STMicroelectronics M5450 Led display driver Datasheet

M5450
M5451
LED DISPLAY DRIVERS
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.
..
..
.
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M5450 34 OUTPUTS/15mA SINK
M5451 35 OUTPUTS/15mA SINK
CURRENT GENERATOR OUTPUTS (NO EXTERNAL RESISTORS REQUIRED)
CONTINUOUS BRIGHTNESS CONTROL
SERIAL DATA INPUT
ENABLE (ON M5450)
WIDE SUPPLY VOLTAGE OPERATION
TTL COMPATIBILITY
Application Examples :
MICROPROCESSOR DISPLAYS
INDUSTRIAL CONTROL INDICATOR
RELAY DRIVER
INSTRUMENTATION READOUTS
A single pin controls the LED display brightness by
setting a reference current through a variable resistor connected to VDD or to a separate supply of
13.2V maximum.
DIP40
(Plastic Package)
ORDER CODE : M5450B7 / M5451B7
DESCRIPTION
The M5450 and M5451 are monolithic MOS integrated circuits produced with an N-channel silicon
gate technology. They are available in 40-pin dual
in-line plastic packages.
PLCC44
(Plastic Chip Carrier)
ORDER CODE : M5451Q
PIN CONNECTION
8
OUTPUT BIT 10
9
OUTPUT BIT 13
7
39
OUTPUT BIT 23
OUTPUT BIT 12
8
38
OUTPUT BIT 24
OUTPUT BIT 24
OUTPUT BIT 11
9
37
OUTPUT BIT 25
33
OUTPUT BIT 25
OUTPUT BIT 10
10
36
OUTPUT BIT 26
32
OUTPUT BIT 26
OUTPUT BIT 9
11
35
OUTPUT BIT 27
N.C.
12
34
N.C.
OUTPUT BIT 8
13
33
OUTPUT BIT 28
OUTPUT BIT 5
16
30
OUTPUT BIT 31
OUTPUT BIT 4
17
29
OUTPUT BIT 32
OUTPUT BIT 5
14
27
OUTPUT BIT 31
OUTPUT BIT 4
15
26
OUTPUT BIT 32
OUTPUT BIT 3
16
25
OUTPUT BIT 33
OUTPUT BIT 2
17
24
OUTPUT BIT 1
18
23
OUTPUT BIT 34
DATA ENABLE FOR M5450
OUTPUT BIT 35 FOR M5451
BRIGHTNESS CONTROL
19
22
DATA IN
V DD
20
21
CLOCK IN
September 1993
28
OUTPUT BIT 30
OUTPUT BIT 33
28
27
13
OUTPUT BIT 34
OUTPUT BIT 30
OUTPUT BIT 6
26
31
OUTPUT BIT 35
15
25
OUTPUT BIT 6
DATA IN
OUTPUT BIT 29
24
29
CLOCK IN
12
23
OUTPUT BIT 29
OUTPUT BIT 7
N.C.
32
22
14
VDD
OUTPUT BIT 7
21
OUTPUT BIT 28
BRIGHTNESS CONTROL
30
20
11
OUTPUT BIT 1
OUTPUT BIT 8
19
OUTPUT BIT 27
18
31
OUTPUT BIT 2
10
OUTPUT BIT 3
OUTPUT BIT 9
5450-01.EPS - 5450-02.EPS
OUTPUT BIT 11
OUTPUT BIT 22
34
OUTPUT BIT 21
7
40
OUTPUT BIT 12
OUTPUT BIT 20
OUTPUT BIT 23
41
35
OUTPUT BIT 19
6
42
OUTPUT BIT 22
OUTPUT BIT 13
OUTPUT BIT 18
36
43
5
N.C.
OUTPUT BIT 21
OUTPUT BIT 14
44
37
VSS
4
1
OUTPUT BIT 20
OUTPUT BIT 15
OUTPUT BIT 17
38
2
3
OUTPUT BIT 16
OUTPUT BIT 19
OUTPUT BIT 16
3
OUTPUT BIT 18
39
OUTPUT BIT 15
40
2
4
1
OUTPUT BIT 14
V SS
OUTPUT BIT 17
5
PLCC44
6
DIP40
1/8
M5450 - M5451
BLOCK DIAGRAM (Figure 1)
V DD
BRIGTHNESS
CONTROL
20
OUTPUT
BIT 34
OUTPUT
BIT 1
24
18
100kΩ
19
35 OUTPUT BUFFERS
LOAD
35 LATCHES
DATA ENABLE (M5450)
OUTPUT35
(M5451)
23
SERIAL
DATA
22
CLOCK
21
35-BIT SHIFT REGISTER
5450-03.EPS
RESET
1
Symbol
VDD
VI
VO(off)
IO
Ptot
Tj
Value
Unit
Supply Voltage
Parameter
– 0.3 to 15
V
Input Voltage
– 0.3 to 15
V
Off State Output Voltage
15
V
Output Sink Current
40
mA
Total Package Power Dissipation at 25°C
at 85°C
1
560
W
mW
Junction Temperature
150
°C
Top
Operating Temperature Range
– 25 to 85
°C
Tstg
Storage Temperature Range
– 65 to 150
°C
Stresses above those listed under "Absolute Maximum Ratings" may causes permanent damage to the device. This is a stress rating only and
functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not
implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
FUNCTIONAL DESCRIPTION
Both the M5450 and the M5451 are specially designed to operate 4 or 5-digit alphanumeric displays
with minimal interface with the display and the data
source. Serial data transfer from the data source to
the display driver is accomplished with 2 signals,
serial data and clock. Using a format of a leading
"1" followed by the 35 data bits allows data transfer
without an additional load signal. The 35 data bits
are latched after the 36th bit is complete, thus
providing non-multiplexed, direct drive to the display.
Outputs change only if the serial data bits differ
from the previous time.
Display brightness is determined by control of the
output current LED displays.
2/8
A 1nF capacitor should be connected to brightness
control, pin 19, to prevent possible oscillations.
A block diagram is shown in figure 1. For the M5450
a DATA ENABLE is used instead of the 35th output.
The DATA ENABLE input is a metal option for the
M5450.
The output current is typically 20 times greater than
the current into pin 19, which is set by an external
variable resistor. There is an internal limiting resistor of 400Ω nominal value.
Figure 2 shows the input data format. A start bit of
logical "1" precedes the 35 bits of data. At the 36th
clock a LOAD signal is generated synchronously
with the high state of the clock, which loads the 35
bits of the shift registers into the latches.
5450-01.TBL
ABSOLUTE MAXIMUM RATINGS
M5450 - M5451
At the low state of the clock a RESET signal is
generated which clears all the shift registers for the
next set of data. The shift registers are static master-slave configurations. There is no clear for the
master portion of the first shift register, thus allowing continuous operation.
There must be a complete set of 36 clocks or the
shift registers will not clear.
When power is first applied to the chip an internal
power ON reset signal is generated which resets
all registers and all latches. The START bit and the
first clock return the chip to its normal operation.
Bit 1 is the first bit following the start bit and it will
appear on Pin 18. A logical "1" at the input will turn
on the appropriate LED.
Figure 3 shows the timing relationship between
Data, Clock and DATA ENABLE.
A max clock frequency of 0.5MHz is assumed.
For applications where a lesser number of outputs
are used, it is possible to either increase the current
per output or operate the part at higher than 1V
VOUT.
The following equation can be used for calculations.
Tj = [(VOUT) (ILED) (No. of segments) + (VDD ⋅ 7mA)]
(124°C/W) + Tamb
where :
Tj = junction temperature (150°C max)
VOUT = the voltage at the LED driver outputs
ILED = the LED current
124°C/W = thermal coefficient of the package
Tamb = ambient temperature
The above equation was used to plot Figures 4, 5
and 6.
STATIC ELECTRICAL CHARACTERISTICS
(Tamb within operating range, VDD = 4.75V to 13.2V, VSS = 0V, unless otherwise specified)
Parameter
VDD
Supply Voltage
IDD
Supply Current
VI
Input Voltage
IB
Brightness Input Current (note 2)
VB
Brightness Input Voltage (pin 19)
VO(off)
IO
fclock
IO
Notes : 1.
2.
3.
4.
Test Conditions
Min.
Typ.
4.75
Max.
13.2
V
7
mA
- 0.3
2.2
VDD - 2
0.8
VDD
VDD
V
V
V
0
0.75
mA
3
4.3
V
13.2
V
10
µA
10
4
25
µA
mA
mA
0.5
MHz
± 20
%
VDD = 13.2V
Logical "0" Level
Logical "1" Level
± 10µA Input Bias
4.75 ≤ VDD ≤ 5.25
VDD > 5.25
Input Current = 750µA,
Tamb = 25oC
Off State Out. Voltage
Out. Sink Current (note 3)
Segment OFF
Segment ON
Input Clock Frequency
Output Matching (note 1)
VO = 3V
VO = 1V (note 4)
Brightness In. = 0µA
Brightness In. = 100µA
Brightness In. = 750µA
Unit
0
2
12
2.7
15
0
Output matching is calculated as the percent variation from IMAX + IMIN/2.
With a fixed resistor on the brightness input some variation in brightness will occur from one device to another.
Absolute maximum for each output should be limited to 40mA.
The VO voltage should be regulated by the user. See figures 5 and 6 for allowable VO versus IO operation.
3/8
5450-02.TBL
Symbol
M5450 - M5451
Figure 2 : Input Data Format
1
36
CLOCK
START
BIT 1
BIT 34
BIT 35
DATA
5450-04.EPS
LOAD
(INTERNAL)
RESET
(INTERNAL)
Figure 3
Figure 4
1.0
Ptot (W)
15mA/segment
34 segments
VO = 1V
CLOCK
0.8
0.6
DATA
300ns (min.)
0.4
DATA ENABLE
Figure 5
T amb (˚C)
20
0
80
100
I 0 (mA)
VO (V)
105
T amb = 85˚C
2.0
I O (max.) = 40mA
85
65
VO = 1V
VO = 1.5V
VO = 2V
1.6
45
1.2
0.8
T amb = 85˚C
0.4
T j = 150˚C (max.)
8
12
16
20
24
28
32
5450-07.EPS
4
25
I LED (mA)
N˚ Segm.
5
0
4
8
12 16 20 24 28 32 36 40
5450-08.EPS
20 segments
30 segments
34 segments
2.4
4/8
60
Figure 6
2.8
0
40
5450-06.EPS
5450-05.EPS
0.2
100ns (min.)
3.2
SAFE OPERATING
AREA
M5450 - M5451
TYPICAL APPLICATIONS
BASIC ELECTRONICALLY TUNED RADIO OR TV SYSTEM
AM
FM
34 SEGMENTS
M5450
DISPLAY
DRIVER
ELECTRONIC
TUNING
CONTROLLER
PLL
SYNTHESIZER
5450-09.EPS
KEYBOARD
STATION
DETEC. ETC.
DUPLEXING 8 DIGITS WITH ONE M5450
V DD
V LED
.
9 16
.
28 40
V DD
V LED
.
32 39
.
.
.
.
.
24 31
M5450
18
21
22
19
20
1
23
17
CLOCK IN
DATA IN
5450-10.EPS
V DD
BRIGHTNESS
CONTROL
5/8
M5450 - M5451
nected diodes is quite stable if the diodes are
properly chosen.
The total power dissipation of the IC depends, in a
first approximation, only on the number of segments activated.
POWER DISSIPATION OF THE IC
The power dissipation of the IC can be limited using
different configurations.
a) In the application R must be chosen taking into
account the worst operating conditions.
b)
+V C
a)
+V C
R
ID
VD
R is determined by the maximum number of segments activated
VC − VD MAX − VO MIN
R=
NMAX ⋅ ID
The worst case condition for the device is when
roughly half of the maximum number of segments
are activated.
It must be checked that the total power dissipation
does not exceed the absolute maximum ratings of
the device.
In critical cases more resistors can be used in
conjunction with groups of segments.
In this case the current variation in the single
resistor is reduced and Ptot limited.
b) In this configuration the drop on the serial con-
6/8
5450-12.EPS
c) In this configuration VOUT + VD is constant. The
total power dissipation of the IC depends only on
the number of segments activated.
c)
+VC
V OUT +V D
5450-13.EPS
5450-11.EPS
V OUT
M5450 - M5451
I
L
a1
PACKAGE MECHANICAL DATA
40 PINS - PLASTIC DIP
b1
b
b2
e
E
e3
D
21
1
20
a1
b
b1
b2
D
E
e
e3
F
i
L
Min.
Millimeters
Typ.
0.63
0.45
0.23
Max.
Min.
0.31
0.009
1.27
2.54
48.26
0.012
2.070
0.657
0.598
0.100
1.900
14.1
4.445
3.3
Max.
0.050
52.58
16.68
15.2
Inches
Typ.
0.025
0.018
0.555
DIP40.TBL
Dimensions
PM-DIP40.EPS
F
40
0.175
0.130
7/8
M5450 - M5451
PACKAGE MECHANICAL DATA
44 PINS - PLASTIC CHIP CARRIER
C
B
M
M1
6
1 44
2
39
M
38
e3
F1
E
e
F
M1
7
17
29
18
28
d2
A
G (Seating Plane Coplanarity)
A
B
C
D
d1
d2
E
e
e3
F
F1
G
M
M1
Min.
17.4
16.51
3.65
4.2
2.59
Millimeters
Typ.
Max.
17.65
16.65
3.7
4.57
2.74
Min.
0.685
0.650
0.144
0.165
0.102
16
0.590
0.68
14.99
D
Inches
Typ.
Max.
0.695
0.656
0.146
0.180
0.108
0.027
1.27
12.7
0.46
0.71
0.630
0.050
0.500
0.018
0.028
0.101
1.16
1.14
0.004
0.046
0.045
Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility
for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result
from its use. No licence is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics.
Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all
information previously supplied. SGS-THOMSON Microelectronics products are not authorized for use as critical components in life
support devices or systems without express written approval of SGS-THOMSON Microelectronics.
© 1994 SGS-THOMSON Microelectronics - All Rights Reserved
Purchase of I2C Components of SGS-THOMSON Microelectronics, conveys a license under the Philips
I2C Patent. Rights to use these components in a I2C system, is granted provided that the system conforms to
the I2C Standard Specifications as defined by Philips.
SGS-THOMSON Microelectronics GROUP OF COMPANIES
Australia - Brazil - China - France - Germany - Hong Kong - Italy - Japan - Korea - Malaysia - Malta - Morocco
The Netherlands - Singapore - Spain - Sweden - Switzerland - Taiwan - Thailand - United Kingdom - U.S.A.
8/8
PLCC44.TBL
Dimensions
PMPLCC44.EPS
d1
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