BU2879AK Rohm Semiconductor, BU2879AK Datasheet - Page 3

• Manufacturer Part Number: BU2879AK
• Description: IC DRIVER FL TUBE 5V QFP44
• Manufacturer: Rohm Semiconductor

Specifications of BU2879AK

• Display Type: Vacuum Fluorescent (VF)
• Configuration: 16 Segments
• Interface: 3-Wire Serial
• Digits Or Characters: 8 Character
• Current - Supply: 5mA
• Voltage - Supply: 4.5 V ~ 5.5 V
• Operating Temperature: -25°C ~ 75°C
• Mounting Type: Surface Mount
• Package / Case: 44-QFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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Standard ICs
Supply current
Input threshold voltage
Input current
OSC oscillation frequency
Segment output current
Grid output current
Leakage current when OFF
Output pull-down resistance
Maximum operating frequency
Input data hold
Input data setup
Output data delay
Input clock cycle
Input clock "H" width
Pins descriptions
Electrical characteristics (unless otherwise noted, Ta = 25°C, V
15 ~ 25
42 ~ 39,
37 ~ 32
28 ~ 31
10 ~ 13
Pin No.
For the high voltage withstand output pins for the segment / grid of pins 26 and 28 to 31, when segment output is specified, segment output current is output, and
Serial transmission
when grid output is specified, grid current is output.
14, 38
1 ~ 4
7, 43
44
27
26,
6
5
8
9
Parameter
SW1 ~ SW4
S12 / G15
S16 / G11
G1 ~ G10
S1 ~ S11
K1 ~ K4
OSC
SCK
V
V
V
Pin
SO
CS
SI
DD
SS
EE
Power supply pin 1
Oscillation pin
Ground pin
Serial data input
Serial data output
Serial clock input
Serial chip select
High-voltage withstand
output pin for segment
Power supply pin 2
High-voltage withstand
output pin for grid
High-voltage withstand
output pin for segment / grid
Key data input pin
General-purpose input pin
Symbol
I
T
I
F
F
O
O
T
I
T
T
V
I
R
T
SCYC
OFF
I
seg
OSC
grd
MAX
DD
SW
IN
SH
SS
IN
D
D
Name
0.16
0.16
Min.
130
1.5
0.5
—
—
18
—
35
—
—
40
6
Typ.
200
—
—
—
—
—
—
70
—
—
—
—
—
—
Max.
300
140
3.5
0.3
Input / output
10
—
—
10
—
—
—
60
5
1
Output
Output
Output
Output
Input
Input
Input
Input
Input
Input
Input
Input
I / O
MHz
Unit
kHz
mA
mA
mA
k
%
V
A
A
s
s
s
s
DD
44-pin attachment, at 1000pF oscillation
Pins 1 to 4, 6, 8, 9 to 13
Pins 1 to 4, 6, 8, 9 to 13
44-pin attachment, at 1000pF oscillation
Pins 15 to 26, 28 to 31, V
Pins 26, 28 to 37, 39 to 42, V
Pins 15 to 26, 28 to 37, V
Pins 15 to 26, 28 to 37
Design guarantee value
At minimum input clock cycle
Connected to system power supply.
Capacitor connection pin for oscillation
Connected to system ground.
Serial data input starting from MSB
Serial data output starting from MSB;
output is Nch open drain.
Serial data read at rising edge.
Serial initialization when LOW, valid at HIGH.
Output pin for segment; output is
Pch open drain + pull-down resistance.
Pull-down resistance connection for FLP driver output.
Output pin for grid; output is Pch
open drain + pull-down resistance.
Used to switch output between segment and grid;
output is Pch open drain + pull-down resistance.
Data input pin for key scanning.
General-purpose input pin; input data can be
transmitted serially to microcomputer.
= 5V, V
SS
= 0V, V
Conditions
—
—
—
—
DD
Function
O
O
– V
= V
= V
O
EE
DD
DD
= V
= 35V)
– 2V
– V
DD
EE
– 2V
BU2879AK
Measurement
circuit
Fig.1
Fig.4
Fig.2
Fig.3
Fig.2
Fig.2
Fig.2
Fig.2
Fig.3
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—
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