M5482B7 STMicroelectronics, M5482B7 Datasheet - Page 4

• Manufacturer Part Number: M5482B7
• Description: IC LED DISPLAY DRIVER 20-PDIP
• Manufacturer: STMicroelectronics

Specifications of M5482B7

• Display Type: LED
• Configuration: 7 Segment
• Interface: Serial
• Digits Or Characters: 2 Digits
• Current - Supply: 7mA
• Voltage - Supply: 4.75 V ~ 13.2 V
• Operating Temperature: -25°C ~ 85°C
• Mounting Type: Through Hole
• Package / Case: 20-DIP (0.300", 7.62mm)
• Number Of Digits: 2
• Number Of Segments: 15
• Operating Supply Voltage: 4.75 V to 13.2 V
• Maximum Supply Current: 7 mA
• Maximum Power Dissipation: 1.5 W
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• Minimum Operating Temperature: - 25 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

M5482
Figure 4. Input Data Format
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 al-
lowing 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.
Figure 5 shows the timing relationships between
Data and Clock.
A maximum clock frequency of 0.5 MHz is as-
sumed.
Table 3 shows the Output Data Format for the
M5482. Because it uses only 15 of the possible 35
outputs, 20 of the bits are "Don’t Cares".
For applications where a lesser number of outputs
are used it is possible to either increase the cur-
rent per output or operate the part at higher than
1V V
Table 3. Serial Data Bus / Outputs Correspondence
4/10
5451
5482
5451
5482
OUT
.
35
15
17
X
CLOCK
DATA
LOAD
(INTERNAL)
RESET
(INTERNAL)
34
X
16
8
33
X
15
7
32
X
14
6
START
31
1
X
13
5
30
14
BIT 1
12
X
29
13
11
X
28
X
10
X
27
X
X
9
26
X
The following equation can be used for calcula-
tions.
T
(80 °C/W) + T
where:
T
V
I
80 °C/W = thermal coefficient of the package
T
Figure 5.
LED
j
j
amb
OUT
… [(V
≡ junction temperature (150 °C max)
CLOCK
DATA
8
4
25
X
= the LED current
= ambient temperature
= the voltage at the LED driver outputs
7
3
OUT
24
12
)(I
6
2
BIT 34
amb
23
11
LED
)(no.of segments) + V
5
1
BIT 35
22
10
36
X
4
21
9
X
3
20
X
19
X
2
X
300ns (min.)
18
X
X
1
DD
. 7 mA]
START
START
START
START