USB 2.0
Datasheet
Chapter 5 Pin Descriptions
This chapter is organized by a set of pin configurations (organized by package type) followed by a corresponding pin list organized alphabetically. A comprehensive and detailed description list of each signal (named in the pin list) is organized by function in Table 5.2, “USB251x Pin Descriptions,” on page 22. Please refer to Table 5.3, “Buffer Type Descriptions,” on page 27 for a list of buffer types.
The “N” symbol in the signal name indicates that the active, or asserted, state occurs when the signal is at a low voltage level. When “N” is not present after the signal name, the signal is asserted when it is at the high voltage level. The terms assertion and negation are used exclusively. This is done to avoid confusion when working with a mixture of “active low” and “active high” signals. The term assert, or assertion, indicates that a signal is active, independent of whether that level is represented by a high or low voltage. The term negate, or negation, indicates that a signal is inactive.
5.1Pin Configurations and Lists (Organized by Package Type)
NC
NC
NC
SDA / SMBDATA / NON_REM[1]
VDD33
SCL / SMBCLK / CFG_SEL[0]
HS_IND / CFG_SEL[1]
RESET_N
VBUS_DET
| 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 |
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SUSP_IND / LOCAL_PWR / NON_REM[0] | 28 |
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| 18 | NC | |
VDD33 | 29 |
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| 17 | OCS_N[2] | |
USBDM_UP | 30 |
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| SMSC |
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| 16 | PRTPWR[2] / BC_EN[2]* | |||
USBDP_UP | 31 |
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| 15 | VDD33 | ||||
USB2512/12A/12B | |||||||||||
XTALOUT | 32 | 14 | CRFILT | ||||||||
USB2512i/12Ai/12Bi | |||||||||||
XTALIN / CLKIN | 33 | 13 | OCS_N[1] | ||||||||
(Top View | |||||||||||
PLLFILT | 34 | 12 | PRTPWR[1] / BC_EN[1]* | ||||||||
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| Ground Pad |
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RBIAS | 35 |
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| 11 | TEST | ||||
(must be connected to VSS) | |||||||||||
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VDD33 | 36 |
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| 10 | VDD33 | |
| 1 2 3 4 5 6 7 8 9 |
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| USBDM_DN[1] | USBDP_DN[1] | USBDM_DN[2] | USBDP_DN[2] | VDD33 | NC | NC | NC | NC |
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Indicates pins on the bottom of the device.
Figure 5.1Note: *Battery charging enable (BC_EN) is only available in the USB251xB/Bi.
Revision 1.0 | 12 | SMSC USB251x |
DATASHEET