User Manual

GM47/48 Technical description

BA/SEM/MS 02:0004 Rev B

3.4.1 Power Supply (VCC)

The VCC supplies the module with external power. Any other voltage

needed is generated internally.

Parameter Mode Limit

Voltage to be applied Nominal 3.6 Volts

Tolerance including ripple

3.4 Volts - 4.0 Volts

Over voltages 5.5 Volts

Current Drive capability at TX Full Power < 600 mA (average))

< 2 A (Peak)

GM 47/48 have not internal capacitance to supply the large current

peaks during GSM transmission. Therefore on burst transmission the

application DC source is responsible for providing the appropriate

current.

3.5 ON/OFF and External Power Signals

Pins Name Dir Description

14 ON/OFF I Square signal to turn on/off the module

34 VIO O External power supply

3.5.1 Module ON/OFF

The module is powered ON/OFF by earthing (pulling low) pin 14 as

per figure 3.2 below. The pin should then be released as it is an

internal pull up to return it to the high state.

Note: Driving with 2.75V or 3.6V is not permitted and restrict module

functionality.

Parameter Minimum Typical Maximum Units

Voltage HIGH Level (FALSE) VCC By internal

pull up only

Voltage LOW Level (TRUE) 0 0.3*VCC Volts

Pull-up Resistance Internal pull up 39

KΩ

2 Measured at system connector pins.