LMX2335L/LMX2336L
PLLatinum
TM
Low Power Dual Frequency Synthesizer for
RF Personal Communications
LMX2335L
1.1 GHz/1.1 GHz
LMX2336L
2.0 GHz/1.1 GHz
General Description
The LMX2335L and LMX2336L are monolithic, integrated
dual frequency synthesizers, including two high frequency
prescalers, and are designed for applications requiring two
RF phase-lock loops. They are fabricated using National's
0.5 ABiC V silicon BiCMOS process.
The LMX2335L/36L contains two dual modulus prescalers. A
64/65 or a 128/129 prescaler can be selected for each RF
synthesizer. A second reference divider chain is included in
the IC for improved system noise. The LMX2335L/36L com-
bined with a high quality reference oscillator, two loop filters,
and two external voltage controlled oscillators generates
very stable low noise RF local oscillator signals.
Serial data is transferred into the LMX2335L/36L via a three
wire interface (Data, Enable, Clock). Supply voltage can
range from 2.7V to 5.5V. The LMX2335L/36L feature very
low current consumption; LMX2335L 4.0 mA at 5V,
LMX2336L 5.5 mA at 5V. The LMX2335L is available in SO,
TSSOP and CSP 16-pin surface mount plastic packages.
The LMX2336L is available in a TSSOP 20-pin and CSP
24-pin surface mount plastic package.
Features
n
Ultra low current consumption
n
2.7V to 5.5V operation
n
Selectable synchronous and asynchronous powerdown
mode:
I
CC
= 1 A (typ)
n
Dual modulus prescaler: 64/65 or 128/129
n
Selectable charge pump TRI-STATE
mode
n
Selectable charge pump current levels
n
Selectable Fastlock
TM
mode
n
Upgrade and compatible to LMX2335/36
n
Small-outline, plastic, surface mount TSSOP package
n
LMX2336 available in CSP package
Applications
n
Cellular telephone systems (AMPS, ETACS, RCR-27)
n
Cordless telephone systems
(DECT, ISM , PHS, CT-1+)
n
Personal Communication Systems
(DCS-1800, PCN-1900)
n
Dual Mode PCS phones
n
Cable TV Tuners (CATV)
n
Other wireless communication systems
Functional Block Diagram
TRI-STATE
is a registered trademark of National Semiconductor Corporation.
Fastlock
TM
, MICROWIRE
TM
and PLLatinum
TM
are trademarks of National Semiconductor Corporation.
DS012807-1
PRELIMINARY
June 1999
LMX2335L/LMX2336L
PLLatinum
Low
Power
Dual
Frequency
Synthesizer
for
RF
Personal
Communications
1999 National Semiconductor Corporation
DS012807
www.national.com
Connection Diagrams
Pin Descriptions
Pin No.
Pin No.
Pin No.
Pin No.
Pin
I/O
Description
2336LTM
2336LSLB 2335LTM
2335LSLB
Name
1
24
1
16
V
CC
1
Power supply voltage input for RF1 analog and RF1 digital
circuits. Input may range from 2.7V to 5.5V. V
CC
1 must equal
V
CC
2. Bypass capacitors should be placed as close as possible
to this pin and be connected directly to the ground plane.
2
2
2
1
V
p
1
Power supply for RF1 charge pump. Must be
V
CC
.
3
3
3
2
D
o
1
O
RF1 charge pump output. For connection to a loop filter for
driving the input of an external VCO.
4
4
4
3
GND
LMX2335L: Ground for RF1 analog and RF1 digital circuits.
LMX2336L: Ground for RF digital circuits.
5
5
5
4
f
IN
1
I
RF1 prescaler input. Small signal input from the VCO.
6
6
X
X
/f
IN
1
I
RF1 prescaler complementary input. A bypass capacitor should
be placed as close as possible to this pin and be connected
directly to the ground plane. Capacitor is optional with loss of
some sensitivity.
7
7
X
X
GND
Ground for RF1 analog circuitry.
LMX2335L
(Top View)
DS012807-2
Order Number LMX2335LM or LM2335LTM
NS Package Number M16A and MTC16
LMX2335L
(Top View)
DS012807-38
Order Number LMX2335LSLB
NS Package Number SLB16A
LMX2336L
(Top View)
DS012807-3
Order Number LMX2336LTM
NS Package Number MTC20
LMX2336L
(Top View)
DS012807-36
Order Number LMX2336LSLB
NS Package Number SLB24A
www.national.com
2
Pin Descriptions
(Continued)
Pin No.
Pin No.
Pin No.
Pin No.
Pin
I/O
Description
2336LTM
2336LSLB 2335LTM
2335LSLB
Name
8
8
6
5
OSC
in
I
Oscillator input. The input has a V
CC
/2 input threshold and can
be driven from an external CMOS or TTL logic gate.
9
10
7
6
OSC
out
O
Oscillator output.
10
11
8
7
F
o
LD
O
Multiplexed output of the programmable or reference dividers,
lock detect signals and Fastlock mode. CMOS output
(see
Programmable Modes).
11
12
9
8
Clock
I
High impedance CMOS Clock input. Data for the various latches
is clocked in on the rising edge, into the 20-bit shift register.
12
14
10
9
Data
I
Binary serial data input. Data entered MSB first. The last two bits
are the control bits. High impedance CMOS input.
13
15
11
10
LE
I
Load enable high impedance CMOS input. When LE goes HIGH,
data stored in the shift registers is loaded into one of the 4
appropriate latches (control bit dependent).
14
16
X
X
GND
Ground for RF2 analog circuitry.
15
17
X
X
/f
IN
2
I
RF2 prescaler complementary input. A bypass capacitor should
be placed as close as possible to this pin and be connected
directly to the ground plane. Capacitor is optional with loss of
some sensitivity.
16
18
12
11
f
IN
2
I
RF2 prescaler input. Small signal input from the VCO.
17
19
13
12
GND
LMX2335L: Ground for RF2 analog, RF2 digital, MICROWIRE,
F
o
LD and Oscillator circuits. LMX2336L: Ground for IF digital,
MICROWIRE, F
o
LD and oscillator circuits.
18
20
14
13
D
o
2
O
RF2 charge pump output. For connection to a loop filter for
driving the input of an external VCO.
19
22
15
14
V
p
2
Power supply for RF2 charge pump. Must be
V
CC
.
20
23
16
15
V
CC
2
Power supply voltage input for RF2 analog, RF2 digital,
MICROWIRE, F
o
LD and oscillator circuits. Input may range from
2.7V to 5.5V. V
CC
2 must equal V
CC
1. Bypass capacitors should
be placed as close as possible to this pin and be connected
directly to the ground plane.
X
1, 9, 13,
21
X
X
NC
No connect.
www.national.com
3
Block Diagram
DS012807-4
Note 1: V
CC
1 supplies power to the RF1 prescaler, N-counter, R-counter, and phase detector. V
CC
2 supplies power to the RF2 prescaler, N-counter, phase
detector, R-counter along with the OSC
in
buffer, MICROWIRE, and F
o
LD. V
CC
1 and V
CC
2 are clamped to each other by diodes and must be run at the same
voltage level.
Note 2: V
P
1 and V
P
2 can be run separately as long as V
P
V
CC
.
LMX2335L Pin #
8/10
LMX2336L Pin #
Pin Name
F
o
LD
X signifies a function not bonded out to a pin
www.national.com
4
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
-0.3V to +6.5V
V
P
-0.3V to +6.5V
Voltage on Any Pin
with GND = 0V (V
I
)
-0.3V to V
CC
+0.3V
Storage Temperature Range (T
S
)
-65C to +150C
Lead Temperature (solder 4 sec.) (T
L
)
+260C
Recommended Operating
Conditions
Power Supply Voltage
V
CC
2.7V to 5.5V
V
P
V
CC
to +5.5V
Operating Temperature (T
A
)
-40C to +85C
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to
the device may occur. Recommended Operating Conditions indicate condi-
tions for which the device is intended to be functional, but do not guarantee
specific performance limits. For guaranteed specifications and test condi-
tions, 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
<
2 keV and is ESD sensitive. Handling and assembly of this device
should only be done at ESD protected work stations.
Electrical Characteristics
V
CC
= 5.0V, V
P
= 5.0V; T
A
= 25C, except as specified
Symbol
Parameter
Conditions
Value
Units
Min
Typ
Max
I
CC
Power Supply
LMX2335L
V
CC
= 2.7V to 5.5V
4.0
5.2
mA
Current
RF1 and RF2
I
CC
LMX2335L RF1 only
2.0
2.6
mA
I
CC
LMX2336L
5.5
7
mA
RF1 and RF2
LMX2336L RF1 only
3.3
4.3
mA
f
IN
1
Operating
Frequency
LMX2335L
0.100
1.1
GHz
f
IN
2
0.050
1.1
GHz
f
IN
1
LMX2336L
0.200
2.0
GHz
f
IN
2
0.050
1.1
GHz
I
CC-PWDN
Powerdown Current
LMX2335L/2336L
V
CC
= 5.5V
1
10
A
f
OSC
Oscillator Frequency
With resonator load on OSC
out
5
20
MHz
f
OSC
No load on OSC
out
5
40
MHz
f
Maximum Phase Detector Frequency
10
MHz
Pf
IN
RF Input Sensitivity
V
CC
= 3.0V, f
>
100 MHz
-15
0
dBm
Pf
IN
V
CC
= 5.0V, f
>
100 MHz
-10
0
V
OSC
Oscillator Sensitivity
OSC
in
0.5
V
PP
V
IH
High-Level Input Voltage
(Note 4)
0.8 V
CC
V
V
IL
Low-Level Input Voltage
(Note 4)
0.2 V
CC
V
I
IH
High-Level Input Current
V
IH
= V
CC
= 5.5V (Note 4)
-1.0
1.0
A
I
IL
Low-Level Input Current
V
IL
= 0V, V
CC
= 5.5V (Note 4)
-1.0
1.0
A
I
IH
Oscillator Input Current
V
IH
= V
CC
= 5.5V
100
A
I
IL
Oscillator Input Current
V
IL
= 0V, V
CC
= 5.5V
-100
A
I
Do-SOURCE
Charge Pump Output Current
V
Do
= V
P
/2, I
CPo
= LOW
(Note 3)
-1.25
mA
I
Do-SINK
V
Do
= V
P
/2, I
CPo
= LOW
(Note 3)
1.25
mA
I
Do-SOURCE
V
Do
= V
P
/2, I
CPo
= HIGH
(Note 3)
-4.25
mA
I
Do-SINK
V
Do
= V
P
/2, I
CPo
= HIGH
(Note 3)
4.25
mA
I
Do-TRI
Charge Pump
0.5V
V
Do
V
CC
- 0.5V
-5.0
5.0
nA
TRI-STATE Current
T = 25C
V
OH
High-Level Output Voltage
I
OH
= -500 A
V
CC
-
0.4
V
V
OL
Low-Level Output Voltage
I
OL
= 500 A
0.4
V
www.national.com
5
PDF 
ZIP