DS1670 Datasheet, PDF (1/16 Pages) Dallas Semiconductor – Portable System Controller

www.maxim-ic.com
GENERAL DESCRIPTION
The DS1670 portable system controller is a circuit
that incorporates many of the functions necessary for
low-power portable products integrated into one chip.
The device provides a real-time clock (RTC), NV
RAM controller, microprocessor monitor, and a
3-channel, 8-bit analog-to-digital converter (ADC).
Communication with the DS1670 is established
through a simple 3-wire interface.
The RTC provides seconds, minutes, hours, day,
date, month, and year information with leap year
compensation. The RTC also provides an alarm
interrupt. This interrupt works when the DS1670 is
powered by the system power supply or when in
battery-backup operation, so the alarm can be used to
wake up a system that is powered down.
Automatic backup and write protection of an external
SRAM is provided through the V_CCO, CEOL, and
CEOH pins. The backup energy source used to power
the RTC is also used to retain RAM data in the
absence of V_CC through the V_CCO pin. The chip-
enable outputs to RAM (CEOL and CEOH) are
controlled during power transients to prevent data
corruption.
ORDERING INFORMATION
PART*
VOLTAGE PIN-
(V) PACKAGE
TOP MARK†
DS1670E
3.3 20 TSSOP DS1670E
DS1670E+
3.3 20 TSSOP DS1670E
DS1670E/T&R 3.3 20 TSSOP DS1670E
DS1670E+TRL 3.3 20 TSSOP DS1670E
DS1670S
3.3 20 SO
DS1670S
DS1670S+
3.3 20 SO
DS1670S
* All devices are specified over the 0°C to +70°C operating range.
† A “‘+” anywhere on the top mark denotes a lead-free device.
+ Denotes a lead-free/RoHS-compliant device.
DS1670
Portable System Controller
FEATURES
§ Provides Real-Time Clock
Counts Seconds, Minutes, Hours, Date of the
Month, Month, Day of the Week, and Year
with Leap Year Compensation Valid Up to
2100
Power-Control Circuitry Supports System
Power-On from Day/Time Alarm
§ Microprocessor Monitor
Halts Microprocessor During Power Fail
Automatically Restarts Microprocessor after
Power Failure
Monitors Pushbutton for External Override
Halts and Resets an Out-of-Control
Microprocessor
§ NV RAM Control
Automatic Battery Backup and Write Protection
to External SRAM
§ 3-Channel, 8-Bit ADC
§ Simple 3-Wire Interface
§ 3.3V Operation
§ Underwriters Laboratory (UL) Recognized
PIN CONFIGURATION
TOP VIEW
VBAT
VCCO
SCLK
I/O
CS
CEI
CEOL
CEOH
INT
GND
1
20
DS1670
2
19
3
18
4
17
5
16
6
15
7
14
8
13
9
12
10
11
ST
VCC
X1
X2
AIN0
AIN1
AIN2
RST
BLE
BHE
TSSOP (4.4mm)
SO (300 mils)
1 of 16
REV: 080805