atr2730 ATMEL Corporation, atr2730 Datasheet - Page 8

• Manufacturer Part Number: atr2730
• Description: L-band Down-converter For Dab Receivers
• Manufacturer: ATMEL Corporation

3.12
3.13
8
Lock Detector
Test Interface
ATR2730 [Preliminary]
An internal lock detector checks if the phase difference of the input signals of the phase detector
is smaller than approximately 250 ns in seven subsequent comparisons. If a phase lock is
detected, the open collector output pin PLCK is set to HIGH. It should be noted that the output
current of this pin must be limited by external circuitry as it is not limited internally. If the voltage
at the control pin CI is chosen to be half the supply voltage, or if this control pin is left open, the
lock-detector function is deactivated and the logical value of the PLCK output is undefined.
If the input control pin CI is left open (high impedance state), a test signal, which monitors the
output frequency of the reference divider, appears at the output pin TI.
Analogous to the reference divider, a test signal monitoring the output frequency of the RF
divider appears at the test interface output pin TI, if the input control pin CI is connected to
V
Table 3-2.
CC
/2.
V
Open
GND
CC
CI
V
s
/2
Control Interface (CI) Settings
Connected to GND
200 µA
300 µA
0 µA
PD
Undefined
Undefined
PLCK
Ok
Ok
Reference divider
RF divider
TI
–
–
4903C–DAB–03/07