stmec001qtr STMicroelectronics, stmec001qtr Datasheet - Page 7

• Manufacturer Part Number: stmec001qtr
• Description: Power Interface Switch For Expresscardtm
• Manufacturer: STMicroelectronics

STMEC001
3.1
Table 3.
RCLKEN
SYSRST
Symbol
CPUSB
PERST
SHDN
CPPE
STBY
OC
Pin functional description
Pin description
A logic low level on this input indicates that the card present supports PCI Express functions. This
input pin connects to the 3.3Vaux input thru a 150Kohm internal pull-up. When inserted, the card
physically connects this input to ground if the card supports PCI Express functions
A logic low level on this input indicates that the card present supports USB functions. This input
connects to the 3.3Vaux input thru a 150KΩ internal pull-up. When inserted, the card physically
connects this input to ground if the card supports USB functions.
When asserted (logic low), STMEC001 turns off all voltage outputs and the Discharge FETs at the 3
outputs are activated.
When asserted (logic low), this input places the power switch in Standby Mode by turning off the 3.3V
and 1.5V power switches and keeping the 3.3Vaux switch on.
This pin serves as both an input and an output. On power up, the power switch keeps this signal at a
low state as long as any of the output power rails are out of their tolerance range. Once all output
power rails are within tolerance, the power switch releases RCLKEN allowing it to transition to a high
state (internally pulled up to 3.3Vaux). The transition of RCLKEN from a low to a high state starts an
internal timer for the purpose of de-asserting /PERST. As an input, RCLKEN can be kept low to delay
the start of the /PERST internal timer. RCLKEN can be used by the host system to enable a clock
driver.
On power up, this output remains asserted. Once all power rails are within tolerance, RCLKEN goes
asserted and /PERST is de-asserted after a time delay. On power down, this output is asserted
whenever any of the power rails drop below their voltage tolerance.
This input is driven by the host system and directly affects /PERST. Asserting /SYSRST (logic level:
low) forces /PERST to assert.
This is an open drain output for overcurrent indication. Output does not turn off during overcurrent
condition. The output voltage decreases as the output current exceeds overcurrent limit. Only if the
temperature increases above limit that the output is turned off completely. Overcurrent in one output
does not affect the other outputs.
Description
Pin configuration
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