AK2400 Datasheet, PDF (23/52 Pages) Asahi Kasei Microsystems – High integrated receiver for PMR-LMR

[AK2400]
LD : Selects analog or digital for the lock detect.
0 : Digital Lock Detect
1 : Analog Lock Detect
CPPOLA : Selects positive or negative output polarity for Charge Pump1 and Charge Pump2.
0 : Positive
1 : Negative
PRE[1:0] : Selects a dividing ratio for the prescaler.
“00” : P=4
“01” : P=8
“10” : P=16
“11” : P=16
R1[7:0] : Sets a dividing ratio for the reference clock.
This can be set in the range from 3 (3 divisions) to 255 (255 divisions). 0 to 2 cannot be set.
Address 0x04
FASTEN : Enables or disables the Fast Lockup mode. FAST
0 : The switchover settings specified in CP2[2:0] and FAST[12:0] are disabled.
1 : The switchover settings specified in CP2[2:0] and FAST[12:0] are enabled.
CP2[2:0] : Sets the current value for the charge pump for the Fast Lockup mode
(Charge Pump 2).
Charge Pump 2 current is determined by the following formula:
CP2_min = 0.57 / Resistance connected to the [BIAS] pin
Charge Pump 2 current = CP2_min × (CP2 setting + 4) [mA]
CP2[2:0]
000
001
010
011
100
101
110
111
Charge Pump 2 current [mA]
33kΩ
27 kΩ
22 kΩ
0.69
0.84
1.04
0.86
1.06
1.30
1.04
1.27
1.55
1.21
1.48
1.81
1.38
1.69
2.07
1.55
1.90
2.33
1.73
2.11
2.59
1.90
2.32
2.85
FAST[12:0] : Sets the FAST counter value.
A decimal number from 1 to 8191 can be set. This counter value is used to set the time
period during which the charge pump for the Fast Lockup mode is ON.
The charge pump for the Fast Lockup mode is turned OFF after the time period calculated
by [this count value x phase detector frequency cycle]. 0 cannot be set.
Address 0x05
VTSEL[1:0] :Sets the noise detection level of noise squelch circuit.
00：0.4V/0.5V (default) 01：0.8V/0.9V
10：1.1V/1.2V
11：1.4V/1.5V
014008989-E-01
23
2015/4