I have interfaced l80 gps module to my pic24f microcontroller . This controller works under 3.3v and gps at 3.3v . The total current consumption is 27 to 28 mA it takes . After sending the command as per datasheet suggested for stand-by mode it should take 1mA only but it is consuming 13.35mA,totally after making my controller to sleep mode and disable the interrupt ,adc and timer. My schematic for gps is GPS

Schematic supplied by datasheetenter image description here

And in datasheet it is suggested that enter image description here

They have mentioned in the above diagram if vcc and battery backup tied to vcc the backup and standby modes are not supported.Totally it should take less than or equal to 2mA. What is the problem between the quectel schematic and my schematic design ? How can i solve this issue?. Power supply schematic enter image description here

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    \$\begingroup\$ Two questions: how do you generate the 3.3V supply? And where is the current measured? \$\endgroup\$ – Edesign Nov 8 '16 at 9:15
  • \$\begingroup\$ @Edesign 12v ip to regulator from battery to regulators LM2576 and 3.8v from first reg to LMS1117 regulator 3.3v output. Current measured at the ip of supply through multi-meter... \$\endgroup\$ – Pradeep kumark Nov 8 '16 at 9:37
  • \$\begingroup\$ Sorry, I can't understand your answer. Could you add a simplified schematics instead? \$\endgroup\$ – Edesign Nov 8 '16 at 9:49
  • \$\begingroup\$ @Edesign Added power supply schematic... \$\endgroup\$ – Pradeep kumark Nov 8 '16 at 10:15
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    \$\begingroup\$ Thank you for the schematic. If you measure the current at CN4, how can you be sure that it is the GPS which is consuming the extra current? What else do you have? \$\endgroup\$ – Edesign Nov 8 '16 at 10:16

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