AKM AK1542A

[AK1542A]
AK1542A
20 to 600MHz Integer-N Frequency Synthesizer
1. Overview
Consisting a highly accurate charge pump that supports current adjustment in 9 steps, a reference divider, a programmable
divider and a dual-modulus prescaler (P/P+1), the AK1542A provides high performance, low consumption current and small
footprint for a wide range of frequency conversions . This synthesizer also has two general-purpose output pins which allow it
to be used to control the RF front end.
An ideal Phase Locked Loop (PLL) can be achieved by combining the AK1542A with the external loop filter and VCO (Voltage
Controlled Oscillator). Access to the registers is controlled via a 3-wire serial interface. The operating supply voltage is from
2.7 to 5.5V; and the supply voltage for the charge pump and that for the serial interface can be driven separately.
2. Features

Operating frequency:

Programmable charge pump current:
20 to 600MHz
158 to 2528A typical
The charge pump current can be changed in 9 steps; and the current
range can be adjusted by the external resistance.
Two current settings can be specified with the register and switched
over from one to another using the timer.

Supply Voltage:
2.7 to 5.5 V (PVDD pin)

Separate power supply for the charge pump:
PVDD to 5.5V (CPVDD pin)

On-chip power-saving features

On-chip lock detection feature of PLL:
Direct output to the PFD (Phase frequency detector)
or digital filtering output can be selected.

General-purpose output:
It has two general-purpose output ports to control peripheral parts.

Very low consumption current:
2.2mA typical

Package:
24pin QFN (0.5mm pitch, 4mm4mm0.75mm)

Operating temperature:
-40C to 85C
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Table of Contents
1.
Overview ___________________________________________________________________________ 1
2.
Features ___________________________________________________________________________ 1
3.
Block Diagram _______________________________________________________________________ 3
4.
Pin Functional Description ____________________________________________________________ 4
5.
Absolute Maximum Ratings ___________________________________________________________ 6
6.
Recommended Operating Range _______________________________________________________ 6
7.
Electrical Characteristics ______________________________________________________________ 7
8.
Block Functional Descriptions ________________________________________________________ 11
9.
Register Map _______________________________________________________________________ 18
10.
Register Function Description ________________________________________________________ 20
11.
IC Interface Schematic _______________________________________________________________ 27
12.
Recommended Schematic for Off-Chip Component _______________________________________ 29
13.
Power-up Sequence _________________________________________________________________ 31
14.
Typical Evaluation Board Schematic ___________________________________________________ 33
15.
Block Diagram by Power Supply_______________________________________________________ 34
16.
Outer Dimensions___________________________________________________________________ 35
17.
Marking ___________________________________________________________________________ 36
In this specification (draft version), the following notations are used for specific signal and register names:
[Name]: Pin name
<Name>: Register group name (Address name)
{Name}: Register bit name
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[AK1542A]
CPVSS
CPVDD
PVDD
PVSS
VREF
DVSS
3. Block Diagram
LDO
BIAS
R COUNTER
14 bit
REFIN
CP
CHARGE
PUMP
PHASE
FREQENCY
DETECTOR
CLK
CPZ
REGISTER
24 bit
DATA
LE
LOCK DETECT
SWALLOW
COUNTER
6 bit
FAST
COUNTER
PROGRAMABLE
COUNTER
13 bit
SWIN
N DIVIDER
GPO2
GPO1
8/9,16/17,32/33
PDN2
-
PDN1
RFINN
LD
TEST3
PRESCALER
TEST2
+
TEST1
RFINP
Fig. 1 Block Diagram
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4. Pin Functional Description
Table 1 Pin Functions
No.
Name
1
CPVDD
P
Power supply for charge pump
2
TEST3
DI
Test pin 3, This pin must be connected to ground.
3
TEST1
DI
Test pin 1, This pin must be connected to ground.
4
LE
DI
Load enable
Schmidt trigger input
5
DATA
DI
Serial data input
Schmidt trigger input
6
CLK
DI
Serial clock
Schmidt trigger input
7
LD
DO
Lock detect
8
PDN2
DI
Power down pin for PLL
Schmidt trigger input
9
PDN1
DI
Power down signal for LDO
Schmidt trigger input
10
REFIN
AI
Reference input
11
TEST2
DI
Test pin 2, This pin must be connected to ground.
12
GPO1
DO
General-purpose output pin 1
“Low”
13
GPO2
DO
General-purpose output pin 2
“Low”
14
DVSS
G
Digital ground pin
15
VREF
AO
Connect to LDO reference voltage capacitor
16
RFINN
AI
Prescaler input
17
RFINP
AI
Prescaler input
18
PVDD
P
Power supply for peripherals
19
BIAS
AIO
Resistance pin for setting charge pump current
20
PVSS
G
Ground pin for peripherals
21
CP
AO
Charge pump output
22
CPZ
AIO
Connect to the loop filter capacitor
Notes 1) & 2)
23
SWIN
AI
Connect to resistance pin for fast Lock Up
Notes 1) & 2)
24
CPVSS
G
Ground pin for charge pump power supply
Note 1)
I/O
Pin Functions
Power down
Remarks
Internal pull-down,
Schmidt trigger input
Internal pull-down,
Schmidt trigger input
“Low”
Internal pull-down,
Schmidt trigger input
“Low”
“Hi-Z”
For detailed functional descriptions, see the section “Charge Pump and Loop Filter” in “8. Block Functional
Descriptions”.
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Note 2)
The input voltage from the [CPZ] pin is used in the internal circuit. The [CPZ] pin must not be open even when the
fast Lock Up feature is unused.
For the output destination from the [CPZ] pin, see “P.12 Fig.5 Loop Filter Schematic”. The [SWIN] pin could be
open when the fast Lock Up feature is not used.
Note 3)
Power down refers to the state where [PDN1]=[PDN2]=”Low” after power-on.
Note 4)
TEST1 to 3 must be connected to ground.
BIAS
G: Ground pin
PVSS
P: Power supply pin
CP
DO: Digital output pin
DI: Digital input pin
CPZ
AIO: Analog I/O pin
SWIN
AO: Analog output pin
CPVSS
AI: Analog input pin
24
23
22
21
20
19
CPVDD
1
18 PVDD
TEST3
2
17 RFINP
TEST1
3
LE
4
DATA
5
14 DVSS
CLK
6
13 GPO2
16 RFINN
TOP
10
11
12
TEST2
GPO1
9
15 VREF
REFIN
8
PDN1
LD
7
PDN2
VIEW
Fig. 2 Package Pin Layout
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5. Absolute Maximum Ratings
Table 2 Absolute Maximum Ratings
Parameter
Symbol
Min.
Max.
Unit
Remarks
VDD1
-0.3
6.5
V
Note 1), Applied to [PVDD] pin
VDD2
-0.3
6.5
V
Note 1), Applied to [CPVDD] pin
VSS1
0
0
V
Voltage ground level, applied to [PVSS] pin
VSS2
0
0
V
Voltage ground level, applied to [CPVSS] pin
VSS3
0
0
V
Voltage ground level, applied to [DVSS] pin
VAIN1
VSS1-0.3
VDD1+0.3
V
Notes 1) & 2)
VAIN2
VSS2-0.3
VDD2+0.3
V
Notes 1) & 3)
Digital Input Voltage
VDIN
VSS3-0.3
VDD1+0.3
V
Notes 1) & 4)
Input Current
IIN
-10
10
mA
Storage Temperature
Tstg
-55
125
°C
Supply Voltage
Ground Level
Analog Input Voltage
Note 1)
0V reference for all voltages.
Note 2)
Applied to [REFIN], [RFINN] and [RFINP] pins.
Note 3)
Applied to [CPZ] and [SWIN] pins.
Note 4)
Applied to [CLK], [DATA], [LE], [PDN1], [PDN2], [TEST1], [TEST2] and [TEST3] pins.
Exceeding these maximum ratings may result in damage to the AK1542A. Normal operation is not guaranteed at these
extremes.
6. Recommended Operating Range
Table 3 Recommended Operating Range
Parameter
Operating Temperature
Symbol
Min.
Ta
-40
VDD1
2.7
VDD2
VDD1
Typ.
Max.
Unit
Remarks
85
C
3.3
5.5
V
Applied to [PVDD] pin
5.0
5.5
V
Applied to [CPVDD] pin
Supply Voltage
Note 1)
VDD1 and VDD2 can be driven individually within the recommended operating range.
The specifications are applicable within the recommended operating range (supply voltage /operating temperature).
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7. Electrical Characteristics
1. Digital DC Characteristics
Table 4 Digital DC Characteristics
Parameter
Symbol
Conditions
Min.
High level input voltage
Vih
Low level input voltage
Vil
High level input current 1
Iih1
Vih = VDD1=5.5V
-1
High level input current 2
Iih2
Vih = VDD1=5.5V
27
Low level input current
Iil
Vil = 0V, VDD1=5.5V
-1
High level output voltage
Voh
Ioh = -500µA
Low level output voltage
Vol
Iol = 500µA
Typ.
Max.
Note 1)
0.2VDD1
V
Note 1)
1
µA
Note 2)
110
µA
Note 3)
1
µA
Note 1)
V
Note 4)
V
Note 4)
VDD1-0.4
0.4
Note 1)
Applied to [CLK], [DATA], [LE], [PDN1], [PDN2], [TEST1], [TEST2] and [TEST3] pins.
Note 2)
Applied to [CLK], [DATA], [LE] , [PDN1]and [PDN2] pins.
Note 3)
Applied to [TEST1], [TEST2] and [TEST3] pins.
Note 4)
Applied to [LD], [GPO1] and [GPO2] pins.
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Remarks
V
0.8VDD1
55
Unit
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[AK1542A]
2. Serial Interface Timing
<Write-In Timing>
Tlesu
Tle
Tcsu
LE
(Input)
Tch
Tcl
CLK
(Input)
Tsu
DATA
(Input)
D19
Thd
D0
D18
A3
A2
A1
A0
D19
Fig. 3 Serial Interface Timing
Table 5 Serial Interface Timing
Parameter
Symbol
Min.
Typ.
Max.
Unit
Clock L level hold time
Tcl
40
ns
Clock H level hold time
Tch
40
ns
Clock setup time
Tcsu
20
ns
Data setup time
Tsu
20
ns
Data hold time
Thd
20
ns
LE Setup Time
Tlesu
20
ns
LE Pulse Width
Tle
40
ns
Remarks
Note 1) While [LE] pin is setting at “Low”, 24 iteration clocks have to be set with [CLK] pin. If 25 or larger clocks are set, the
last 24 clocks synchronized data are valid.
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3. Analog Circuit Characteristics
The resistance of 27kΩ is connected to the [BIAS] pin, VDD1=2.7 to 5.5V, VDD2=VDD1 to 5.5V, –40°C≤Ta≤85°C
Parameter
Min.
Typ.
Max.
Unit
Remarks
RF Characteristics
Input Sensitivity
Input Frequency
-15
+5
-5
+5
20
600
Input frequency ≥ 100MHz
dBm
20MH ≤ Input frequency < 100MHz
MHz
REFIN Characteristics
Input Sensitivity
0.4
2
Vpp
Input Frequency
5
40
MHz
75
MHz
3
MHz
Maximum Allowable Prescaler Output
Frequency
Phase Detector
Phase Detector Frequency
Charge Pump
Charge Pump Maximum Value
2528
µA
Charge Pump Minimum Value
158
µA
Icp TRI-STATE Leak Current
1
nA
0.7 ≤ Vcpo ≤ VDD2-0.7
Vcpo : Voltage at [CP] pin
Mismatch between Source and Sink Currents
Note 1)
10
%
Vcpo = VDD2/2, Ta=25°C
Icp vs. Vcpo
15
%
0.5 ≤ Vcpo ≤ VDD2-0.5, Ta=25°C
50
µs
Note 2)
Others
VREF Rise Time
Consumption Current
IDD1
10
µA
2.7
mA
[PDN1]=“Low”, [PDN2]=”Low"
[PDN1]=”High”,[PDN2]=”High”
IDD2
1.8
IDD for [PVDD]
[PDN1]=”High”,[PDN2]=”High”
IDD3
Note 3)
0.4
0.9
mA
IDD for [CPVDD]
[PDN1]=”High”,[PDN2]=”Low”
IDD4
0.5
1
mA
IDD for [PVDD]
Note 1) Mismatch between Source and Sink Currents: [(|Isink|-|Isource|)/{(|Isink|+|Isource|)/2}] × 100 [%]
Note 2) See “Fig. 4 Charge Pump Characteristics - Voltage vs. Current”: Icp vs. Vcpo:
[{1/2×(|I1|-|I2|)}/{1/2×(|I1|+|I2|)}]×100 [%]
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Note 3)
IDD3 doesn’t include the current depending on Phase Detector Frequency. IDD3 is the current the Charge Pump
circuit consumes constantly.
Note 4)
In the case of [PDN1]=”High” and [PDN2]=”High”, the total current consumption = IDD2 + IDD3.
Note 5)
The shipment test is done with the exposed pad at the center of backside connected to VSS.
Resistance Connected to the BIAS Pin for Setting Charge Pump Output Current
Parameter
BIAS resistance
Min.
Typ.
Max.
Unit
22
27
33
kΩ
Remarks
Icp
I1
I2
I2
I1
Isink
Isource
0.5
CPVDD/2
CPVDD-0.5
Vcpo
Fig. 4 Charge Pump Characteristics - Voltage (Vcpo) vs. Current (Icp)
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[AK1542A]
8. Block Functional Descriptions
1. Frequency Setup
The following formula is used to calculate the frequency setting for AK1542A.
Frequency setting (external VCO output frequency) = FPFD × N
N
: Dividing number N = [ (P × B) + A ]
FPFD
: Phase detector frequency FPFD = [REFIN] pin input frequency / R counter dividing number
P
: Prescaler Value (See<Address2>:{Pre[1:0]})
B
: B (Programmable) counter value (See <Address1>:{B[12:0]})
A
: A (Swallow) counter value (See <Address1>:{A[5:0]})
Calculation examples
When the [REFIN] pin input frequency is 10MHz, the phase detector frequency FPFD =5kHz and the frequency setting =
460.1MHz;
[The AK1542A Settings]
R=10000000/5000 = 2000 (<Address3> : {R[13:0]}=2000dec)
P=32 (<Address2>:{Pre[1:0]} =10bin)
B=2875 (<Address1>:{B[12:0]} =2875dec)
A=20
(<Address1>:{A[5:0]} =20dec)
Frequency setting = 5000 × [ (32×2875) + 20] = 460.1MHz
Lower limit for setting consecutive dividing numbers
In the AK1542A, it is impossible to set consecutive dividing numbers below the lower limit. The lower limit is calculated by
the following formula;
2
Nmin=P -P
For example, in the case of P=16, it can be set 240 and over as consecutive dividing numbers.
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[AK1542A]
2. Charge Pump and Loop Filter
In AK1542A, the fast Lock Up could be achieved by changing a charge pump current and enabling the loop filter. This is
called Fast Lock Up mode. For details, see ”3. Fast Lock Up Mode” on page 13.
The loop filter is external and connected to [CP], [SWIN] and [CPZ] pins. The [CPZ] pin should be connected to the R2 and
C2, which are intermediate nodes, even if the Fast Lock Up is not used. Therefore, R2 must be connected to the [CP] pin,
while C2 must be connected to the ground.
Phase Detector
Loop Filter
up
R3
CP
VCO
C1
down
R2'
R2
C3
Timer
SWIN
C2
CPZ
Fig. 5 Loop Filter Schematic
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[AK1542A]
3. Fast Lock Up Mode
Setting D[16]={FASTEN} in <Address4> to 1 enables the Fast Lock Up mode for AK1542A.
Changing a frequency setting (The frequency is changed at the rising edge of [LE] when <Address1> and <Address2> are
accessed.) or [PDN2] pin is set from ”Low” to ”High” with {FASTEN}=1 enables the Fast Lock Up mode. The loop filter switch
turns ON during the timer period specified by the counter value in D[12:0] = {FAST[12:0]} in <Address4>, and the charge
pump for the Fast Lock Up mode (Charge Pump 2) set by D[9:6] = {CP2[3:0]} in <Address2> is enabled.
After the timer period elapsed, the loop filter switch turns OFF, the charge pump for normal operation (Charge Pump 1) set by
D[3:0] = {CP1[3:0]} in <Address2> is enabled and thus normal operation returns.
The register D[12:0] = {FAST[12:0]} in <Address4> is used to set the timer period for this mode. The following formula is used
to calculate the time period:
Phase detector frequency cycle × counter value set in {FAST[12:0]}
The charge pump current could be adjusted with 9 steps for both normal operation (Charge Pump 1) and the Fast Lock Up
operation (Charge Pump 2).
The absolute value of the charge pump current is determined by the Resistor value connected to the [BIAS] pin. The following
formula shows the relationship between the resistance value, the register setting and the electric current value.
Charge pump minimum current (Icp_min) [A] = 8.55 / Resistance connected to the [BIAS] pin (Ω)
Charge pump current [A] = Icp_min [A] × (CP1 or CP2 setting + 1)
The allowed range value for the resistance connected to the [BIAS] pin is from 22 to 33 [kΩ]. For details of current settings,
see ”Register Functional Description”.
Fast lock up time specified
by the timer
Operation mode
Charge pump
Lop filter switch
Normal
Fast Lock Up Mode
Normal
Charge Pump 1
Charge Pump 2
Charge Pump 1
OFF
ON
OFF
The frequency is changed or [PDN2] pin is set to ”High” when D[16]={FASTEN}
in <Address4> is set to”1”.
Fig. 6 Timing Chart for Fast Lock Up Mode
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[AK1542A]
4. Lock Detect (LD) Signal
In AK1542A, the lock detect output can be selected by D[13] = {LD} in <Address4>. When D[13] is set to “1", the phase
detector outputs provide a phase detection as an analog level (comparison result). This is called “analog lock detect”.
When D[13] is set to “0”, the lock detect signal is output according to the internal logic. This is called “digital lock detect”.
4.1 Analog Lock Detect
In analog lock detect, the phase detector output comes from the LD pin.
Reference clock
PFD clock
VCO divide clock
Phase detector output
LD output
Fig. 7 Analog Lock Detect Operation
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4.2 Digital Lock Detect
In the digital lock detect, the [LD] pin outputs is ”Low” every time when the frequency is set. And the [LD] pin outputs “High”
(which means the locked state) when a phase error smaller than T is detected for N times consecutively. If the phase error
larger than T is detected for N times consecutively when the [LD] pin outputs “High”, the [LD] pin outputs “Low”(which means
the unlocked state).
The threshold counts for lock detection N could be set by D[18:17]={LDCNTSEL[1:0]} in <Address4>.
{LDCNTSEL[1:0]} settings and corresponding counts (N) are as follows:
00: N = 7
01: N = 15
10: N = 31
11: N = 63
The lock detect signal is shown below:
Reference clock
PFD clock
VCO divide clock
Phase detector output
Invalid
Invalid
Valid
Invalid
Valid
When “Invalid” is detected consecutively
for N times, LD outputs “High”
LD output
Fig. 8
Digital Lock Detect Operations
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[AK1542A]
Unlock(LD=”Low”
)
Flag=0
No
Phase Error < T
Yes
Flag=Flag+1
No
Flag>N
Yes
Lock(LD=”High”)
Fig. 9 Transition Flow Chart: Unlock State to Lock State
Lock(LD=”High”)
Address2 write
Flag=0
No
Phase Error > T
Yes
Flag=Flag+1
No
Flag>N
Yes
Unlock(LD=”Low”)
Fig. 10 Transition Flow Chart: Lock State to Unlock State
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[AK1542A]
5. Reference Input
The reference input could be set to a dividing number in the range of 4 to 16383 using {R[13:0]}, which is a 14-bit address of
D[13:0] in <Address3>. A dividing number from 0 to 3 could not be set.
6. Prescaler and Swallow Counter
The dual modular prescaler (P/P+1) and the swallow counter are used to provide a large dividing ratio. The prescaler is set by
{PRE[1:0]}, which is a 2-bit address of D[15:14] in <Address3>.
{PRE[1:0]}=”00”: P=8, dividing ratio = 8/9
{PRE[1:0]}=”01”: P=16, dividing ratio = 16/17
{PRE[1:0]}=”10”: P=32, dividing ratio = 32/33
{PRE[1:0]}=”11”: Prohibited
7. Power Save Mode
AK1542A can be operated in the power-down or power-save mode as necessary by using the external control pins [PDN1]
and [PDN2].
Power On
See “13. Power-up Sequence”. It is necessary to bring [PDN1] to “High” first, then [PDN2]. Bringing [PDN1] and [PDN2]
to “High” simultaneously is prohibited.
Normal Operation
Pin name
State
PDN1
PDN2
“Low”
“Low”
Power down
“Low”
“High”
Prohibited
“High”
“Low”
Power save Mode
“High”
“High”
Normal Operation
Note 1) and Note 2)
Note 1)
Register setup can be made 50µs after [PDN1] is set to “High”. The charge pump is in the Hi-Z state.
Note 2)
Register settings are maintained when [PDN2] is set to “Low” during normal operation.
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9. Register Map
Name
Data
Address
A/B
0
0
0
1
CP
0
0
1
0
0
0
1
1
Function
0
1
0
0
GPO
0
1
0
1
D19 to D0
Ref/Pres
A/B
D19
D18
D17
0
B
[12]
B
[11]
D16 D15 D14 D13 D12 D11 D10 D9
B
[10]
B
[9]
B
[8]
B
[7]
B
[6]
B
[5]
D8
D7
D6
D5
D4
D3
D2
D1
D0
Address
B
[4]
B
[3]
B
[2]
B
[1]
B
[0]
A
[5]
A
[4]
A
[3]
A
[2]
A
[1]
A
[0]
0x01
CP2
[2]
CP2
[1]
CP2
[0]
0
0
CP1
[3]
CP1
[2]
CP1
[1]
CP1
[0]
0x02
R
[8]
R
[7]
R
[6]
R
[5]
R
[4]
R
[3]
R
[2]
R
[1]
R
[0]
0x03
CP
0
0
0
0
0
0
0
0
0
0
CP2
[3]
Ref/Pres
0
0
0
0
PRE
[1]
PRE
[0]
R
[13]
R
[12]
R
[11]
R
[10]
R
[9]
Function
0
LDCNT
SEL[1]
LDCNT
SEL[0]
FAST
EN
CP
HiZ
CP
POLA
LD
GPO
0
0
0
0
0
0
0
FAST FAST FAST FAST FAST FAST FAST FAST FAST FAST FAST FAST FAST
[12]
[11]
[10]
[9]
[8]
[7]
[6]
[5]
[4]
[3]
[2]
[1]
[0]
0
0
0
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0
0
0
0
0
0
0
0
GPO
2
GPO
1
0x04
0x05
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[AK1542A]
Notes for writing into registers
(1) The data at addresses 0x02 and 0x03 are committed to all related circuits when address 0x01 is written, which means
that the data of these 3 addresses (0x01, 0x02 and 0x03) are committed to all related circuits at the same time.
(2)
Addresses 0x04 and 0x05 could be written individually from other addresses.
(3)
The initial register values are not defined. Therefore, even after [PDN1] is turned ON, each bit value remains undefined.
In order to set all register values, it is required to write the data in all addresses of the register.
○
Examples of writing into registers
(Ex. 1) Power-On ⇒Writing these three-word data is required.
(1)
Write a charge pump current value to address 0x02.
The data at address 0x02 is not committed to all related circuits at this time. Instead, it is stored in the on-chip buffer.
(2)
Write a division number for the prescaler and a reference counter value to address 0x03.
The data at the address 0x03 is not committed to all related circuits at this time. Instead, it is stored in the on-chip buffer.
(3)
Write values for A counter and B counter at the address 0x01.
The data of these 3 addresses (0x01, 0x02 and 0x03) are committed to all related circuits at this time.
(Ex. 2) Changing frequency settings
(1) Write values for A counter and B counter at the address 0x01.
The data of these 3 addresses (0x01, 0x02 and 0x03) are committed to all related circuits at a time. The last data written
into addresses 0x02 and 0x03 are committed.
(Ex. 3) Changing charge pump current ⇒Writing these two-word data is required.
(1) Write a charge pump current value at the address 0x02.
The data in address 0x02 is not committed to all related circuits at this time. Instead, it is stored in the on-chip buffer.
(2)
Write values for A counter and B counter at the address 0x01.
The data of these 3 addresses (0x01, 0x02 and 0x03) are committed to all related circuits at a time. The last data written
into address 0x03 is committed.
(Ex. 4) Changing reference dividing number ⇒Writing these two-word data is required.
(1) Write a division number for the prescaler and a reference counter value at the address 0x03.
The data at the address 0x03 is not committed to all related circuits at this time. Instead, it is stored in the on-chip buffer.
(2) Write values for A counter and B counter at the address 0x01.
The data of these 3 addresses (0x01, 0x02 and 0x03) are committed to all related circuits at a time. The last data written
into address 0x03 is committed.
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[AK1542A]
10. Register Function Description
< Address1 : A/B >
D19
D[18:6]
D[5:0]
Address
0
B[12:0]
A[5:0]
0001
B[12:0]: B (Programmable) counters value
D18
D17
D16
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
Function
Remarks
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Prohibited
0
0
0
0
0
0
0
0
0
0
0
0
1
1 Dec
Prohibited
0
0
0
0
0
0
0
0
0
0
0
1
0
2 Dec
Prohibited
0
0
0
0
0
0
0
0
0
0
0
1
1
3 Dec
DATA
1
1
1
1
1
1
1
1
1
1
1
0
1
8189 Dec
1
1
1
1
1
1
1
1
1
1
1
1
0
8190 Dec
1
1
1
1
1
1
1
1
1
1
1
1
1
8191 Dec
A[5:0]: A (Swallow) counter value
D5
D4
D3
D2
D1
D0
Function
0
0
0
0
0
0
0
0
0
0
0
0
1
1 Dec
0
0
0
0
1
0
2 Dec
0
0
0
0
1
1
3 Dec
Remarks
DATA
1
1
1
1
0
1
61 Dec
1
1
1
1
1
0
62 Dec
1
1
1
1
1
1
63 Dec
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[AK1542A]
* Requirements for A[5:0] and B[12:0]
The data at A[5:0] and B[12:0] must meet the following requirements:
B[12:0] ≥ 3, B[12:0] ≥ A[5:0]
See “1. Frequency Setup” on Page 11 for details of the relationship between a frequency division
number and the data at A[5:0] and B[12:0].
< Address2 : CP >
D19
D18
D17
D16
D15
D14
D13
D12
D[11:10]
D[9:6]
D[5:4]
D[3:0]
Address
0
0
0
0
0
0
0
0
0
CP2[3:0]
0
CP1[3:0]
0010
CP1[3:0] : Charge pump current for normal operation
CP2[3:0] : Charge pump current for Fast Lock Up mode
In AK1542A, two types of charge pump current CP1 and CP2 could be set.
CP1 is the charge pump current setting for normal operation.
CP2 is the charge pump current setting for Fast Lock Up mode.
The following formula shows the relationship between the resistance value, the register setting and the
electric current value.
Setting 0~7;
Charge pump minimum current (Icp_min) [A] = 8.55 / Resistance connected to the [BIAS] pin (Ω)
Charge pump current [A] = Icp_min [A] × (CP1 or CP2 + 1)
Setting 8;
Charge pump current [A] = Icp_min [A] × 0.5
CP1[3:0]
Charge pump currents [µA]
CP2[3:0]
22kΩ
27kΩ
33kΩ
000
388
316
259
001
776
632
518
010
1164
948
777
011
1552
1264
1036
100
1940
1580
1295
101
2328
1896
1554
110
2716
2212
1813
111
3104
2528
2072
1XXX
194
158
129
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[AK1542A]
< Address3 : Ref/Pres >
D19
D18
D17
D16
D[15:14]
D[13:0]
Address
0
0
0
0
PRE[1:0]
R[13:0]
0011
PRE[1:0] : Prescaler division ratio (8/9, 16/17, 32/33)
The following settings can be chosen for the prescaler division.
D15
D14
Function
0
0
8/9 (P=8)
0
1
16/17 (P=16)
1
0
32/33 (P=32)
1
1
Prohibited
Remarks
R[13:0]: Reference clock division number
The following settings can be chosen for the reference clock division.
The allowed range is 4 (1/4 division) to 16383 (1/16383 division).
0 to 3 cannot be set.
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
Function
Remarks
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Prohibited
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1/1 division
Prohibited
0
0
0
0
0
0
0
0
0
0
0
0
1
0
1/2 division
Prohibited
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1/3 division
Prohibited
0
0
0
0
0
0
0
0
0
0
0
1
0
0
1/4 division
1/16381
division
1/16382
division
1/16383
division
DATA
1
1
1
1
1
1
1
1
1
1
1
1
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
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[AK1542A]
< Address4 : Function >
D19
D18
D17
D16
D15
D14
D13
D[12:0]
Address
0
LDCNT
SEL[1]
LDCNT
SEL[0]
FAST
EN
CP
HiZ
CP
POLA
LD
FAST[12:0]
0100
LDCNTSEL[1:0] : Counter value for lock detect
The counter value for digital lock detect can be set.
D18
D17
Function
0
0
Counter value = 7
0
1
Counter value = 15
1
0
Counter value = 31
1
1
Counter value = 63
Remarks
FASTEN : The Fast Lock Up mode enable/disable setting
The Fast Lock Up mode can be enabled or disabled.
D16
Function
Remarks
0
The data in CP2[3:0] and FAST[12:0] are disabled.
1
The data in CP2[3:0] and FAST[12:0] are enabled.
CPHIZ: TRI-STATE output setting for charge pumps 1 and 2
D15
Function
Remarks
0
Charge pump is activated.
Use this setting for normal
operation.
1
TRI-STATE
Note 1)
Note 1) The charge pump output is turned OFF and put in the Hi-Z state.
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[AK1542A]
CPPOLA: Selects positive or negative output polarity for CP1 and CP2.
D14
Function
0
Positive
1
Negative
Remarks
High
VCO frequency
Positive
Negative
Low
Low
Charge pump output voltage
High
Fig. 11 Charge Pump Output Polarity
LD: Selects analog or digital for Lock Detect.
D13
Function
0
Digital lock detect mode
1
Analog lock detect mode
Remarks
For detailed functional descriptions, see the section “Lock Detect (LD) Signal” in “8. Block Functional
Description”.
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[AK1542A]
FAST[12:0] : FAST counter value
A decimal number from 1 to 8191 can be set. This value determines the time period during which the
CP2 is ON for the Fast Lock Up mode.
After the time period calculated by [phase detector frequency cycle × {FAST[12:0]} setting], the CP2 is
turned OFF.
0 could not be set.
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
Function
Remarks
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Prohibited
0
0
0
0
0
0
0
0
0
0
0
0
1
1 Dec
0
0
0
0
0
0
0
0
0
0
0
1
0
2 Dec
DATA
1
1
1
1
1
1
1
1
1
1
1
0
1
8189 Dec
1
1
1
1
1
1
1
1
1
1
1
1
0
8190 Dec
1
1
1
1
1
1
1
1
1
1
1
1
1
8191 Dec
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[AK1542A]
< Address5 : GPO >
D19
D18
D17
D16
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
Address
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
GPO2
GPO1
0101
GPO2: The state of the GPO2 pin
This value controls the General-Purpose output pin GPO2.
The voltage applied to the PVDD pin determines the “High” level output.
D1
Function
Remarks
0
“Low” output from the GPO2 pin
1
“High” output from the GPO2 pin
GPO1: The state of the GPO1 pin
This value controls the General-Purpose output pin GPO1.
The voltage applied to the PVDD pin determines the “High” level output.
D0
Function
Remarks
0
“Low” output from the GPO1 pin
1
“High” output from the GPO1 pin
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[AK1542A]
11. IC Interface Schematic
No.
Name
I/O
R0(Ω)
4
LE
I
300
5
DATA
I
300
6
CLK
I
300
8
PDN2
I
300
9
PDN1
I
300
2
TEST3
I
300
3
TEST1
I
300
11
TEST2
I
300
Cur(µA)
Function
Digital input pins
R0
Digital input pins Pull-Down
R0
100k
7
LD
O
12
GPO1
O
13
GPO2
O
10
REFIN
I
Digital output pin
300
Analog input pin
R0
15
VREF
IO
300
19
BIAS
IO
300
22
CPZ
IO
300
Analog I/O pin
R0
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[AK1542A]
No.
Name
I/O
23
SWIN
I
Analog input pin
21
CP
O
Analog output pin
16
RFINN
I
12k
20
17
RFINP
I
12k
20
R0(Ω)
Cur(µA)
Function
Analog input pin(RF signal input)
R0
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[AK1542A]
12. Recommended Schematic for Off-Chip Component
1. PVDD, CPVDD
LSI
PVDD
0.01F
100pF
10F
CPVDD
0.01F
100pF
10F
2. VREF
LSI
VREF
220nF±10%
VREF2
3. TEST [1,2,3]
LSI
TEST1,2,3
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[AK1542A]
4. REFIN
LSI
REFIN
100pF±10%
5. RFINP, RFINN
LSI
VCO Output
RFINP
51Ω
100pF±10%
RFINN
100pF±10%
6. BIAS
LSI
BIAS
22kΩ~33kΩ
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[AK1542A]
13. Power-up Sequence
1. Power-up Sequence (Recommended)
PVDD,CPVDD
T> 0
PDN1
50s
On-chip LDO
1.8V
0V
(1.8V)
Refin
Don’t care
Registers can be written
input
Internal resiter values are set
Write the data in all
Write to the register
addresses of the register
PDN2(PLL)
HiZ
CP
Output
Fig. 12 Recommended Power Sequence
Note 1)
The initial register values are not defined. Therefore, even after [PDN1] is set to “High”, each bit value remains
undefined. In order to set all register values, it is required to write the data in all addresses of the register.
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[AK1542A]
2. Power-up Sequence
PVDD,CPVDD
PDN1
50s
1.8V
On-chip LDO
0V
(1.8V)
Refin must be input before setting [PDN2] to “High”
Refin
Write to register
Don’t care
input
H or L
Registers can be written
After more than 50s from the [PDN1] is set to “High”
Here [PDN1] is set to “High” after or at the same time as power-up.
PDN2(PLL)
HiZ
CP
Output(*1)
*1
CP output is not defined before writing the data in
all addresses of the register. After writing them,
CP output can be controlled by register.
Fig. 13 Power Sequence
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[AK1542A]
14. Typical Evaluation Board Schematic
RFOUT
AK1542A
Loop Filter
100pF
REFIN
CP
18
100pF
R3
VCO
C1
R2'
R2
C3
18
18
VREF
220nF
SWIN
C2
CPZ
BIAS
27k
RFINP
100pF
51
RFINN
100pF
Fig. 14 Typical Evaluation Board Schematic
Note 1)
The [CPZ] pin should be connected to the R2 and C2, which are intermediate nodes, even if the Fast Lock Up is
not used. Therefore, R2 must be connected to the [CP] pin, while C2 must be connected to the ground.
Note 2)
In Fast Lock Up mode, R2 and R2’ are connected in parallel by internal switching. For calculation of loop band
width and phase margin at Fast Lock Up mode, the resistance should be considered as parallel of R2 and R2’.
Note 3)
It is recommended that the exposed pad at the center of the backside should be connected to the ground.
Note 4)
Test pins (TEST1 to 3) should be connected to the ground.
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[AK1542A]
CPVSS
CPVDD
PVDD
PVSS
VREF
DVSS
15. Block Diagram by Power Supply
LDO
BIAS
R COUNTER
14 bit
REFIN
CP
CHARGE
PUMP
PHASE
FREQENCY
DETECTOR
CLK
CPZ
REGISTER
24 bit
DATA
LE
FAST
COUNTER
LOCK DETECT
SWALLOW
COUNTER
6 bit
PROGRAMABLE
COUNTER
13 bit
SWIN
N DIVIDER
CPVDD
GPO2
PVDD
GPO1
8/9, 16/17, 32/33
PDN2
-
PDN1
RFINN
LD
TEST3
PRESCALER
TEST2
+
TEST1
RFINP
Fig. 15 Power Supply Block Diagram
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[AK1542A]
16. Outer Dimensions
4.00±0.07
2.40
18
12
19
7
24
B
1
6
C0.30
2.00
0.05 M S
A B
0.22±0.05
0.75MAX
0.12~0.18
0.17~0.27
0.00~0.05
0.05 S
0.70
0.5
0.05MAX
S
Part A
0.40±0.07
2.40
A
2.00
4.00±0.07
13
Detailed chart in part A
Fig. 16 Package Outer Dimensions
Note)
It is recommended to connect the exposed pad at the center of the backside to the ground, although it will not make
any impact on the electrical characteristics if it is open.
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[AK1542A]
17. Marking
(a) Style
:
QFN
(b) Number of pins
:
24
(c) 1 pin marking:
:
○
(d) Product number
:
1542A
(e) Date code
:
YWWL (4 digits)
Y
:
Lower 1 digit of calendar year (Year 2012 → 2, 2013 → 3 ...)
WW
:
Week
L
:
Lot identification, given to each product lot which is made in a week
 LOT ID is given in alphabetical order (A, B, C…).
1542A
YWWL
(d)
(e)
(c)
Fig. 17 Marking
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[AK1542A]
IMPORTANT NOTICE
 Descriptions of external circuits, application circuits, software and other related information contained in this
document are provided only to illustrate the operation and application examples of the semiconductor
products. You are fully responsible for the incorporation of these external circuits, application circuits,
software and other related information in the design of your equipment. Asahi Kasei Microdevices
Corporation (AKM) assumes no responsibility for any losses incurred by you or third parties arising from the
use of these information herein. AKM assumes no liability for infringement of any patent, intellectual
property, or other rights in the application or use of such information contained herein.
 Any export of these products, or devices or systems containing them, may require an export license or
other official approval under the law and regulations of the country of export pertaining to customs and
tariffs, currency exchange, or strategic materials.
 AKM products are neither intended nor authorized for use as critical componentsNote1) in any safety, life
support, or other hazard related device or system Note2), and AKM assumes no responsibility for such use,
except for the use approved with the express written consent by Representative Director of AKM. As used
here:
Note1) A critical component is one whose failure to function or perform may reasonably be expected to
result, whether directly or indirectly, in the loss of the safety or effectiveness of the device or system
containing it, and which must therefore meet very high standards of performance and reliability.
Note2) A hazard related device or system is one designed or intended for life support or maintenance of
safety or for applications in medicine, aerospace, nuclear energy, or other fields, in which its failure to
function or perform may reasonably be expected to result in loss of life or in significant injury or damage
to person or property.
 It is the responsibility of the buyer or distributor of AKM products, who distributes, disposes of, or otherwise
places the product with a third party, to notify such third party in advance of the above content and
conditions, and the buyer or distributor agrees to assume any and all responsibility and liability for and hold
AKM harmless from any and all claims arising from the use of said product in the absence of such
notification.
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