Sim300DZ Antenna connector

Hi
i am designing schematic for sim300DZ GSM module.Please tell me how can i design schematic for antenna pad connector and impedence matching circuit.also i want to know about backup battery and charging circuit ,i am attatching my schematic for sim300DZ interface.

Thanx

hi
u can use antenna simbol on protel schematic (on protel DXP)

for charching :
sim300 has a charger circuit in itself
U just should connect a 3.7v (nickel m or c atleast 700mah) at vbat pin

Thanx sabeti for replying

sim300 has a charger circuit in itself
U just should connect a 3.7v (nickel m or c atleast 700mah) at vbat pin

Click to expand...

actually i want to use a NiCd battery pack (3.6v,700mah),but the charger given inmodule is for Li ion battery.Can i use it for NiCd battery .If so simply connect battery pack to VBAT via a limiting resistor and 5v to CHG pin.
plz give ur comment

u can use antenna simbol on protel schematic (on protel DXP)

Click to expand...

i'm using orcad.

m.waqas said:

actually i want to use a NiCd battery pack (3.6v,700mah),but the charger given inmodule is for Li ion battery.Can i use it for NiCd battery .If so simply connect battery pack to VBAT via a limiting resistor and 5v to CHG pin.
plz give ur comment

Click to expand...

SIMCom does not recommend the use of any battery chemistry other than Lion as the voltages are not compatible with the module. You cannot use the SIM300 charger for any battery other then Lion as the charging requirements are different. Also, if you do use Lion bateries you must supply the VCHG input from a current-limited supply (600mA) or you may destroy the module.

Also, if you do use Lion bateries you must supply the VCHG input from a current-limited supply (600mA) or you may destroy the module

Click to expand...

it means i have to use a battery(5v,580mAh) also for VCHG pin.

here is my power supply circuit for SIM300DZ please mention if there is problem
i need 3.3v for PIC,5v for GPS.