AD6625
AD6626
In base-band power management, ADI AD6537 is designed for all base-band main power supply.
It provides seven regulator outputs for VCORE (1.8V), VMEM (2.93V), VEXT(2.93V), VRTC (1.8V), VCTCXO (2.75V), VSIM (2.85V),VMIC(2.75V).
VCORE and VMEM provide all digital power and VMEM provides all analog power. VRTC is used to charge Li-Mn coin cell for real time clock, and
VCTCXO is the power source of 13MHz clock buffer. Besides, AD6537 is also combined charge pump and hardware reset.
The following is the detailed description:
5.3.2. Microphone
The microphone is a noise canceling type to provide improved speech pick-up, noise immunity and reduced echo.
The GSM standard requires that when in handheld mode, the transmitter audio frequency response must fit within
the mask shown below:
5
(dB)
0
-5
-10
-15
100
Figure 5.11. Handheld GSM Transmit Audio Frequency Response Mask
AD6337B
Light
or
Controllers
Ram
GMSK
Filter
Filter
Filter
Filter
Battery
Charger
VCORE: 1.8 V, 80 mA
VMEM: 2.93 V, 150 mA
VEXT: 2.93 V, 170 mA
VSIM: 2.85 V, 20 mA
VRTC: 1.8 V, 200 µA
Figure 5.10. AD6537 Functional Block Diagram
ADC
DAC
DAC
DAC
DAC
ADC
ADC
Tone
DAC
ADC
Mic
8 Voltage Regulators
1,000
Frequency (Hz)
– 5-11 –
LEDs
Crystal &
Varactor
Headphones or Headset
VABB
VMIC: 2.75 V, 1 mA
VVCXO: 2.75 V, 10 mA
10,000