DS8615 DS8616 130 225 MHz Low Power Dual Modulus Prescalers
July 1992
DS8615 DS8616 130 225 MHz
Low Power Dual Modulus Prescalers
General Description
The DS8615 series products are low power dual modulus
prescalers which divide by 32 33 and 40 41 respectively
The modulus control (MC) input selects division by N when
at a high TTL level and division by N
a
1 when at a low TTL
level The clock inputs are buffered providing 40 100
mVrms input sensitivity The two outputs provide the user
the option to wire either a totem-pole or open-collector out-
put structure Additionally the user can wire a resistor be-
tween the two output pins to minimize edge transition emis-
sions The outputs are designed to drive positive edge trig-
gered PLLs These products can be operated from either an
unregulated 5 5V to 13 5V source or regulated 5V
g
10%
source Unregulated operation is obtained by connecting V
S
to the source with V
REG
open Regulated operation is ob-
tained by connecting both V
S
and V
REG
to the supply
source
The device can be used in phase-locked loop applications
such as FM radio or other communications bands to pre-
scale the input frequency down to a more usable level A
digital frequency display system can also be derived sepa-
rately or in conjunction with a phase-locked loop and it can
extend the useful range of many inexpensive frequency
counters to 225 MHz
Features
Y
Y
Y
Y
Y
Input frequency 130 MHz (-4) 225 MHz (-2)
Low power 10 mA (-4 -2)
Input sensitivity 100 mVrms (-4) 40 mVrms (-2)
Pin compatible with Motorola MC12015-16 prescalers
Unregulated regulated power supply option
Logic and Connection Diagrams
Generalized
d
N N
a
1
TL F 5240 鈥?1
Dual-In-Line Package
TL F 5240 鈥?2
Top View
Order Number DS8615N or DS8616N (-4 -2)
See NS Package Number N08E
C
1995 National Semiconductor Corporation
TL F 5240
RRD-B30M105 Printed in U S A
1
2
3
4
5
6
7
