uaa3515a NXP Semiconductors, uaa3515a Datasheet - Page 27

• Manufacturer Part Number: uaa3515a
• Description: 900 Mhz Analog Cordless Telephone Ic
• Manufacturer: NXP Semiconductors

Philips Semiconductors
7.9.12
An internal 1.5 V bandgap voltage reference provides the voltage reference for the low battery detect circuits, the V
voltage regulator, the VB reference and all internal analog references. In inactive mode, the adjustment is disabled.
Table 17 Voltage reference adjust register
7.9.13
Test mode bits are used only for test in production and application tuning. The test bits must be set to 0 for normal
operation. Out-of-lock of synthesizers RX or TX can be monitored indirectly on pin CDLBD: the width of the ‘glitch’ that
occurs with out-of-lock gives a direct indication of the phase error on the PLL RX and/or TX. To tune the external
inductors of the RX and TX VCOs, a defined division ratio has to be programmed into the dividers, and then the image
frequency of the VCO can be read on pin CDLBD. Test mode can also be used to check the division ratio: a frequency
can be forced on the VCO or crystal pins and the programmed frequency can be read on pin CDLBD. There is a
divide-by-2 stage before the CDLBD pin, therefore all frequencies are divided-by-2. When both charge pumps are in the
high-impedance state, the VCOs can be measured as stand alone.
Table 18 Test mode register
2002 Sep 09
900 MHz analog cordless telephone IC
BIT 2
0
0
0
0
1
1
1
1
BIT 2
0
0
0
0
1
1
1
1
V
T
EST MODE
OLTAGE REFERENCE ADJUSTMENT
BIT 1
0
0
1
1
0
0
1
1
BIT 1
0
0
1
1
0
0
1
1
BIT 0
0
1
0
1
0
1
0
1
normal operation
XOR between internal signals ‘up’ and ‘down’ of the RX synthesizer
XOR between internal signals ‘up’ and ‘down’ of the TX synthesizer
XOR between internal signals ‘up’ and ‘down’ of the RX or TX synthesizers
reference divider output divided by 2
prescaler and main divider RX divided by 2
prescaler and main divider TX divided by 2
both synthesizer charge pumps are in high-impedance-state
BIT 0
0
1
0
1
0
1
0
1
27
SELECT
0
1
2
3
4
5
6
7
SELECT
NOMINAL VOLTAGE REFERENCE
1%
3%
5%
7%
7%
5%
3%
1%
Product specification
UAA3515A
REG