Altec gsm socket al7024s Manuale Utente

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AL7020S, AL7024S Designer’s Guide 
 
Doc. No. DG_7024E 
Altec Electronic AG  
Seite 27 / 32 
5.1.3   Power Supply 3.3V (3V Models) 
 
A power supply with 3.3V +/- 5% (3V models) and a minimum power of 1A  is strictly 
required to supply this module. The supply-regulator should be placed as close to the 
module as possible (about 5cm or nearer). To keep a short and low impedance 
connection between the regulator and the module is very important when supplying 
the module with 3.3V.  The 3.3V-trace between regulator and module should be at 
least 2.5mm wide or better an entire layer. 
 
 
 Important: 
 
 The module draws up to 0.8A max. for 577µs every 4,6ms at GSM transmit level 
 PCL5 (2W). Therefore a regulator with fast transient response and good load   
 regulation is strongly recommended.    
 
 
 
 
 
 
 
5.1.4 Preferred Regulators 
 
 
Preferred fast response regulators: 
 
The following regulators where tested and found to be good.    
 
 
- MIC29150    
Micrel Inc. 
 
 
www.micrel.com
 
- LP3852 / LP3855  National Semiconductor 
www.national.com
 
- LM3940  
 
National Semiconductor 
www.national.com
 
- LTC1778 
 
Linear Technology 
 
www.linear.com
 
 
 
 
 
 
 
 
 
Peak 0.8 A  
Current 
Measurement  
@ PCL 5