UC864-E Hardware User Guide
1vv0300766a Rev.1 - 31/01/08
4 Hardware Commands
4.1Turning ON the UC864-E
To turn on UC864-E, the pad ON# must be tied low for at least 1 second and then released. The maximum current that can be drained from the ON# pad is 0,1 mA.
A simple circuit to do it is:
R2
GND
NOTE: UC864-E turns fully on also by supplying power to the USB_VBUS pin (provided there's a battery on the VBATT pads). Care must be taken to avoid supplying power to the USB_VBUS pin before the module turns on.
To check if the UC864-E has powered on, the hardware line PWRMON should be monitored. When PWRMON goes high, the module has powered on.
NOTE: don't use any pull up resistor on the ON# line, it is internally pulled up. Using pull up resistor may bring to latch up problems on the UC864-E power regulator and improper power on/off of the module. The line ON# must be connected only in open collector configuration.
NOTE: In this document all the lines that are inverted, hence have active low signals are labeled with a name that ends with a "#" or with a bar over the name.
NOTE: UC864-E turns fully on also by supplying power to the Charge pad (provided there's a battery on the VBATT pads).
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