Figure 39: Power Down Mode - SimCom SIM548C HD V1.01 Hardware Design

SIM548C Hardware Design
6.4.2.1 Power down Mode
The circuit of this mode is shown in the figure:

Figure 39: Power Down mode

When the user wants to save more current consumption of the GPS part, he can pull down the
POWER_CTRL of the MCU to stop the LDO outputting. And this operation will cut off the
power of the GPS part. Note that the GPS_VRTC must be kept on.
6.4.2.2 Push-To-Fix mode
The circuit of this mode is shown in figure 40.
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SIM548C_HD_V1.01 09.05.2008