User's Manual

Table Of Contents
9/29/2004 OV4F2
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User Manual BCM2035
04/23/03
Broadcom Corporation
Document 2035-UM100-R Low Power Oscillator Page 25
LPO CLOCK INTERFACE
The BCM2035 can be configured for use with an external 32.768 kHz oscillator for low power operation. The
32.768 kHz clock should be connected to the LPO_IN/LPO_RES pin that can accept an analog or digital LPO
clock. The LPO_IN/LPO_RES provides a high impedance input and will not load the oscillator even when the
BCM2035 is powered down. Figure 8 shows the connectivity of BCM2035 to a 32.768 kHz oscillator in external
LPO mode.
Figure 8: BCM2035 Connectivity to 32.768 kHz Oscillator in External LPO Mode
The
BCM2035 can be configured to use the internal LPO for low power mode operation.
Figure 9 shows the proper connection for internal LPO mode.
Figure 9: BCM2035 Connectivity For Internal LPO Mode
LPO_IN/LPO_RES
BCM2035
32.768 kHz
LPO_IN/LPO_RES
BCM2035