Dual Low Power PLL
Frequency Synthesizer
ADF4212L
FEATURES
GENERAL DESCRIPTION
IDD total: 7.5 mA
Bandwidth RF/IF: 2.4 GHz/1.0 GHz
2.7 V to 3.3 V power supply
Separate VP allows extended tuning voltage
Programmable dual modulus prescaler
RF and IF: 8/9, 16/17, 32/33, 64/65
Programmable charge pump currents
3-wire serial interface
The ADF4212L is a dual frequency synthesizer that can be used
to implement local oscillators (LO) in the up-conversion and
down-conversion sections of wireless receivers and transmitters.
It can provide the LO for both the RF and IF sections. It consists
of a low noise digital phase frequency detector (PFD), a precision
charge pump, a programmable reference divider, programmable
A and B counters, and a dual modulus prescaler (P/P + 1). The
A (6-bit) and B (12-bit) counters, in conjunction with the dual
modulus prescaler (P/P + 1), implement an N divider (N = BP +
A). In addition, the 15-bit reference counter (R counter) allows
selectable REFIN frequencies at the PFD input. A complete phase-
locked loop (PLL) can be implemented if the synthesizer is used
with external loop filters and voltage controlled oscillators (VCOs).
Analog and digital lock detect
Fastlock mode
Power-down mode
20-lead TSSOP and 20-lead LFCSP packages
APPLICATIONS
Control of all the on-chip registers is via a simple 3-wire
interface with 1.8 V compatibility. The devices operate with a
power supply ranging from 2.7 V to 3.3 V and can be powered
down when not in use.
Wireless handsets (GSM, PCS, DCS, DSC1800, CDMA,
WCDMA)
Base stations for wireless Radio (GSM, PCS, DCS,
CDMA, WCDMA)
Wireless LANS
Cable TV tuners (CATV)
Communications test equipment
FUNCTIONAL BLOCK DIAGRAM
V
1
V
2
V
1
V
2
R
SET
DD
DD
P
P
ADF4212L
IF PHASE
FREQUENCY
DETECTOR
REFERENCE
12-BIT IF
B-COUNTER
CHARGE
PUMP
CP
IF
IF
IN
IF
PRESCALER
6-BIT IF
A-COUNTER
IF CURRENT
SETTING
IF
LOCK
DETECT
IFCP3 IFCP2 IFCP1
REF
OSCILLATOR
IN
15-BIT IF
R-COUNTER
OUTPUT
MUX
MUXOUT
CLK
22-BIT
DATA
REGISTER
DATA
LE
SDOUT
RFCP3 RFCP2 RFCP1
REFERENCE
RF
15-BIT RF
R-COUNTER
LOCK
DETECT
CHARGE
PUMP
12-BIT RF
B-COUNTER
CP
RF
RF
IN
RF
RF PHASE
FREQUENCY
DETECTOR
PRESCALER
REFERENCE
6-BIT RF
A-COUNTER
R
SET
FL SWITCH
O
FL
O
DGND
RF
AGND
DGND
AGND
RF
IF
IF
Figure 1.
Rev. B
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