Nokia 5110 Instruction De Maintenance
PAMS
Technical Documentation
NSE–1
System Module
Original 03/98
Page 3 – 50
DC Characteristics
Regulators
Transceiver has got a multi function power management IC, which con-
tains among other functions, also 7 pcs of 2.8 V regulators. All regulators
can be controlled individually with 2.8 V logic directly or through control
register. In GSM direct controls are used to get fast switching, because
regulators are used to enable RF–functions.
tains among other functions, also 7 pcs of 2.8 V regulators. All regulators
can be controlled individually with 2.8 V logic directly or through control
register. In GSM direct controls are used to get fast switching, because
regulators are used to enable RF–functions.
Use of the regulators can be seen in the power distribution diagram.
CCONT also provides 1.5 V reference voltage for PLUSSA and CRFU1a
( and for DACs and ADCs in COBBA too ).
( and for DACs and ADCs in COBBA too ).
Control Signals
All control signals are coming from MAD and they are 2.8 V logic signals.
Functional Description
RF block diagram has conventional dual conversion receiver and in trans-
mitter there is a upconversion mixer for the final TX–frequency.
mitter there is a upconversion mixer for the final TX–frequency.
Architecture contains three ICs. Most of the functions are horizontally and
vertically integrated. UHF functions except power amplifier and VCO are
integrated into CRFU_1a, which is a BiCMOS–circuit suitable for LNA–
and mixer–function. Most of the functions are in PLUSSA, which also is a
BiCMOS–circuit. PLUSSA is a IF–circuit including IQ–modulator and PLLs
for VHF– and UHF–synthesizers.
vertically integrated. UHF functions except power amplifier and VCO are
integrated into CRFU_1a, which is a BiCMOS–circuit suitable for LNA–
and mixer–function. Most of the functions are in PLUSSA, which also is a
BiCMOS–circuit. PLUSSA is a IF–circuit including IQ–modulator and PLLs
for VHF– and UHF–synthesizers.
Power amplifier is also an ASIC, it is a so called MMIC ( monolithic micro-
wave integrated circuit ). It has three amplifier stages including input and
interstage matchings. Output matching network is external. Also TX gain
control is integrated into this chip.
wave integrated circuit ). It has three amplifier stages including input and
interstage matchings. Output matching network is external. Also TX gain
control is integrated into this chip.
Frequency synthesizers
Both VCOs are locked with PLLs into stable frequency source ( see figure
3 ), which is a VCTCXO–module ( voltage controlled temperature com-
pensated crystal oscillator ). VCTCXO is running at 13 MHz. Temperature
effect is controlled with AFC ( automatic frequency control ) voltage,
VCTCXO is locked into frequency of the base station. AFC is generated
by baseband with a 11 bit conventional DAC in COBBA.
3 ), which is a VCTCXO–module ( voltage controlled temperature com-
pensated crystal oscillator ). VCTCXO is running at 13 MHz. Temperature
effect is controlled with AFC ( automatic frequency control ) voltage,
VCTCXO is locked into frequency of the base station. AFC is generated
by baseband with a 11 bit conventional DAC in COBBA.