UMA1020AM Datasheet, PDF (7/20 Pages) NXP Semiconductors – Low-voltage dual frequency synthesizer for radio telephones

Philips Semiconductors
Low-voltage dual frequency
synthesizer for radio telephones
Product specification
UMA1020AM
Table 4 Fast and normal charge pumps current ratio (note 1)
CR1
0
0
1
1
CR0
0
1
0
1
I_CPA
4 × I_SET
4 × I_SET
4 × I_SET
4 × I_SET
I_CPP
4 × I_SET
4 × I_SET
2 × I_SET
2 × I_SET
Note
1. I_SET = _R--V---e-¹--_x4--_t ; common bias current for charge pumps.
Table 5 Power-down modes
AOFF
1
1
1
0
0
0
POFF
1
0
0
1
0
0
FAST
X
0
1
X
0
1
PRINCIPAL
DIVIDERS
OFF
ON
ON
OFF
ON
ON
AUXILIARY
DIVIDERS
OFF
OFF
OFF
ON
ON
ON
I_CPPF
16 × I_SET
32 × I_SET
24 × I_SET
32 × I_SET
PUMP
CPA
OFF
OFF
OFF
ON
ON
ON
I_CPPF : I_CPP
4:1
8:1
12 : 1
16 : 1
PUMP
CPP
OFF
ON
ON
OFF
ON
ON
PUMP
CPPF
OFF
OFF
ON
OFF
OFF
ON
Power-down modes
The action of the control inputs on the state of internal
blocks is defined by Table 5.
Note that in Table 5, POFF and AOFF can be either the
software or hardware power-down signals. The dividers
are ON when both hardware and software power-down
signals are at logic 0.
When either synthesizer is reactivated after power-down
the main and reference dividers of that synthesizer are
synchronized to avoid the possibility of random phase
errors on power-up.
1995 Jul 06
7