lmx2377u National Semiconductor Corporation, lmx2377u Datasheet - Page 4

• Manufacturer Part Number: lmx2377u
• Description: Lmx2377u Pllatinum? Ultra Low Power Dual Frequency Synthesizer For Rf Personal Communications 2.5 Ghz/1.2 Ghz
• Manufacturer: National Semiconductor Corporation

www.national.com
f
D
V
IN
f
Name
OSC
IN
Clock
F
GND
GND
GND
GND
Pin Descriptions
Data
P
Vµc
o
V
Pin
NC
LE
o
Main
CC
Aux
LD
Aux
Aux
in
20-Pin UTCSP
Pin No.
10
11
12
13
14
15
16
17
18
19
—
5
6
7
8
9
24-Pin CSP
1, 9, 13, 21
Pin No.
(Continued)
10
11
12
14
15
16
17
18
19
20
22
23
6
7
8
Pin No.
TSSOP
20-Pin
10
11
12
13
14
15
16
17
18
19
20
—
6
7
8
9
I/O
— Ground for the Main PLL analog circuitry.
— Ground for the Aux PLL digital circuitry, MICROWIRE, F
— Power supply bias for the MICROWIRE circuitry. Must be ≤ V
— Ground for the Aux PLL analog circuitry.
— Ground for the Aux PLL digital circuitry, MICROWIRE, F
— Aux PLL charge pump power supply. Must be ≥ V
— Power supply bias for the Aux PLL analog and digital circuits,
— No Connect
O
O
I
I
I
I
I
I
Main prescaler complementary input. For single ended operation,
this pin should be AC grounded. The LMX2377U Main PLL can be
driven differentially when the bypass capacitor is omitted.
Reference oscillator input. It has an approximate V
threshold and can be driven from an external CMOS or TTL logic
gate.
oscillator circuits.
Programmable multiplexed output pin. Functions as a general
purpose CMOS TRI-STATE output, Main/Aux PLL open drain
analog lock detect output, N and R divider output or Fastlock
output, which connects a parallel resistor to the external loop filter.
MICROWIRE Clock input. High impedance CMOS input. Data is
clocked into the 22-bit shift register on the rising edge of Clock.
MICROWIRE Data input. High impedance CMOS input. Binary
serial data. The MSB of Data is shifted in first. The last two bits
are the control bits.
MICROWIRE Latch Enable input. High impedance CMOS input.
When LE transitions HIGH, Data stored in the shift register is
loaded into one of 4 internal control registers.
Typically connected to the same supply level as the
microprocessor or baseband controller to enable programming at
low voltages.
Aux PLL prescaler input. Small signal input from the VCO.
oscillator circuits.
Aux PLL charge pump output. the output is connected to an
external loop filter, which drives the input of the VCO.
F
Bypass capacitors should be placed as close as possible to this
pin and be connected directly to the ground plane.
o
4
LD, and oscillator circuits. V
Description
CC
may range from 2.7V to 5.5V.
CC
CC
.
/2 input
o
o
LD, and
LD, and
CC
.