and datasheet for the actual definitions of each of the SYSBOOT signals. Refer to the GP EVM schematic for more details.

I2C Address Assignments
In the AM437x GP EVM boards, each separate board has an I2C ID memory that contains the details of the identity of that board such as it's configuration, etc. (see sections below for more details on the memories' contents).

Table 4: AM437x I2C Bus Addresses

I2C ID Memory
The GP EVM has a dedicated I2C EEPROM which contains specific identity/configuration information for that board. In addition, there is available space in each memory for user specific configuration information.

The part number of the memory device is pn#CAT24C256WI-G.

Table 5: AM437x GP EVM EEPROM Data

JTAG
The AM437x GP EVM supports embedded XDS100V2 USB Emulation through the MicroUSB AB connector. It also has an optional 20 pin TI CJTAG connector to support the Emulation. This CJTAG connector is installed by default. Other JTAG adaptors are available on TI e-store and can be purchased from here

= User Interfaces =

Keypad
The keypad has 6 push button switches (SW4, SW5, SW6, SW7, SW8, SW9) with Omron Part Number # B3SL-1022P on the component side of the board. This keypad uses 2 power and 3 scan lines to enable 6 buttons to be monitored.

LEDs
There are eight status LEDs ( 3 Green LEDs,1 Yellow LED, 1 Red LED, 1 Blue LED & 1 Orange LED) on the top side of the EVM. There is also a Power On indication LED D2 of GREEN colour available in the EVM.

Audio Buzzer
An Audio buzzer is installed on the board to provide auditory cues to the user. This audio buzzer PUI Audio pn# AI-1027-TWT-3V-R is driven from a GPIO.

Capacitive Touch LCD
The LCD is a 7 inch WVGA (800x480) RGB LCD panel part number #OSD070T1718-19TS. It is a 24bit RGB TFT LCD with 21 white LEDs for backlight (controlled by the TPS61081DRC power regulator). The connector used is an FPC type, 50pin connector with part number #FH12S-50S-0.5SH. The LED backlight on the LCD is controlled by a PWM controlled LED driver (TPS61081). The LCD has a Capacitive Touch screen which is connected to the I2C0 port of the Processor. The Power required for the LCD is generated using the Linear regulator supply (TPS65105).

= Pin Use Description =

Functional Interface Mapping
Most signals of the AM437x are connected to a fixed device on the EVM where they cannot be changed.

- Assignment list of pin functions

GPIO Definitions
See the updated pinmux documents which show use case columns for GPIO's. Developer can select and enable pins based on the selective peripheral pins as output or input.

= Board Connectors =

The pinout details of all the connectors used in the GP EVM are provided below.

Battery Board Connector - J1
Table 6: Battery Board connector

HEADPHONE OUT - J16
Table 7: Audio Out Connector

LINE IN - J14
Table 8: Audio Line in Connector

SDMMC0 - J7
Table 9: SDMMC0 Connector

LCD Connector - J15
Table 10: LCD Connector

Touch Screen Connector - J17
Table 11: LCD Capacitive Touch Screen Pin Details

Ethernet - J18
Table 12: 10/100/1000 Ethernet Connector

USB - J11
Table 13: Micro AB connector - USB 0

USB - J13
Table 14: Type A - USB Port1

Camera Interface 0 - J2
Table 15: Camera Header 0

Camera Interface 1 - J3
Table 16: Camera Header 1

HDMI Connector - J19
Table 17: HDMI Header

RS232 Connector - J9
Table 18: RS232 connector

CAN INTERFACE 0 - J4
Table 19: CAN 0 connector

CAN INTERFACE 1 - J37
Table 20: CAN 1 connector

ADC Input Header - J22
Table 21: ADC Input Header

GPIO Header - J30
Table 22: GPIO Header

I2C - Header - J6
Table 23: I2C Header

= Appendix A: PCB Guideline Deviations =

PCB Guidelines deviation with respect to datasheet is provided below.

'''Table 24: PCB Guidelines Deviations

= EVM Important Notices =

= ANNEX =

This HUG is prepared by using the following documents as references.


 * 1) AM437x Sitara ARM Microprocessors TRM (SPRUHxx)