DS32KHZSN Maxim Integrated Products, DS32KHZSN Datasheet - Page 6

• Manufacturer Part Number: DS32KHZSN
• Description: Timers & Support Products 32.768kHz Push-Pull TXCO Crystal Oscilla
• Manufacturer: Maxim Integrated Products

Specifications of DS32KHZSN

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The DS32kHz is packaged in a 36-pin ball grid array (BGA). It also is available in a 16-pin 0.300” SO and a 14-pin
encapsulated DIP (EDIP) module.
The additional PC board space required to add the DS32kHz as an option for driving a RTC is negligible in many
applications (see
use of the DS32kHz where applications require improved timekeeping accuracy.
Figure 3. Block Diagram
OPERATION
The DS32kHz module contains a quartz tuning-fork crystal and an IC. When power is first applied, and when the
device switches between supplies, the DS32kHz measures the temperature and adjusts the crystal load to
compensate the frequency. The power supply must remain at a valid level whenever a temperature measurement
is made, including when V
64 seconds and adjusts the crystal load.
The DS32kHz is designed to operate in two modes. In the dual-supply mode, a comparator circuit, powered by V
monitors the relationship between the V
V
while V
In the single-supply mode, V
because the comparator circuit is unpowered
Figure 4A
4.5V and 5.5V, and V
only a single-supply system is available. V
5.5V. The V
held at +5V. See the frequency stability vs. operating voltage for information about frequency error vs. supply
voltage.
BAT
V
BAT
, the device switches over to V
CC
Switching
Power
Circuit
is applied.
shows how the DS32kHz should be connected when using two power supplies. V
BAT
GND
V
pin should be connected directly to a battery.
CC
Figure
BAT
should be between 2.7V and 3.5V.
6) Therefore, adding the DS32kHz to new designs and future board revisions allows the
Measurement
Temperature
Power Control
CC
CC
is first applied. While powered, the DS32kHz measures the temperature once every
is grounded and the unit is powered by V
BAT
Semiconductor
(Figure
DS32kHz
CC
Dallas
and V
CC
(Figure
should be grounded and V
4A). This mode uses V
P
N
BAT
32.768kHz
input levels. When V
4B).
6 of 8
Figure 4B
Figure 4C
CC
shows how the DS32kHz can be used when
to conserve the battery connected to V
BAT
CC
BAT
shows a single-supply mode where V
. Current consumption is less than V
drops below a certain level compared to
should then be held between 2.7V and
CC
should be between
BAT
CC
CC
CC
,
is
,