CY7C68300 CY7C68300 EZ-USB AT2™ USB 2.0 to ATA/ATAPI Bridge Document #: 38-08011 Rev. *B Page 1 of 26 CY7C68300 CONTENTS 1.0 INTRODUCTION .............................................................................................................................. 4 1.1 Features ...................................................................................................................................... 4 2.0 PIN ASSIGNMENTS ........................................................................................................................ 6 2.1 Pin Diagram ................................................................................................................................ 6 2.2 Pin Descriptions .......................................................................................................................... 8 2.3 Additional Pin Descriptions ......................................................................................................... 9 2.3.1 DPLUS, DMINUS .............................................................................................................................. 9 2.3.2 SCL, SDA .......................................................................................................................................... 9 2.3.3 XTALIN, XTALOUT ........................................................................................................................... 9 2.3.4 ATA_EN ..........................................................................................................................................10 2.3.5 ATA Interface Pins .......................................................................................................................... 10 2.3.6 VBUS_PWR_VALID ........................................................................................................................10 2.3.7 RESET# ..........................................................................................................................................10 3.0 APPLICATIONS ............................................................................................................................. 10 3.1 Additional Resources ................................................................................................................ 10 4.0 FUNCTIONAL OVERVIEW ............................................................................................................ 11 4.1 USB Signaling Speed ............................................................................................................... 11 4.2 ATA Interface ............................................................................................................................ 11 5.0 ENUMERATION ............................................................................................................................. 11 5.1 Board Manufacturing Test Mode ............................................................................................... 11 5.1.1 CfgCB .............................................................................................................................................. 11 5.1.2 MfgCB ............................................................................................................................................. 12 5.2 Normal Operation Mode ............................................................................................................ 13 5.3 EEPROM Organization ............................................................................................................. 13 6.0 ABSOLUTE MAXIMUM RATINGS ................................................................................................ 22 7.0 OPERATING CONDITIONS ............................................................................................................ 22 8.0 DC CHARACTERISTICS ............................................................................................................... 22 9.0 AC ELECTRICAL CHARACTERISTICS ....................................................................................... 22 9.1 USB Transceiver ....................................................................................................................... 22 9.2 ATA Timing ............................................................................................................................... 22 10.0 ORDERING INFORMATION ........................................................................................................ 23 11.0 PACKAGE DIAGRAMS ............................................................................................................. 23 12.0 PCB LAYOUT RECOMMENDATIONS ........................................................................................ 24 13.0 QUAD FLAT PACKAGE NO LEADS (QFN) PACKAGE DESIGN NOTES ................................ 24 14.0 OTHER DESIGN CONSIDERATIONS ......................................................................................... 25 14.1 Proper Power-up Sequence .................................................................................................... 25 14.2 IDE Removable Media Devices .............................................................................................. 25 14.3 Devices With Small Buffers ..................................................................................................... 25 14.4 USB Idle Mode ........................................................................................................................ 25 15.0 DISCLAIMERS, TRADEMARKS, AND COPYRIGHTS ............................................................... 25 Document #: 38-08011 Rev. *B Page 2 of 26 CY7C68300 LIST OF FIGURES Figure 1-1. Block Diagram ....................................................................................................................... 5 Figure 2-1. 56-pin SSOP ......................................................................................................................... 6 Figure 2-2. 56-pin QFN ............................................................................................................................ 7 Figure 2-3. XTALIN, XTALOUT Diagram............................................................................................... 10 Figure 2-4. Typical Reset Circuit ........................................................................................................... 10 Figure 11-1. 56-lead Shrunk Small Outline Package 056...................................................................... 23 Figure 11-2. 56-lead Quad Flatpack No Lead (8 x 8 mm) LF56 ............................................................ 23 Figure 13-1. Cross-Section of the Area Underneath the QFN Package ................................................ 24 Figure 13-2. Plot of the Solder Mask (White Area) ................................................................................ 25 Figure 13-3. X-ray Image of the Assembly ............................................................................................ 25 LIST OF TABLES Table 5-1. Command Block Wrapper ................................................................................................... 11 Table 5-2. Example CfgCB ................................................................................................................... 11 Table 5-3. Example MfgCB ................................................................................................................... 12 Table 5-4. Mfg_load Data Format ......................................................................................................... 12 Table 5-5. Mfg_read Data Format ........................................................................................................ 13 Table 5-6. EEPROM Organization ........................................................................................................ 14 Document #: 38-08011 Rev. *B Page 3 of 26 CY7C68300 1.0 Introduction The EZ-USB AT2 implements a fixed function bridge between one USB port and one ATA- or ATAPI-based mass storage device port. This bridge adheres to the Mass Storage Class Bulk-Only Transport Specification and is intended for self-powered devices. The USB port of the EZ-USB AT2 is connected to a host computer directly or via the downstream port of a USB hub. Host software issues commands and data to the EZ-USB AT2 and receives status and data from the EZ-USB AT2 using standard USB protocol. The ATA/ATAPI port of the EZ-USB AT2 is connected to a mass storage device. A 4-Kbyte buffer maximizes ATA/ATAPI data transfer rates by minimizing losses due to device seek times. The ATA interface supports ATA PIO modes 0, 3, and 4, and Ultra DMA modes 2 and 4. The device initialization process is configurable, enabling the EZ-USB AT2 to initialize ATA/ATAPI devices without software intervention. 1.1 Features • Complies with USB-IF specifications for USB 2.0, the USB Mass Storage Class, and the USB Mass Storage Class Bulk-Only Transport Specification • Operates at high (480-Mbps) or full (12-Mbps) speed • Complies with T13’s ATA/ATAPI-6 Draft Specification • Supports 48-bit addressing for large hard drives • Supports PIO modes 0, 3, 4, and UDMA modes 2, 4 • Uses one external serial EEPROM containing the USB device serial number, vendor and product identification data, and device configuration data • ATA interface IRQ signal support • Support for ATA/ATAPI devices configured either as master or slave • “ATA-Enable” input signal, which three-states all signals on the ATA interface in order to allow sharing of the bus with another controller (e.g., an IEEE-1394 to ATA bridge chip) • Support for board-level manufacturing test via USB interface • 3.3V operation for self-powered devices • 56-pin SSOP and 56-pin QFN packages. Document #: 38-08011 Rev. *B Page 4 of 26 CY7C68300 I2C-Compatible Bus Controller SDA 24 MHz XTAL RESET SCL PLL ATA_EN (ATA Interface 3-state) AT2 Internal Logic ATA Interface Control Signals Control ATA Interface Logic VBUS D+ D- USB 2.0 XCVR CY Smart USB FS/HS Engine 4kByte FIFO 16 Bit ATA Data Data Figure 1-1. Block Diagram Document #: 38-08011 Rev. *B Page 5 of 26 CY7C68300 2.0 2.1 Pin Assignments Pin Diagram 1 DD13 DD12 56 2 DD14 DD11 55 3 DD15 DD10 54 4 GND DD9 53 5 NC DD8 52 6 Vcc ATA_EN 51 7 GND Vcc 50 8 IORDY RESET# 49 9 DMARQ GND 48 10 AVcc ARESET# 47 11 XTALOUT VBUS_PWR_VALID 46 12 XTALIN CS1# 45 13 AGND CS0# 44 14 Vcc DA2 43 15 DPLUS DA1 42 16 DMINUS DA0 41 17 GND INTRQ 40 18 Vcc Vcc 39 19 GND DMACK# 38 20 PU10K DIOR# 37 21 RESERVED DIOW# 36 22 SCL GND 35 23 SDA Vcc 34 24 Vcc GND 33 25 DD0 DD7 32 26 DD1 DD6 31 27 DD2 DD5 30 28 DD3 DD4 29 EZ-USB AT2 CY7C68300 Figure 2-1. 56-pin SSOP Document #: 38-08011 Rev. *B Page 6 of 26 CY7C68300 GND VCC NC GND DD15 DD14 DD13 DD12 DD11 DD10 DD9 DD8 ATA_EN VCC 56 55 54 53 52 51 50 49 48 47 46 45 44 43 IORDY 1 42 RESET# DMARQ 2 41 GND AVCC 3 40 ARESET# XTALOUT 4 39 XTALIN 5 38 CS1# AGND 6 37 CS0# VCC 7 36 DA2 DPLUS 8 35 DA1 DMINUS 9 34 DA0 GND 10 33 INTRQ VCC 11 32 VCC GND 12 31 DMACK# PU10K 13 30 DIOR# RESERVED 14 29 DIOW# EZ-USB AT2 CY7C68300 56-pin QFN VBUS_PWR_VALID 23 24 25 26 27 28 DD4 DD5 DD6 DD7 GND VCC GND DD1 22 19 DD0 DD3 18 VCC 21 17 SDA DD2 16 SCL 20 15 Figure 2-2. 56-pin QFN Document #: 38-08011 Rev. *B Page 7 of 26 CY7C68300 2.2 Pin Descriptions SSOP QFN Pin Pin Pin Name Pin Type Default State at Start-up Pin Description 1 50 DD13 I/O[1] Hi-Z ATA Data bit 13. 2 51 DD14 I/O[1] Hi-Z ATA Data bit 14. 3 52 DD15 I/O[1] Hi-Z ATA Data bit 15. 4 53 GND GND 5 54 NC 6 55 VCC PWR VCC. Connect to 3.3V power source. 7 56 GND GND Ground. [1] I ATA Control. I ATA Control. Ground. Hi-Z 8 1 IORDY I 9 2 DMARQ I[1] 10 3 AVCC PWR Reserved. This pin should remain a no-connect. Analog VCC. Connect the VCC through the shortest path possible. 11 4 XTALOUT Xtal Xtal 24-MHz Crystal Output (see subsection 2.3.3). 12 5 XTALIN Xtal Xtal 24-MHz Crystal Input (see subsection 2.3.3). 13 6 AGND GND 14 7 VCC PWR 15 8 DPLUS I/O 16 9 DMINUS I/O 17 10 GND GND Ground. 18 11 VCC PWR VCC. Connect to 3.3V power source. 19 12 GND GND 20 13 PU10K 21 14 RESERVED 22 15 SCL O 23 16 SDA I/O 24 17 VCC PWR 25 18 DD0 I/O Hi-Z ATA Data bit 0. 26 19 DD1 I/O Hi-Z ATA Data bit 1. 27 20 DD2 I/O Hi-Z ATA Data bit 2. 28 21 DD3 I/O Hi-Z ATA Data bit 3. 29 22 DD4 I/O Hi-Z ATA Data bit 4. 30 23 DD5 I/O Hi-Z ATA Data bit 5. 31 24 DD6 I/O Hi-Z ATA Data bit 6. 32 25 DD7 I/O Hi-Z ATA Data bit 7. 33 26 GND GND Ground. 34 27 VCC PWR VCC. Connect to 3.3V power source. 35 28 GND GND Ground. Analog Ground. Connect to ground with as short a path as possible. VCC. Connect to 3.3V power source. Pulled high at Reset. When USB D+ Signal (see subsection 2.3.1). the firmware starts, the pullup is controlled by pin 46(SSOP) / 39(QFN). When VBUS_PWR _VALID is high, the line is pulled up. VBUS_PWR _VALID is polled at start-up and then every 20 ms. Hi-Z USB D- Signal (see subsection 2.3.1). Ground. Hi-Z Tied to 10k ± 5% pull-up resistor. Reserved. Tie to GND. SCL/SDA will be active for several ms at start-up. Then driven high. Clock signal for I2C-compatible interface (see 2.3.2). Data signal for I2C-compatible interface (see 2.3.2). VCC. Connect to 3.3V power source. Note: 1. ATA interface pins are not active when ATA_EN is not asserted. Document #: 38-08011 Rev. *B Page 8 of 26 CY7C68300 2.2 Pin Descriptions (continued) SSOP QFN Pin Pin Pin Name Pin Type [2] [1] Driven high (CMOS) ATA Control. O/Z[1] Driven high (CMOS) ATA Control. [1] Driven high (CMOS) ATA Control. 36 29 37 30 DIOW# DIOR# O/Z 38 31 DMACK# 39 32 VCC PWR I[1] 40 33 INTRQ 41 34 DA0 O/Z Default State at Start-up VCC. Connect to 3.3V power source. Input O/Z[1] Driven high after 2 ms delay [1] Pin Description IDE ATA Interrupt request. ATA Address. 42 35 DA1 O/Z Driven high after 2 ms delay ATA Address. 43 36 DA2 O/Z[1] Driven high after 2 ms delay ATA Address. [1] 44 37 CS0# O/Z Driven high after 2 ms delay ATA Chip Select. 45 38 CS1# O/Z[1] Driven high after 2 ms delay ATA Chip Select. 46 39 VBUS_PW R_VALID I 47 40 ARESET# O/Z[1] ATA Reset. 48 41 GND GND Ground. 49 42 RESET# I 50 43 VCC PWR 51 44 ATA_EN I Input – If AT2 is not in mfg mode, polled every 20 ms after start-up. If LOW, SSOP: pins 36–38, 41–45 and 47 are three-stated. QFN: pins 29–31, 34–38 and 40 are three-stated. 52 45 DD8 I/O[1] Hi-Z ATA Data bit 8. Input VBUS detection. Indicates to the EZ-USB AT2 that VBUS power is present. Active LOW Reset. Resets the entire chip. This pin is normally tied to VCC through a 100K resistor, and to GND through a 0.1-µF capacitor, supplying a 10-ms reset. VCC. Connect to 3.3V power source. Active HIGH. ATA interface enable. Allows ATA bus sharing with other host devices. Setting ATA_EN=1 enables the ATA interface for normal operation. Disabling ATA_EN threestates (High-Z) the ATA interface and halts the ATA interface state machine logic. 53 46 DD9 I/O[1] Hi-Z ATA Data bit 9. 54 47 DD10 I/O[1] Hi-Z ATA Data bit 10. Hi-Z ATA Data bit 11. Hi-Z ATA Data bit 12. 55 48 DD11 I/O[1] 56 49 DD12 I/O[1] 2.3 Additional Pin Descriptions 2.3.1 DPLUS, DMINUS DPLUS and DMINUS are the USB signaling pins, and they should be tied to the D+ and D– pins of the USB connector. Because they operate at high frequencies, the USB signals require special consideration when designing the layout of the PCB. 2.3.2 SCL, SDA The clock and data pins for the I2C-compatible port should be connected to your configuration EEPROM and to VCC through 2.2k resistors. 2.3.3 XTALIN, XTALOUT The EZ-USB AT2 requires a 24-MHz signal to derive internal timing. Typically a 24-MHz parallel-resonant fundamental mode crystal is used, but a 24-MHz square wave from another source can also be used. If a crystal is used, connect the pins to XTALIN and XTALOUT, and also through 20-pF capacitors to GND. If an alternate clock source is used, apply it to XTALIN and leave XTALOUT open. Note: 2. A # sign after the signal name indicates it is an active LOW signal. Document #: 38-08011 Rev. *B Page 9 of 26 CY7C68300 2 4 M H z crys ta l 20pF 20pF Figure 2-3. XTALIN, XTALOUT Diagram 2.3.4 ATA_EN ATA_EN allows bus sharing with other host devices. Setting ATA_EN = 1 enables the ATA interface for normal operation. Setting ATA_EN = 0 disables (High-Z) the ATA interface pins and removes the EZ-USB AT2 from the USB. The ATA_EN pin is sampled at a rate of 60 times per second by the EZ-USB AT2 internal logic. This pin should be set to a HIGH at start-up. Upon a HIGH to LOW transition all EZ-USB AT2 ATA signals are tri-stated, USB is disconnected, and the EZ-USB AT2 enters an idle state until an active Reset is received, or the ATA_EN pin transitions back to a HIGH state. Upon sensing the LOW to HIGH transition the EZ-USB AT2 will return to the post Reset operational state, and will reconnect to USB. Note that disabling the ATA bus with the ATA_EN pin during the middle of a data transfer will result in data loss and can cause the operating system on the Host computer to crash. 2.3.5 ATA Interface Pins Design practices as outlined in the ATA/ATAPI-6 Specification for signal integrity should be followed with systems that utilize a ribbon cable interconnect between the EZ-USB AT2’s ATA interface and the attached ATA/ATAPI device, especially if Ultra DMA Mode is utilized. 2.3.6 VBUS_PWR_VALID VBUS_PWR_VALID indicates to the EZ-USB AT2 that power is present on VBUS. 2.3.7 RESET# Asserting RESET# for 10 ms will reset the entire chip. This pin is normally tied to VCC through a 100k resistor, and to GND through a 0.1-µF capacitor. R 8 1 0 0 K N R E S E T C 1 0 .1 u F d Figure 2-4. Typical Reset Circuit 3.0 Applications The EZ-USB AT2 is a high-speed USB 2.0 peripheral device that connects ATA or ATAPI storage devices to a USB host using the USB Mass Storage Class protocol. 3.1 • • • • Additional Resources CY4615 EZ-USB AT2 Reference Design Kit USB Specification version 2.0 ATA Specification T13/1410D Rev 3B USB Mass Storage Class Bulk Only Transport Specification, http://www.usb.org/developers/data/devclass/ usbmassbulk_10.pdf. Document #: 38-08011 Rev. *B Page 10 of 26 CY7C68300 4.0 4.1 Functional Overview USB Signaling Speed EZ-USB AT2 operates at two of the three rates defined in the USB Specification Revision 2.0 dated April 27, 2000: • Full speed, with a signaling bit rate of 12 Mbits/sec • High speed, with a signaling bit rate of 480 Mbits/sec. EZ-USB AT2 does not support the low-speed signaling rate of 1.5 Mbits/sec. 4.2 ATA Interface The ATA/ATAPI port on the EZ-USB AT2 is compliant with the Information Technology AT Attachment with Packet Interface 6 (ATA/ATAPI-6) Specification, T13/1410D Rev 3B. The EZ-USB AT2 supports both ATAPI packet commands over USB. Additionally, the EZ-USB AT2 translates ATAPI SFF-8070i commands to ATA commands for seamless integration of ATA devices with generic Mass Storage Class BOT drivers. 5.0 Enumeration During the power-up sequence, internal logic checks the I2C-compatible port for an EEPROM whose first two bytes are both 0x4D. If a valid signature is found, the EZ-USB AT2 uses the values stored in the EEPROM to configure the USB descriptors for normal operation. If an invalid EEPROM signature is read, or if no EEPROM is detected, the EZ-USB AT2 defaults into Board Manufacturing Test Mode. The two modes of operation are described in subsections 5.1 and 5.2, below. 5.1 Board Manufacturing Test Mode In Board Manufacturing Test Mode, the chip behaves as a USB 2.0 device but the ATA/ATAPI interface is not active. The EZ-USB AT2 allows for reading and writing an EEPROM and for board level testing through vendor specific ATAPI commands utilizing the CBW Command Block as described in the USB Mass Storage Class Bulk-Only Transport Specification. There is a vendor-specific ATAPI command for the EEPROM access (CfgCB) and one for the board level testing (MfgCB). 5.1.1 CfgCB The cfg_load and cfg_read vendor-specific commands are passed down through the bulk pipe in the CBWCB portion of the CBW. The format of this CfgCB is shown below. Byte 0 will be a vendor-specific command designator whose value is configurable and set in the configuration data (EEPROM address 0x04). Byte 1 must be set to 0x26 to identify CfgCB. Byte 2 is reserved and must be set to zero. Byte 3 is used to determine the memory source to write/read. For the EZ-USB AT2, this byte must be set to 0x02, meaning the EEPROM. Bytes 4 and 5 will be used to determine the start address. For the EZ-USB AT2, this must always be 0x0000. Bytes 6 through 15 are reserved and should be set to zero. The data transferred to the EEPROM must be in the format specified in Table 5-6 of this data sheet. Maximum data transfer size is 255 bytes. The data transfer length is determined by the CBW Data Transfer Length specified in bytes 8 through 11 (dCBWDataTransferLength) of the CBW. The type/direction of the command will be determined by the direction bit specified in byte 12, bit 7 (bmCBWFlags) of the CBW. Table 5-1. Command Block Wrapper 7 6 5 4 0–3 3 2 1 0 DCBWSignature 4–7 dCBWTag 8–11 (08h-0Bh) dCBWDataTransferLength 12 (0Ch) bwCBWFLAGS Dir Obsolete 13 (0Dh) Reserved (0) Reserved (0) 14 (0Eh) bCBWLUN Reserved (0) bCBWCBLength 15-30 (0Fh1Eh) CBWCB (CfgCB or MfgCB) Table 5-2. Example CfgCB CfgCB Byte Descriptions 0 bVSCBSignature (set in configuration bytes) Document #: 38-08011 Rev. *B Bits 7 6 5 4 3 2 1 0 0 0 1 0 0 1 0 0 Page 11 of 26 CY7C68300 Table 5-2. Example CfgCB (continued) CfgCB Byte Descriptions Bits 7 6 5 4 3 2 1 0 1 bVSCBSubCommand (must be 0x26) 0 0 1 0 0 1 1 0 2 Reserved (must be set to zero) 0 0 0 0 0 0 0 0 3 Data Source (must be set to 0x02) 0 0 0 0 0 0 1 0 4 Start Address (LSB) (must be set to zero) 0 0 0 0 0 0 0 0 5 Start Address (MSB) (must be set to zero) 0 0 0 0 0 0 0 0 6–15 Reserved (must be set to zero) 0 0 0 0 0 0 0 0 5.1.2 MfgCB The mfg_load and mfg_read vendor-specific commands will be passed down through the bulk pipe in the CBWCB portion of the CBW. The format of this MFGCB is shown below. Byte 0 is a vendor-specific command designator whose value is configurable and set in the configuration data. Byte 1 must be 0x27 to identify MfgCB. Byte 2–15 are reserved and must be set to zero. The data transfer length will be determined by the CBW Data Transfer Length specified in bytes 8 through 11 (dCBWDataTransferLength) of the CBW. The type/direction of the command is determined by the direction bit specified in byte 12, bit 7 (bmCBWFlags) of the CBW. Table 5-3. Example MfgCB MfgCB Byte Description Bits 0 bVSCBSignature (set in configuration bytes) 0 0 1 0 0 1 0 0 1 bVSCBSubCommand (hardcoded 0x27) 0 0 1 0 0 1 1 1 2–15 Reserved (must be zero) 0 0 0 0 0 0 0 0 5.1.2.1 Mfg_load During a mfg_load, the EZ-USB AT2 goes into Manufacturing Test Mode. Manufacturing Test Mode is provided as a means to implement board or system level interconnect tests. During Manufacturing Test Mode operation, all outputs not directly associated with USB operation are controllable. Normal control of the output pins are disabled. Control of the select EZ-USB AT2 IO pins and their three-state controls are mapped to the ATAPI data packet associated with this request. (See the following table for explanation of the required mfg_load data format.) This requires a write of seven bytes. To exit Manufacturing Test Mode, a hard reset (#RESET) is required. Table 5-4. Mfg_load Data Format Byte Bit(s) 0 0 Test/Three-state Control Function Reserved 0 3:1 DA[2:0] 0 5:4 CS#[1:0] 0 6 Reserved 0 7 ARESET# 1 0 NDIOW 1 1 NDIOR 1 2 NDMACK 1 3:6 Reserved 1 7 2 7:0 DD[15:0] Three-state (0 = three-state DD pins, 1 = enable DD pins). DD[7:0] 3 7:0 DD[15:8] 4 7:0 Reserved 5 7:0 Reserved 6 7:0 Reserved Document #: 38-08011 Rev. *B Page 12 of 26 CY7C68300 5.1.2.2 Mfg_read This USB request returns a “snapshot in time” of select EZ-USB AT2 input pins. The input pin states are bit-wise mapped to the ATAPI data associated with this request. EZ-USB AT2 input pins not directly associated with USB operation can be sampled at any time during Manufacturing Test Mode operation. See the following table for an explanation of the mfg_read data format. The data length shall always be eight bytes. Table 5-5. Mfg_read Data Format Byte Bit(s) 0 0 0 5:1 0 6 VBUS_PWR_VALID 0 7 ARESET# (output value only) 1 2:0 1 3 IORDY 1 4 DMARQ 1 5 ATA_EN 1 6 Reserved. This data should be ignored. 5.2 Test/Three-state Control Function INTRQ Reserved. This data should be ignored. Reserved. This data should be ignored. 1 7 2 7:0 DD[7:0] DD[15:0] Tri-state 3 7:0 DD[15:8] 4 7:0 Reserved. This data should be ignored. 5 7:0 Reserved. This data should be ignored. 6 7:0 Reserved. This data should be ignored. 7 7:0 Reserved. This data should be ignored. Normal Operation Mode In Normal Operation Mode, the chip behaves as a USB 2.0 to ATA/ATAPI bridge. This includes all typical USB device states (powered, configured, etc.). The USB descriptors are returned according to the values stored in the external EEPROM. An external EEPROM is required for Mass Storage Class Bulk-Only Transport compliance, since a unique serial number is required for each device. Also, Cypress requires customers to use their own Vendor and Product IDs for final products. 5.3 EEPROM Organization The contents of the 256-byte (2048-bit) two-wire serial EEPROM are arranged as follows. The column labeled “Required Contents” contains the values that must be used for proper operation of the EZ-USB AT2. The column labeled “Suggested Contents” contains suggested values for the bytes that are defined by the manufacturer. Some values, such as the Vendor ID and device and device serial number, must be customized to meet USB compliance. See subsection 5.1 for details on how to use vendor-specific ATAPI commands to read and program the EEPROM. The serial EEPROM must be hard-wired to address 0x04. This means that A0 and A1 of the serial EEPROM must be tied to ground and that A2 must be tied to 3.3V. Document #: 38-08011 Rev. *B Page 13 of 26 CY7C68300 Table 5-6. EEPROM Organization EEPROM Address Field Name Field Description Required Suggested Contents Contents Configuration 0x00 I2C-compatible memory device signature (LSB) LSB I2C-compatible memory device signature byte. 0x4D 0x01 I2C-compatible memory device signature (MSB) MSB I2C-compatible memory device signature byte. 0x4D 0x02 APM Value ATA Device Automatic Power Management Value. If an attached ATA device supports APM and this field contains other than 0x00, the EZ-USB AT2 will issue a SET_FEATURES command to Enable APM with this value during the drive initialization process. Setting APM Value to 0x00 disables this functionality. This value is ignored with ATAPI devices. 0x00 0x03 ATA Initialization Timeout Time in 128-ms granularity before the EZ-USB AT2 stops polling the ALT STAT register for reset complete and restarts the reset process (0x80 = 16.4 seconds). 0x80 0x04 ATA Command Designator Value in the first byte of the CBW CB field that designates that the CB is t o be decoded as vendor specific ATA commands instead of the ATAPI command block. See section 4.0 for more detail on how this byte is used. 0x24 0x05 Reserved Bits(7:4) Set to 0 0x07 BUSY Bit Delay Bit (3) Enables a delay of up to 120 ms at each read of the DRQ bit where the device data length does not match the host data length. This allows the EZ-USB AT2 to work with most devices that incorrectly clear the BUSY bit before a valid status is present. Short Packet Before Stall Bit (2) Determines if a short packet is sent prior to the STALL of an IN endpoint. The USB Mass Storage Class Bulk-Only Specification allows a device to send a short or zero-length IN packet prior to returning a STALL handshake for certain cases. Certain host controller drivers may require a short packet prior to STALL. 1 = Force a short packet before STALL. 0 = Don’t force a short packet before STALL. SRST Enable Bit (1) Determines if the EZ-USB AT2 is to do a SRST reset during drive initialization.[3] 1 = Perform SRST during initialization. 0 = Don’t perform SRST during initialization. Skip Pin Reset Bit (0) Skip ATA_NRESET assertion.[4] 0 = Allow ARESET# assertion for all resets. 1 = Disable ARESET# assertion except for power-on reset cycles. Notes: 3. At least one reset must be enabled. Do not set SRST to 0 and Skip Pin Reset to 1at the same time. 4. SRST Enable must be set in conjunction with Skip Pin Reset. Setting this bit causes the EZ-USB AT2 to bypass ARESET# during initialization. All reset events except a power-on reset utilize SRST as the drive mechanism. Document #: 38-08011 Rev. *B Page 14 of 26 CY7C68300 Table 5-6. EEPROM Organization (continued) EEPROM Address 0x06 Field Name Field Description Required Suggested Contents Contents ATA UDMA Enable Bit (7) Enable Ultra DMA data transfer support for ATAPI devices. If enabled, and if the ATAPI device reports UDMA support for the indicated modes, the EZ-USB AT2 will utilize UDMA data transfers at the highest negotiated rate possible. 0 = Disable ATA device UDMA support. 1 = Enable ATA device UDMA support. ATAPI UDMA Enable Bit (6) Enable Ultra DMA data transfer support for ATAPI devices. If enabled, and if the ATAPI device reports UDMA support for the indicated modes, the EZ-USB AT2 will utilize UDMA data transfers at the highest negotiated rate possible. 0 = Disable ATAPI device UDMA support. 1 = Enable ATAPI device UDMA support. UDMA Modes Bit (5:0) These bits select which UDMA modes, if supported, are enabled. Setting to 1 enables. Multiple bits may be set. The EZ-USB AT2 will operate in the highest enabled UDMA mode supported by the device. The EZ-USB AT2 supports UDMA modes 2 and 4 only. Bit Descriptions 5 Reserved. Must be set to 0. 4 Enable UDMA mode 4. 3 Reserved. Must be set to 0. 2 Enable UDMA mode 2. 1 Reserved. Must be set to 0. 0 Reserved. Must be set to 0. 0x07 Reserved PIO Modes Bits(7:2) Bits(1:0) These bits select which PIO modes, if supported, are enabled. Setting to 1 enables. Multiple bits may be set. The EZ-USB AT2 will operate in the highest enabled PIO mode supported by the device. The EZ-USB AT2 supports PIO modes 0, 3, and 4 only. PIO mode 0 is always enabled by internal logic. Bit Descriptions 1 Enable PIO mode 4. 0 Enable PIO mode 3. 0x08 Reserved Must be set to 0x00. 0x00 0x09 Reserved Must be set to 0x00. 0x00 0x0A Reserved Must be set to 0x00. 0x00 0x0B Reserved Must be set to 0x00. 0x00 0x0C Reserved Must be set to 0x00. 0x00 0x0D Reserved Must be set to 0x00. 0x00 0x0E Reserved Must be set to 0x00. 0x00 0x0F Reserved Must be set to 0x00. 0x00 0xD4 0x03 Device Descriptor 0x10 bLength Length of device descriptor in bytes. 0x12 0x11 bDescriptor Type Descriptor type. 0x01 0x12 bcdUSB (LSB) USB Specification release number in BCD. 0x13 bcdUSB (MSB) 0x14 bDeviceClass Device class. 0x00 0x15 bDeviceSubClass Device subclass. 0x00 Document #: 38-08011 Rev. *B 0x00 0x02 Page 15 of 26 CY7C68300 Table 5-6. EEPROM Organization (continued) EEPROM Address 0x16 Field Name bDeviceProtocol Field Description Required Suggested Contents Contents Device protocol. 0x00 0x40 0x17 bMaxPacketSize0 USB packet size supported for default pipe. 0x18 idVendor (LSB) 0xB4 0x19 idVendor (MSB) Vendor ID. Cypress’s Vendor ID may only be used for evaluation purposes, and not in released products. 0x1A idProduct (LSB) Product ID. 0x30 0x04 0x1B idProduct (MSB) 0x1C bcdDevice (LSB) Device release number in BCD LSB (product release number). 0x68 0x01 0x1D bcdDevice (MSB) Device release number in BCD MSB (silicon release number). 0x00 0x1E iManufacturer Index to manufacturer string. This entry must equal half of the address value where the string starts or 0x00 if the string does not exist. 0x38 0x1F iProduct Index to product string. This entry must equal half of the address value where the string starts or 0x00 if the string does not exist. 0x4E 0x20 iSerialNumber Index to serial number string. This entry must equal half of the address value where the string starts or 0x00 if the string does not exist. The USB Mass Storage Class Bulk-Only Transport Specification requires a unique serial number (in upper case, hexidecimal characters) for each device. 0x64 0x21 bNumConfigurations Number of configurations supported. 0x01 Device Qualifier 0x22 bLength Length of device descriptor in bytes. 0x0A 0x23 bDescriptor Type Descriptor type. 0x06 0x24 bcdUSB (LSB) USB Specification release number in BCD. 0x00 0x25 bcdUSB (MSB) USB Specification release number in BCD. 0x02 0x26 bDeviceClass Device class. 0x00 0x27 bDeviceSubClass Device subclass. 0x00 0x28 bDeviceProtocol Device protocol. 0x00 0x29 bMaxPacketSize0 USB packet size supported for default pipe. 0x40 0x2A bNumConfigurations Number of configurations supported. 0x01 0x2B bReserved Reserved for future use. Must be set to zero. 0x00 bLength Length of configuration descriptor in bytes. 0x09 0x2D bDescriptorType Descriptor type. 0x02 0x2E bTotalLength (LSB) 0x20 0x2F bTotalLength (MSB) Number of bytes returned in this configuration. This includes the configuration descriptor plus all the interface and endpoint descriptors. High-speed Configuration Descriptor 0x2C 0x00 0x30 bNumInterfaces Number of interfaces supported. 0x01 0x31 bConfiguration Value The value to use as an argument to Set Configuration to select the configuration. This value must be set to 0x01. 0x01 0x32 iConfiguration Index to the configuration string. This entry must equal half of the address value where the string starts or 0x00 if the string does not exist. Document #: 38-08011 Rev. *B 0x00 Page 16 of 26 CY7C68300 Table 5-6. EEPROM Organization (continued) EEPROM Address Field Name Field Description 0x33 bmAttributes Device attributes for this configuration. Bit Descriptions 7 Reserved. Must be set to 1. 6 Self-powered. Must be set to 1. 5 Remote wake-up. Must be set to 0. 4-0 Reserved. Must be set to 0. 0x34 bMaxPower Maximum power consumption for this configuration. Units used are mA*2(i.e., 0x31 = 98 mA, 0xF9 = 498 mA). 0x00 reported for self-powered devices. Required Suggested Contents Contents 0xC0 0x00 High-speed Interface and Endpoint Descriptors Interface Descriptor 0x35 bLength Length of interface descriptor in bytes. 0x09 0x36 bDescriptorType Descriptor type. 0x04 0x37 bInterfaceNumber Interface number. 0x00 0x38 bAlternateSetting Alternate setting. 0x00 0x39 bNumEndpoints Number of endpoints. 0x02 0x3A bInterfaceClass Interface class. 0x08 0x3B bInterfaceSubClass Interface subclass. 0x3C bInterfaceProtocol Interface protocol. 0x3D iInterface Index to first interface string. This entry must equal half of the address value where the string starts or 0x00 if the string does not exist. 0x06 0x50 0x00 USB Bulk Out Endpoint 0x3E bLength Length of this descriptor in bytes. 0x07 0x3F bDescriptorType Endpoint descriptor type. 0x05 0x40 bEndpointAddress This is an Out endpoint, endpoint number 2. 0x02 0x41 bmAttributes This is a bulk endpoint. 0x02 0x42 wMaxPacketSize (LSB) Max data transfer size. 0x43 wMaxPacketSize (MSB) 0x44 bInterval 0x00 0x02 HS interval for polling (max NAK rate). 0x00 USB Bulk In Endpoint 0x45 bLength Length of this descriptor in bytes. 0x07 0x46 bDescriptorType Endpoint descriptor type. 0x05 0x47 bEndpointAddress This is an In endpoint, endpoint number 8. 0x88 0x48 bmAttributes This is a bulk endpoint. 0x02 0x49 wMaxPacketSize (LSB) Max data transfer size. 0x4A wMaxPacketSize (MSB) 0x4B bInterval 0x00 0x02 HS interval for polling (max NAK rate). 0x00 Full-speed Configuration Descriptor 0x4C bLength Length of configuration descriptor in bytes. 0x09 0x4D bDescriptorType Descriptor type. 0x02 0x4E bTotalLength (LSB) bTotalLength (MSB) Number of bytes returned in this configuration. This includes the configuration descriptor plus all the interface and endpoint descriptors. 0x20 0x4F 0x50 bNumInterfaces Number of interfaces supported. 0x01 0x51 bConfiguration Value The value to use as an argument to Set Configuration to select the configuration. 0x01 Document #: 38-08011 Rev. *B 0x00 Page 17 of 26 CY7C68300 Table 5-6. EEPROM Organization (continued) EEPROM Address Field Name Field Description 0x52 iConfiguration Index to configuration string. This entry must equal half of the address value where the string starts or 0x00 if the string does not exist. 0x53 bmAttributes Device attributes for this configuration. Bit Descriptions 7 Reserved. Must be set to 1. 6 Self-powered. Must be set to 1. 5 Remote wake-up. Must be set to 0. 4–0 Reserved. Must be set to 0. 0x54 bMaxPower Maximum power consumption for the second configuration. Units used are mA*2 (i.e., 0x31 = 98 mA, 0xF9 = 498 mA). Required Suggested Contents Contents 0x00 0xC0 0x00 Full-speed Interface and Endpoint Descriptors Interface Descriptor 0x55 bLength Length of interface descriptor in bytes. 0x09 0x56 bDescriptorType Descriptor type. 0x04 0x57 bInterfaceNumber Interface number. 0x00 0x58 bAlternateSettings Alternate settings. 0x00 0x59 bNumEndpoints Number of endpoints. 0x02 0x5A bInterfaceClass Interface class. 0x08 0x5B bInterfaceSubClass Interface subclass. 0x5C bInterfaceProtocol Interface protocol. 0x50 0x06 0x5D iInterface Index to first interface string. This entry must equal half of the address value where the string starts or 0x00 if the string does not exist. 0x00 USB Bulk Out Endpoint 0x5E bLength Length of this descriptor in bytes. 0x07 0x5F bDescriptorType Endpoint descriptor type. 0x05 0x60 bEndpointAddress This is an Out endpoint, endpoint number 2. 0x02 0x61 bmAttributes This is a bulk endpoint. 0x02 0x62 wMaxPacketSize (LSB) Max data transfer size. 0x63 wMaxPacketSize (MSB) 0x64 bInterval 0x40 0x00 Does not apply to FS bulk endpoints. Must be set to 0. 0x00 USB Bulk In Endpoint 0x65 bLength Length of this descriptor in bytes. 0x07 0x66 bDescriptorType Endpoint descriptor type. 0x05 0x67 bEndpointAddress This is an In endpoint, endpoint number 8. 0x88 0x68 bmAttributes This is a bulk endpoint. 0x02 0x69 wMaxPacketSize (LSB) Max data transfer size. 0x6A wMaxPacketSize (MSB) 0x6B bInterval 0x40 0x00 Does not apply to FS bulk endpoints. Must be set to 0. 0x00 String Descriptor Examples (Note: The values in these strings are given as examples only and should not be used in final products. Designers are encouraged to modify the string values to reflect the final product, since they are what users will see with their operating systems.) USB String Descriptor–Index 0 (LANGID) 0x6C bLength LANGID string descriptor length in bytes. 0x04 0x6D bDescriptorType Descriptor type. 0x03 Document #: 38-08011 Rev. *B Page 18 of 26 CY7C68300 Table 5-6. EEPROM Organization (continued) EEPROM Address Field Name 0x6E LANGID (LSB) 0x6F LANGID (MSB) Field Description Required Suggested Contents Contents Language supported. Note: See http://www.usb.org for LANGID documentation (the code for English is 0x0409). 0x09 0x04 USB String Descriptor–Manufacturer 0x70 bLength String descriptor length in bytes (including bLength). 0x71 bDescriptorType Descriptor type. 0x72 bString Unicode character. 0x73 bString (“NUL”) 0x74 bString Unicode character. 0x75 bString (“NUL”) 0x76 bString Unicode character. 0x77 bString (“NUL”) 0x78 bString Unicode character. 0x79 bString (“NUL”) 0x7A bString Unicode character. 0x7B bString (“NUL”) 0x7C bString Unicode character. 0x7D bString (“NUL”) 0x7E bString Unicode character. 0x7F bString (“NUL”) 0x80 bString Unicode character. 0x81 bString (“NUL”) 0x82 bString Unicode character. 0x83 bString (“NUL”) 0x84 bString Unicode character. 0x85 bString (“NUL”) 0x86 bString Unicode character. 0x87 bString (“NUL”) 0x88 bString Unicode character. 0x89 bString (“NUL”) 0x8A bString Unicode character. 0x8B bString (“NUL”) 0x8C bString Unicode character. 0x8D bString (“NUL”) 0x8E bString Unicode character. 0x8F bString (“NUL”) 0x90 bString Unicode character. 0x91 bString (“NUL”) 0x92 bString Unicode character. 0x93 bString (“NUL”) 0x94 bString Unicode character. 0x95 bString (“NUL”) 0x96 bString Unicode character. 0x97 bString (“NUL”) Document #: 38-08011 Rev. *B 0x2C 0x03 “C” 0x43 0x00 “y” 0x79 0x00 “p” 0x70 0x00 “r” 0x72 0x00 “e” 0x65 0x00 “s” 0x73 0x00 “s” 0x73 0x00 “ ” 0x20 0x00 “S” 0x53 0x00 “e” 0x65 0x00 “m” 0x6D 0x00 “i” 0x69 0x00 “c” 0x63 0x00 “o” 0x6F 0x00 “n” 0x6E 0x00 “d” 0x64 0x00 “u” 0x75 0x00 “c” 0x63 0x00 “t” 0x74 0x00 Page 19 of 26 CY7C68300 Table 5-6. EEPROM Organization (continued) EEPROM Address 0x98 Field Name bString Field Description Required Suggested Contents Contents Unicode character. 0x99 bString (“NUL”) 0x9A bString Unicode character. 0x9B bString (“NUL”) “o” 0x6F 0x00 “r” 0x72 0x00 USB String Descriptor–Product 0x9C bLength String descriptor length in bytes (including bLength). 0x9D bDescriptorType Descriptor type. 0x9E bString Unicode character. 0x9F bString (“NUL”) 0xA0 bString Unicode character. 0xA1 bString (“NUL”) 0xA2 bString Unicode character. 0xA3 bString (“NUL”) 0xA4 bString Unicode character. 0xA5 bString (“NUL”) 0xA6 bString Unicode character. 0xA7 bString (“NUL”) 0xA8 bString Unicode character. 0xA9 bString (“NUL”) 0xAA bString Unicode character. 0xAB bString (“NUL”) 0xAC bString Unicode character. 0xAD bString (“NUL”) 0xAE bString Unicode character. 0xAF bString (“NUL”) 0xB0 bString Unicode character. 0xB1 bString (“NUL”) 0xB2 bString Unicode character. 0xB3 bString (“NUL”) 0xB4 bString Unicode character. 0xB5 bString (“NUL”) 0xB6 bString Unicode character. 0xB7 bString (“NUL”) 0xB8 bString Unicode character. 0xB9 bString (“NUL”) 0xBA bString Unicode character. 0xBB bString (“NUL”) 0xBC bString Unicode character. 0xBD bString (“NUL”) 0xBE bString Unicode character. 0xBF bString (“NUL”) 0xC0 bString Unicode character. 0xC1 bString (“NUL”) Document #: 38-08011 Rev. *B 0x2C 0x03 “U” 0x55 0x00 “S” 0x53 0x00 “B” 0x42 0x00 “2” 0x32 0x00 “.” 0x2E 0x00 “0” 0x30 0x00 “ ” 0x20 0x00 “S” 0x53 0x00 “t” 0x74 0x00 “o” 0x6F 0x00 “r” 0x72 0x00 “a” 0x61 0x00 “g” 0x67 0x00 “e” 0x65 0x00 “ ” 0x20 0x00 “D” 0x44 0x00 “e” 0x65 0x00 “v” 0x76 0x00 Page 20 of 26 CY7C68300 Table 5-6. EEPROM Organization (continued) EEPROM Address 0xC2 Field Name bString Field Description Required Suggested Contents Contents Unicode character. 0xC3 bString (“NUL”) 0xC4 bString Unicode character. 0xC5 bString (“NUL”) 0xC6 bString Unicode character. 0xC7 bString (“NUL”) “i” 0x69 0x00 “c” 0x63 0x00 “e” 0x65 0x00 USB String Descriptor–Serial Number (Note: The USB Mass Storage Class requires a unique serial number in each device. Not providing a unique serial number will crash the operating system. The serial number must be at least a minimum size of 12 characters. Some hosts will only treat the last 12 characters of the serial number as unique.) 0xC8 bLength String descriptor length in bytes (including bLength). 0xC9 bDescriptor Type Descriptor type. 0xCA bString Unicode character. 0xCB bString (“NUL”) 0xCC bString Unicode character. 0xCD bString (“NUL”) 0xCE bString Unicode character. 0xCF bString (“NUL”) 0xD0 bString Unicode character. 0xD1 bString (“NUL”) 0xD2 bString Unicode character. 0xD3 bString (“NUL”) 0xD4 bString Unicode character. 0xD5 bString (“NUL”) 0xD6 bString Unicode character. 0xD7 bString (“NUL”) 0xD8 bString Unicode character. 0xD9 bString (“NUL”) 0xDA bString Unicode character. 0xDB bString (“NUL”) 0xDC bString Unicode character. 0xDD bString (“NUL”) 0xDE bString Unicode character. 0xDF bString (“NUL”) 0xE0 bString Unicode character. 0xE1 bString (“NUL”) 0xE2 bString Unicode character. 0xE3 bString (“NUL”) 0xE4 bString Unicode character. 0xE5 bString (“NUL”) 0xE6 bString Unicode character. 0xE7 bString (“NUL”) 0xE8 bString Unicode character. 0xE9 bString (“NUL”) Document #: 38-08011 Rev. *B 0x22 0x03 “1” 0x31 0x00 “2” 0x32 0x00 “3” 0x33 0x00 “4” 0x34 0x00 “5” 0x35 0x00 “6” 0x36 0x00 “7” 0x37 0x00 “8” 0x38 0x00 “9” 0x39 0x00 “0” 0x30 0x00 “A” 0x41 0x00 “B” 0x42 0x00 “C” 0x43 0x00 “D” 0x44 0x00 “E” 0x45 0x00 “F” 0x46 0x00 Page 21 of 26 CY7C68300 Table 5-6. EEPROM Organization (continued) EEPROM Address 0xEA to 0xFF 6.0 Field Name Unused ROM Space Required Suggested Contents Contents Field Description Amount of unused ROM space will vary depending on strings. 0xFF Absolute Maximum Ratings Storage Temperature ............................................................................................................................................–65°C to +150°C Ambient Temperature with power supplied ..............................................................................................................0°C to +55.4°C Supply Voltage to Ground Potential ......................................................................................................................... –0.5V to +4.0V DC Input Voltage to Any Input Pin ......................................................................................................................................... 5.25V DC Voltage Applied to Outputs in High-Z State ........................................................................................... > –0.5V to VCC + 0.5V Power Dissipation ........................................................................................................................................................... > 936 mW Static Discharge Voltage ....................................................................................................................................................... 2000V Max Output Current per IO port ............................................................................................................................................ 10 mA 7.0 Operating Conditions[5] TA (Ambient Temperature Under Bias) .......................................................................................................................0°C to +70°C Supply Voltage .........................................................................................................................................................+3.0V to +3.6V Ground Voltage ........................................................................................................................................................................... 0V Fosc (Oscillator or Crystal Frequency) .............................................................................................................. 24 MHz ± 100 ppm ............................................................................................................................................................................ Parallel Resonant 8.0 DC Characteristics Parameter Description Conditions VCC Supply Voltage VIH Input High Voltage VIL Input Low Voltage II Input Leakage Current VOH Output Voltage High IOUT = 4 mA VOL Output Voltage Low IOUT = –4 mA Min. Typ. 3.0 3.3 2 –0.5 0 < VIN < VCC Max. Unit 3.6 V 5.25 V 0.8 V + 10 µA 2.4 V 0.4 V IOH Output Current High 4 mA IOL Output Current Low 4 mA CIN Input Pin Capacitance All but D+/D– 10 pF Only D+/D– 15 pF ICC Supply Current USB High Speed 235 260 mA ICC Supply Current USB Full Speed 90 150 mA 9.0 9.1 AC Electrical Characteristics USB Transceiver Complies with the USB 2.0 specification. 9.2 ATA Timing The ATA interface supports ATA PIO modes 0, 3, and 4, and Ultra DMA modes 2 and 4 per the ATA Specification T13/1410D Rev. 3B. Note: 5. If an alternate clock source is input on XTALIN it must be supplied with standard 3.3V signaling characteristics and XTALOUT must be left floating. Document #: 38-08011 Rev. *B Page 22 of 26 CY7C68300 10.0 Ordering Information Part Number CY7C68300 CY7C68300 CY4615 11.0 Package Type 56 SSOP 56 QFN EZ-USB AT2 Reference Design Kit Package Diagrams Figure 11-1. 56-lead Shrunk Small Outline Package 056 51-85062-*C 56-lead QFN (8 x 8 mm) 51-85144-*B Figure 11-2. 56-lead Quad Flatpack No Lead (8 x 8 mm) LF56 Document #: 38-08011 Rev. *B Page 23 of 26 CY7C68300 12.0 PCB Layout Recommendations The following recommendations should be followed to ensure reliable high-performance operation. • At least a four-layer impedance controlled boards are required to maintain signal quality. • Specify impedance targets (ask your board vendor what they can achieve). • To control impedance, maintain trace widths and trace spacing. • Minimize stubs to minimize reflected signals. • Connections between the USB connector shell and signal ground must be done near the USB connector. • Bypass/flyback caps on VBus, near connector, are recommended. • DPLUS and DMINUS trace lengths should be kept to within 2 mm of each other in length, with preferred length of 20-30mm. • Maintain a solid ground plane under the DPLUS and DMINUS traces. Do not allow the plane to be split under these traces. • It is preferred is to have no vias placed on the DPLUS or DMINUS trace routing. • Isolate the DPLUS and DMINUS traces from all other signal traces by no less than 10 mm. Source for recommendations: • EZ-USB FX2™ PCB Design Recommendations, http:///www.cypress.com/cfuploads/support/app_notes/FX2_PCB.pdf. • High-speed USB Platform Design Guidelines, http://www.usb.org/developers/data/hs_usb_pdg_r1_0.pdf. 13.0 Quad Flat Package No Leads (QFN) Package Design Notes Electrical contact of the part to the Printed Circuit Board (PCB) is made by soldering the leads on the bottom surface of the package to the PCB. Hence, special attention is required to the heat transfer area below the package to provide a good thermal bond to the circuit board. A Copper (Cu) fill is to be designed into the PCB as a thermal pad under the package. Heat is transferred from the AT2 through the device’s metal paddle on the bottom side of the package. Heat from here is conducted to the PCB at the thermal pad. It is then conducted from the thermal pad to the PCB inner ground plane by a 5 x 5 array of Via. A Via is a plated through-hole in the PCB with a finished diameter of 13 mil. The QFN’s metal die paddle must be soldered to the PCB’s thermal pad. Solder mask is placed on the board top side over each Via to resist solder flow into the Via. The mask on the top side also minimizes outgassing during the solder reflow process. For further information on this package design please refer to the application note “Surface Mount Assembly of AMKOR’s MicroLeadFrame (MLF) Technology.” This application note can be downloaded from AMKOR’s website from the following URL http://www.amkor.com/products/notes_papers/MLF_AppNote_0301.pdf. The application note provides detailed information on board mounting guidelines, soldering flow, rework process, etc. Figure 13-1 below display a cross-sectional area underneath the package. The cross section is of only one via. The solder paste template needs to be designed to allow at least 50% solder coverage. The thickness of the solder paste template should be 5 mil. It is recommended that “No Clean”, type 3 solder paste is used for mounting the part. Nitrogen purge is recommended during reflow. 0.017” dia Solder Mask Cu Fill Cu Fill PCB Material Via hole for thermally connecting the QFN to the circuit board ground plane. 0.013” dia PCB Material This figure only shows the top three layers of the circuit board: Top Solder, PCB Dielectric, and the Ground Plane Figure 13-1. Cross-Section of the Area Underneath the QFN Package Figure 13-2 is a plot of the solder mask pattern and Figure 13-3 displays an X-Ray image of the assembly (darker areas indicate solder.) Document #: 38-08011 Rev. *B Page 24 of 26 CY7C68300 Figure 13-2. Plot of the Solder Mask (White Area) Figure 13-3. X-ray Image of the Assembly 14.0 Other Design Considerations Certain design considerations must be followed to ensure proper operation of the EZ-USB AT2. The following items should be taken into account when designing a USB device with the EZ-USB AT2. 14.1 Proper Power-up Sequence Power must be applied to the EZ-USB AT2 before, or at the same time as the ATA/ATAPI device. If power is supplied to the drive first, the EZ-USB AT2 will start up in an undefined state. Designs that utilize separate power supplies for the EZ-USB AT2 and the ATA/ATAPI device are not recommended. 14.2 IDE Removable Media Devices The EZ-USB AT2 does not fully support IDE removable media devices. Changes in media state are not reported to the operating system so users will be unable to eject/reinsert media properly. This may result in lost or corrupted data. 14.3 Devices With Small Buffers The size of the ATA/ATAPI device’s buffer can greatly affect the overall data transfer performance. Care should be taken to ensure that devices have large enough buffers to handle the flow of data to/from the drive. The exact buffer size needed depends on a number of variables, but a good rule of thumb is: (aprox min buffer size) = (data rate) * (seek time + rotation time + other) where (other) may include things like time to switch heads, power-up a laser, etc. Devices with buffers that are too small to handle the extra data may perform considerably slower than expected. 14.4 USB Idle Mode When the AT2 detects a lack of USB activity from the host, it enters an idle mode and waits for USB host activity to resume. While in this idle mode, the core logic is still functioning and power consumption remains at its active level. Because of this, the AT2 is not intended for use in battery or bus powered designs. Also, care should be taken to ensure that the AT2 does not draw power from VBUS, since such a design will not meet USB specifications for standby current. 15.0 Disclaimers, Trademarks, and Copyrights Purchase of I2C components from Cypress, or one of its sublicensed Associated Companies, conveys a license under the Philips I2C Patent Rights to use these components in an I2C system, provided that the system conforms to the I2C Standard Specification as defined by Philips. EZ-USB AT2 is a trademark, and EZ-USB is a registered trademark, of Cypress Semiconductor. All product and company names mentioned in this document are the trademarks of their respective holders. Document #: 38-08011 Rev. *B Page 25 of 26 © Cypress Semiconductor Corporation, 2002. The information contained herein is subject to change without notice. Cypress Semiconductor Corporation assumes no responsibility for the use of any circuitry other than circuitry embodied in a Cypress Semiconductor product. Nor does it convey or imply any license under patent or other rights. Cypress Semiconductor does not authorize its products for use as critical components in life-support systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress Semiconductor products in life-support systems application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress Semiconductor against all charges. CY7C68300 Document History Page Description Title: CY7C68300 EZ-USB AT2™ USB 2.0 to ATA/ATAPI Bridge Document Number: 38-08011 REV. ECN NO. Issue Date Orig. of Change Description of Change ** 111608 05/15/02 BHA New Data Sheet *A 116660 08/30/02 BHA Added new 56-pin Quad Flatpack No Lead package and pinout. Revised pin description table to reflect new package. Added typical reset diagram. Removed Advance Information. *B 121518 12/17/02 GIR Added section regarding idle current. Removed Isup row in power table. Revised PCB layout section. Document #: 38-08011 Rev. *B Page 26 of 26