5616
5616
Data Sheet
26110
2-FUNCTION, 4-DIGIT LCD AUTOMOTIVE CLOCK
The SCL5616HW is a 2-function digital automotive clock circuit.
Fabricated on a single monolithic chip using silicon-gate CMOS PROM
technology, it offers low cost, low power, and high reliability. It also
includes digital frequency correction, stored in the internal nonvolatile
memory, for easy adjustment of the oscillator nominal frequency.
adge1
AM
PM
BACKPLANE
b1
g2
f2
a2
2-FUNCTION, 4-DIGIT
LCD AUTOMOTIVE CLOCK—PROGRAMMABLE
b2
c1
COLON
e2
g3
d2
f3
c2
ad3
e3
2040 x 3040 µm
b3
U
e4
f4
d4
D
FEATURES
P
O
R
E
C
N
O
■ Digital Tuning of Crystal Frequency
■ PROM for Storing Frequency Correction Information
■ 12 or 24 Hour Timekeeping Option
■ Flashing Colon
■ Two Switches Control All Setting Functions
■ High Noise Immunity
■ Internal Power-Up Reset Circuitry
■ Internal Voltage Regulation
D
E N
U E
N ER
I
T F
N E
O
R
C
R
S
I
O
D F
—
a4
c4
S2
b4
SELECT
S1
GROUND
{
OSC.
GROUND
NU
VPP
NU
IGNITION
VDD
DATA
Y
L
The SCL5616HW is supplied in wafer form and is rated for
continuous operation over the automotive temperature range of
-40°C to +85°C.
c3
0.080 x 0.120 in
g4
T
C
Dwg. No. PC-001
ABSOLUTE MAXIMUM RATINGS
Supply Current, IDD .......................... 2.0 mA
Input Voltage Range, VIN
(except VPP) ...................... -0.3 V to VDD
(Programming
Power Voltage, VPP) .................. 18.5 V
Input Current (except VPP), IIN ......... ±10 mA
Power Dissipation, PD ................... 300 mW
Operating Temperature Range,
TA .................................. -40°C to +85°C
Storage Temperature Range,
TS ................................ -65°C to +150°C
Caution: These CMOS devices have static protection, but are susceptible to damage if exposed
to extremely high static electrical charges.
Always order by complete part number:
SCL5616HW .
5616
2-FUNCTION, 4-DIGIT LCD AUTOMOTIVE CLOCK
TYPICAL APPLICATION
6.8 kΩ
4.194304 MHz
CL = 15 pF, RS = 50 Ω
IGNITION
+12 V
VDD
1 MΩ
MINUTES
+
47 µF
BACKPLANE
AM
S2
SEGMENTS
HOURS
PM
S1
GROUNDS
Dwg. EC-001
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
W
Copyright © 1990, 1995, Allegro MicroSystems, Inc.
5616
2-FUNCTION, 4-DIGIT LCD AUTOMOTIVE CLOCK
ELECTRICAL CHARACTERISTICS at TA = -40°C to +85°C, in Typical Application
(unless otherwise noted).
Limits
Characteristic
Symbol
Test Conditions
Min.
Typ.
Max.
Units
Operating Voltage Range
VDD
TA = +25°C
4.5
—
—
V
Zener Voltage
VDD
IDD = 1.0 mA
5.5
—
6.8
V
Segment Output Current
IOUT
VDD = 5.0 V, VOUT = 4.8 V
-20
—
—
µA
VDD = 5.0 V, VOUT = 0.2 V
120
—
—
µA
VDD = 5.0 V, VOUT = 4.8 V
-80
—
—
µA
VDD = 5.0 V, VOUT = 0.2 V
240
—
—
µA
VDD ≥5.0 V
4.0
—
—
V
S1, S2, DATA, or SELECT
-55
—
-700
µA
—
4.194 304
—
MHz
VDD = Zener voltage
—
—
200
ms
∆VDD = ±100 mV
—
—
±1.0
ppM
Backplane Output Current
LCD Drive Signal
Input Current
IOUT
VDISP
IIN
Oscillator Frequency
fOSC
Oscillator Starting Time
tOSC
Oscillator Stability
∆fOSC
Backplane Frequency
fBP
—
64
—
Hz
Switch Debounce Time
tDB
0
—
62.5
ms
Osc. Feedback Resistance
ROSC
—
16
—
MΩ
Osc. Input Capacitance
COSCI
—
15
—
pF
Osc. Output Capacitance
COSCO
—
30
—
pF
—
—
1.0
mA
Supply Current
IDD
VDD = 5.0 V
NOTE: Negative current is defined as coming out of (sourcing) the specified device terminal.
DISPLAY FORMAT
a1
AM
a2
b1
f2
a3
b2
g1
f3
g2
a4
b3
g3
f4
c3
e4
b4
g4
COLON
PM
e1
c1
d1
e2
c2
d2
e3
d3
c4
d4
Dwg. No. OC-001
5616
2-FUNCTION, 4-DIGIT LCD AUTOMOTIVE CLOCK
FUNCTIONAL DESCRIPTION
DATA Logic Levels are VDD and Ground
Power-Up Reset. When power up occurs, the hours and minutes
counters are reset, and the clock starts running:
Operation
12-Hour mode and counting starts from 1:00 AM
Programming Modes. Data is loaded by pulling DATA low (1 µs pulse
duration) n times to set the desired bits for frequency correction into
the data input register. This information is latched in the RAM, thus
allowing the testing of the oscillator frequency adjustment without
storing the selected pattern in the PROM cells. The data latched in the
RAM is stored in the PROM cells when DATA is held low for a minimum of 10 ms.
The data stored in the data input register is cleared on any SELECT
transition (low to high or high to low). It is also cleared when the
program power voltage (VPP) is reduced from 18 V to VDD. Clearing the
data input register does not affect the data latched in the RAM.
Program
VPP
DATA
VD
SELECT
VS
18 V
18 V
VDD
Pulse
Ground
VDD
Ground
VDD
Ground
Operation
DATA load for frequency correction
DATA store
Verify stored data
FREQUENCY CORRECTION
FREQUENCY CORRECTION
VPP
t PHDL
1
2
t wD
t DHPL
3
t DLH
127 MAX
VD
t DHL
t PLSX
VS
t SVDL
VERIFY CYCLE (VPP = VDD )
VS
t SLDV
t SHDX
SEGMENT OUTPUTS
Dwg. No. WC-001-1
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
5616
2-FUNCTION, 4-DIGIT LCD AUTOMOTIVE CLOCK
Frequency Correction. The on-chip oscillator circuit increases the
crystal frequency approximately 40 ppm. This ensures that the typical
crystal will operate within the tuning range. With VS at ground, data
pulses are then used to trim the internal clock frequency by 2 to 254
ppm to the required value. The quantity of data pulses needed (1 to
127) is
n=
fBP - 64
128 x 10-6
where fBP is the measured frequency at BACKPLANE. Prior to trimming, it must be between 64.000 128 Hz and 64.016 256 Hz.
Operating Modes. The operating modes of the clock are controlled
by the voltages applied to VPP, SELECT, IGNITION, and switches S1
and S2.
Program
VPP
VDD
VDD
18 V
SELECT
VS
S1
S2
IGNITION
VDD
VDD
Ground
Open
Ground
Open
Open
Ground
Open
X
12 V
X
Mode
Clock running
Diagnostic
Programming
X = Irrelevant, ground or 12 V
Clock Running Mode. During the clock running mode, setting
functions are achieved by either momentary or continuous operation
of switches S1 and S2, which are enabled by IGNITION. Hours or
minutes are incremented on S1 or S2 (respectively) depression and
continue at a 1 Hz rate while the switch is depressed.
S1
S2
Open
Open
X
X
Ground Open
Open
Ground
Ground Ground
IGNITION
X
Ground
12 V
12 V
12 V
Operation
Clock running
Setting disabled
Set hours
Set Minutes
Change counting sequence (12 to 24 hour
or 24 to 12 hour)
X = Irrelevant, ground or 12 V for IGNITION, ground or open for S1 and S2
Diagnostic Mode. To enter the diagnostic mode, S1 and S2 are operated with IGNITION connected to 12 V. All segments are displayed for
as long as S1 and S2 are depressed. On opening S1 and S2, the clock
will leave the diagnostic mode and go through a power-up sequence.
In the SCL5616HW, the counting sequence will change (from 12 hour
to 24 hour or from 24 hour to 12 hour). To inhibit the power-up reset,
hold the DATA input low (ground). The counting mode will change
without resetting the hours or minutes counters.
5616
2-FUNCTION, 4-DIGIT LCD AUTOMOTIVE CLOCK
Stored Data Verification. In the verify mode, the complement value
of the information stored in the PROM cells is brought out directly to
the segment output terminals for easy verification of the stored data.
If a bit is programmed (high), the appropriate segment output is turned
ON (low). The segments represent the binary equivalent of the
number of frequency correction data pulses entered.
Frequency Selection Pulses
Segment
64
b4
32
c4
16
d4
8
e4
4
c3
2
e3
1
c2
RECOMMENDED FLASH
PROGRAMMING CHARACTERISTICS
at TA = +25°C, Logic Levels are VDD and Ground
(except PROGRAM High)
Characteristic
Symbol
Min.
PROGRAM High (18 V) to DATA Low
tPHDL
1.0
—
µs
SELECT Valid to DATA Low
tSVDL
25
—
µs
DATA Low to DATA High
tDLH
1.0
1.5
µs
DATA High to DATA Low
tDHL
1.0
—
µs
DATA Store Pulse Duration
twD
10
—
ms
DATA High to PROGRAM Low
tDHPL
1.0
—
µs
PROGRAM Low to SELECT Change
tPLSX
1.0
—
µs
SELECT Low (Verify) to DATA Valid
tSLDV
—
1.0
µs
DATA Hold from End of Verify
tSHDX
—
10
ns
Allegro MicroSystems, Inc. reserves the right to
make, from time to time, such departures from the detail
specifications as may be required to permit improvements in the design of its products.
The information included herein is believed to be
accurate and reliable. However, Allegro MicroSystems,
Inc. assumes no responsibility for its use; nor for any
infringements of patents or other rights of third parties
which may result from its use.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Max. Units