NSC LMX2315WG-MLS, LMX2315TM Datasheet

TL/W/12339
LMX2315/LMX2320/LMX2325 PLLatinum Frequency
Synthesizer for RF Personal Communications
LMX2325 2.5 GHz LMX2320 2.0 GHz LMX2315 1.2 GHz
September 1996
LMX2315/LMX2320/LMX2325 PLLatinum
TM
Frequency Synthesizer for RF Personal Communications LMX2325 2.5 GHz LMX2320 2.0 GHz LMX2315 1.2 GHz
General Description
The LMX2315/2320/2325’s are high performance frequen­cy synthesizers with integrated prescalers designed for RF operation up to 2.5 GHz. They are fabricated using Nation­al’s ABiC IV BiCMOS process.
A 64/65 or a 128/129 divide ratio can be selected for the LMX2315 and LMX2320 RF synthesizer at input frequencies of up to 1.2 GHz and 2.0 GHz, while 32/33 and 64/65 divide ratios are available in the 2.5 GHz LMX2325. Using a propri­etary digital phase locked loop technique, the LMX2315/ 2320/2325’s linear phase detector characteristics can gen­erate very stable, low noise signals for controlling a local oscillator.
Serial data is transferred into the LMX2320 and the LMX2325 via a three line MICROWIRE
TM
interface (Data, Enable, Clock). Supply voltage can range from 2.7V to 5.5V. The LMX2315, LMX2320 and the LMX2325 feature very low current consumption, typically 6 mA, 10 mA and 11 mA re­spectively.
The LMX2315, LMX2320 and the LMX2325 are available in a TSSOP 20-pin surface mount plastic package.
Features
Y
RF operation up to 2.5 GHz
Y
2.7V to 5.5V operation
Y
Low current consumption
Y
Dual modulus prescaler: LMX2325 32/33 or 64/65 LMX2320/LMX2315 64/65 or 128/129
Y
Internal balanced, low leakage charge pump
Y
Power down feature for sleep mode: I
CC
e
30 mA (typ) at V
CC
e
3V
Y
Small-outline, plastic, surface mount TSSOP, 0.173
×
wide
Applications
Y
Cellular telephone systems (GSM, IS-54, IS-95, (RCR-27)
Y
Portable wireless communications (DECT, PHS)
Y
CATV
Y
Other wireless communication systems
Block Diagram
TL/W/12339– 1
TRI-STATEÉis a registered trademark of National Semiconductor Corporation. MICROWIRE
TM
and PLLatinumTMare trademarks of National Semiconductor Corporation.
C
1996 National Semiconductor Corporation RRD-B30M106/Printed in U. S. A.
http://www.national.com
Connection Diagrams
LMX2315/LMX2320/LMX2325
TL/W/12339– 2
20-Lead (0.173×Wide) Thin Shrink Small Outline Package (TM)
Order Number LMX2315TM, LMX2315TMX, LMX2325TM, LMX2325TMX, LMX2320TM or LMX2320TMX
See NS Package Number MTC20
Pin Descriptions
Pin No. Pin Name I/O Description
1 OSC
IN
I Oscillator input. A CMOS inverting gate input intended for connection to a crystal resonator for
operation as an oscillator. The input has a V
CC
/2 input threshold and can be driven from an external
CMOS or TTL logic gate. May also be used as a buffer for an externally provided reference oscillator.
3 OSC
OUT
O Oscillator output.
4V
P
Power supply for charge pump. Must betVCC.
5V
CC
Power supply voltage input. Input may range from 2.7V to 5.5V. Bypass capacitors should be placed as close as possible to this pin and be connected directly to the ground plane.
6DoO Internal charge pump output. For connection to a loop filter for driving the input of an external VCO.
7 GND Ground.
8 LD O Lock detect. Output provided to indicate when the VCO frequency is in ‘‘lock’’. When the loop is
locked, the pin’s output is HIGH with narrow low pulses.
10 f
IN
I Prescaler input. Small signal input from the VCO.
11 CLOCK I High impedance CMOS Clock input. Data is clocked in on the rising edge, into the various counters
and registers.
13 DATA I Binary serial data input. Data entered MSB first. LSB is control bit. High impedance CMOS input.
14 LE I Load enable input (with internal pull-up resistor). When LE transitions HIGH, data stored in the shift
registers is loaded into the appropriate latch (control bit dependent). Clock must be low when LE toggles high or low. See Serial Data Input Timing Diagram.
15 FC I Phase control select (with internal pull-up resistor). When FC is LOW, the polarity of the phase
comparator and charge pump combination is reversed.
16 BISW O Analog switch output. When LE is HIGH, the analog switch is ON, routing the internal charge pump
output through BISW (as well as through D
o
).
17 f
OUT
O Monitor pin of phase comparator input. CMOS output.
18 w
p
O Output for external charge pump. wpis an open drain N-channel transistor and requires a pull-up
resistor.
19 PWDN I Power Down (with internal pull-up resistor).
PWDN
e
HIGH for normal operation.
PWDN
e
LOW for power saving.
Power down function is gated by the return of the charge pump to a TRI-STATE
É
condition.
20 w
r
O Output for external charge pump. wris a CMOS logic output.
2,9,12 NC No connect.
http://www.national.com 2
Functional Block Diagram
TL/W/12339– 3
Note 1: The prescalar for the LMX2315 and LMX2320 is either 64/65 or 128/129, while the prescalar for the LMX2325 is 32/33 or 64/65.
Note 2: The power down function is gated by the charge pump to prevent unwanted frequency jumps. Once the power down pin is brought low the part will go into
power down mode when the charge pump reaches a TRI-STATE condition.
http://www.national.com3
Absolute Maximum Ratings (Notes 1, 2)
If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/Distributors for availability and specifications.
Power Supply Voltage
V
CC
b
0.3V toa6.5V
V
P
b
0.3V toa6.5V
Voltage on Any Pin
with GND
e
0V (VI)
b
0.3V toa6.5V
Storage Temperature Range (TS)
b
65§Ctoa150§C
Lead Temperature (TL) (solder, 4 sec.)
a
260§C
Recommended Operating Conditions
Power Supply Voltage
V
CC
2.7V to 5.5V
V
P
VCCtoa5.5V
Operating Temperature (TA)
b
40§Ctoa85§C
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but do not guarantee specific perform­ance limits. For guaranteed specifications and test conditions, see the Elec­trical Characteristics. The guaranteed specifications apply only for the test conditions listed.
Note 2: This device is a high performance RF integrated circuit with an ESD rating
k
2 kV and is ESD sensitive. Handling and assembly of this device
should be done at ESD workstations.
Electrical Characteristics
LMX2325 and LMX2320 V
CC
e
V
P
e
3.0V; LMX2315 V
CC
e
V
P
e
5.0V;b40§CkT
A
k
85§C, except as specified
Symbol Parameter Conditions Min Typ Max Units
I
CC
Power Supply Current LMX2315 V
CC
e
3.0V 6.0 8.0 mA
V
CC
e
5.0V 6.5 8.5 mA
LMX2320 V
CC
e
3.0V 10 13.5 mA
LMX2325 V
CC
e
3.0V 11 15 mA
I
CC-PWDN
Power Down Current V
CC
e
3.0V 30 180 mA
V
CC
e
5.0V 60 350 mA
f
IN
Maximum Operating Frequency LMX2315 1.2
LMX2320 2.0 GHz
LMX2325 2.5
f
OSC
Oscillator Frequency 5 20 MHz
No Load on OSC
out
5 40 MHz
f
w
Phase Detector Frequency 10 MHz
Pf
IN
Input Sensitivity V
CC
e
2.7V to 3.3V
b
15
a
6
dBm
V
CC
e
3.3V to 5.5V
b
10
a
6
V
OSC
Oscillator Sensitivity OSC
IN
0.5 V
PP
V
IH
High-Level Input Voltage * 0.7 V
CC
V
V
IL
Low-Level Input Voltage * 0.3 V
CC
V
I
IH
High-Level Input Current (Clock, Data) V
IH
e
V
CC
e
5.5V
b
1.0 1.0 mA
I
IL
Low-Level Input Current (Clock, Data) V
IL
e
0V, V
CC
e
5.5V
b
1.0 1.0 mA
I
IH
Oscillator Input Current V
IH
e
V
CC
e
5.5V 100 mA
I
IL
V
IL
e
0V, V
CC
e
5.5V
b
100 mA
I
IH
High-Level Input Current (LE, FC) V
IH
e
V
CC
e
5.5V
b
1.0 1.0 mA
I
IL
Low-Level Input Current (LE, FC) V
IL
e
0V, V
CC
e
5.5V
b
100 1.0 mA
*Except fINand OSC
IN
http://www.national.com 4
Electrical CharacteristicsLMX2325 and LMX2320 V
CC
e
V
P
e
3.0V; LMX2315 V
CC
e
V
P
e
5.0V;b40§C
k
T
A
k
85§C, except as specified (Continued)
Symbol Parameter Conditions Min Typ Max Units
I
Do-source
Charge Pump Output Current V
CC
e
V
P
e
3.0V, V
D
o
e
VP/2
b
2.5 mA
I
Do-sink
V
CC
e
V
P
e
3.0V, V
D
o
e
VP/2 2.5 mA
I
Do-source
Charge Pump Output Current V
CC
e
V
P
e
5.0V, V
D
o
e
VP/2
b
5.0 mA
I
Do-sink
V
CC
e
V
P
e
5.0V, V
D
o
e
VP/2 5.0 mA
I
Do-Tri
Charge Pump TRI-STATEÉCurrent 0.5VsV
D
o
s
V
P
b
0.5V
b
2.5 2.5 nA
T
e
85§C
I
D
o
vs V
D
o
Charge Pump Output Current 0.5VsV
D
o
s
V
P
b
0.5V
Magnitude Variation vs Voltage T
e
25§C15%
(Note 1)
I
Do-sink
vs Charge Pump Output Current V
D
o
e
VP/2
I
Do-source
Sink vs Source Mismatch Te25§C10% (Note 2)
I
D
o
vs T Charge Pump Output Current
b
40§CkTk85§C
Magnitude Variation vs Temperature V
D
o
e
VP/2 10 %
(Note 3)
V
OH
High-Level Output Voltage I
OH
eb
1.0 mA** V
CC
b
0.8 V
V
OL
Low-Level Output Voltage I
OL
e
1.0 mA** 0.4 V
V
OH
High-Level Output Voltage (OSC
OUT
)I
OH
eb
200 mAV
CC
b
0.8 V
V
OL
Low-Level Output Voltage (OSC
OUT
)I
OL
e
200 mA 0.4 V
I
OL
Open Drain Output Current (wp)V
CC
e
5.0V, V
OL
e
0.4V 1.0 mA
I
OH
Open Drain Output Current (wp)V
OH
e
5.5V 100 mA
R
ON
Analog Switch ON Resistance (2315) 100 X
t
CS
Data to Clock Set Up Time See Data Input Timing 50 ns
t
CH
Data to Clock Hold Time See Data Input Timing 10 ns
t
CWH
Clock Pulse Width High See Data Input Timing 50 ns
t
CWL
Clock Pulse Width Low See Data Input Timing 50 ns
t
ES
Clock to Enable Set Up Time See Data Input Timing 50 ns
t
EW
Enable Pulse Width See Data Input Timing 50 ns
**Except OSC
OUT
Notes 1, 2, 3: See related equations in Charge Pump Current Specification Definitions
http://www.national.com5
Typical Performance Characteristics
ICCvs VCCLMX2320/25
TL/W/12339– 4
ICCvs VCCLMX2315
TL/W/12339– 51
Charge Pump Current vs DoVoltage
TL/W/12339– 40
Charge Pump Current vs DoVoltage
TL/W/12339– 7
Charge Pump Current Variation
TL/W/12339– 8
Sink vs Source Mismatch vs DoVoltage
TL/W/12339– 9
http://www.national.com 6
Typical Performance Characteristics (Continued)
I
D
o
TRI-STATE vs DoVoltage
TL/W/12339– 5
Oscillator Input Sensitivity
TL/W/12339– 14
LMX2320/25 Input Sensitivity vs Frequency
TL/W/12339– 10
LMX2320/25 Input Sensitivity vs Frequency
TL/W/12339– 11
LMX2315 Input Sensitivity vs Frequency
TL/W/12339– 41
LMX2315 Input Sensitivity vs Frequency
TL/W/12339– 42
http://www.national.com7
Loading...
+ 15 hidden pages