U2781B Datasheet, PDF (1/10 Pages) TEMIC Semiconductors – Frequency Synthesizer

Frequency Synthesizer
U2781B
Description
The programmable frequency synthesizer IC U2781B for
µP-controlled application is realized with TEMIC’s
advanced UHF process which is very suitable for
combinations of fast ECL logic and low-current I²L logic.
The benefits are high input sensitivity in connection with
low power consumption and therefore small
packages (SSO20). This makes the device a perfect
Features
D Very low current consumption (typ. 3 V/ 5 mA)
D Supply voltage range: 2.7 to 5.5 V
D Max. input frequency: 1.1 GHz
D Programmable prescaler 64/ 65 or 128/ 129
D Controlled by 3-wire bus with f_clock up to 500 kHz
D Status output for PLL lock/ unlock condition
D Very fast phase detector
D SSO20 package
D ESD protection in accordance with MIL-STD. 883
method 3015 class 2
Block Diagram
choice for cordless phones and handheld cellular radio
sets up to 1.1 GHz.
Electrostatic sensitive device.
Observe precautions for handling.
Benefits
D Very low current consumption extends talk time
D Few external components and SSO package save costs
and space
1
Osci
Osco
3
VS ₅
GND
7
Clock ₁₁
Data
13
Enable
14
Oscillator
1-bit latch
load control
RFi
10
Prescaler
64/65
128/129
14-bit
reference counter
15-bit latch
18-bit
shift register
18-bit latch
7-bit
swallow
counter
11-bit
main
counter
Phase
detector
Charge
pump
Mo
17
LDo
8
VSCP
4
CP
6
PS
15
93 7785 e
Ordering Information
Extended Type Number
U2781B-AFS
U2781B-AFSG3
Figure 1. Block diagram
Package
SS020
SS020
Remarks
Rail, MOQ 830 pcs
Tape and reel, MOQ 4000 pcs
TELEFUNKEN Semiconductors
Rev. A3, 26-Nov-97
1 (10)