Data Sheet
26185.202
8-BIT SERIAL-INPUT, CONSTANT-
CURRENT LATCHED LED DRIVER
Always order by complete part number, e.g., A6277EA .
The A6277x is specifically designed for LED-display applications.
Each BiCMOS device includes an 8-bit CMOS shift register, accompa-
nying data latches, and eight npn constant-current sink drivers. Two
package styles and two operating temperature ranges are available.
The CMOS shift register and latches allow direct interfacing with
microprocessor-based systems. With a 5 V logic supply, typical serial
data-input rates are up to 20 MHz. The LED drive current is deter-
mined by the user’s selection of a single resistor. A CMOS serial data
output permits cascade connections in applications requiring additional
drive lines. For inter-digit blanking, all output drivers can be disabled
with an ENABLE input high. In addition, a HIGH/LOW function
enables full selected current with the application of a logic low, or 50%
selected current with the application of a logic high.
The first character of the part number suffix determines the device
operating temperature range. Suffix ‘E–’ is for -40°C to +85°C, and
suffix ‘S–’ is -20°C to +85°C. Two package styles are provided for
through-hole DIP (suffix ‘–A’) or surface-mount SOIC (suffix ‘–LW’)
applications. The copper lead frame and low logic-power dissipation
allow the dual in-line package to sink 122 mA through all outputs
continuously over the operating temperature range (1.0 V drop,
+85°C).
Note that the A6277EA (DIP) and the A6277ELW
(SOIC) are electrically identical and share a
common terminal number assignment.
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, V
DD
...................... 7.0 V
Output Voltage Range,
V
O
............................ -0.5 V to +24 V
Output Current, I
O
....................... 150 mA
Input Voltage Range,
V
I
.................... -0.4 V to V
DD
+ 0.4 V
Package Power Dissipation,
P
D
..................................... See Graph
Operating Temperature Range, T
A
Suffix ‘S-’ ................ -20°C to +85°C
Suffix ‘E-’ ................ -40°C to +85°C
Storage Temperature Range,
T
S
........................... -55°C to +150°C
Caution: These CMOS devices have input
static protection (Class 2) but are still suscep-
tible to damage if exposed to extremely high
static electrical charges.
6277
PRELIMINARY INFORMATION
(Subject to change without notice)
July 20, 2000
FEATURES
a73 To 150 mA Constant-Current Outputs
a73 24 V Outputs
a73 Under-Voltage Lockout
a73 Low-Power CMOS Logic and Latches
a73 High Data Input Rate
a73 Similar to Toshiba TD62715FN
a73 High/Low Output Current Function
A6277ELW
REGISTER
LATCHES
5
10 11
12
13
14
156
7
8
9
16
POWER
GROUND
POWER
GROUND
HIGH/LOW
(CURRENT)
OUT
1
OUT
2
Dwg. PP-029-17A
OUT
0
OUT
4
OUT
6
OUT
5
OUT
3
OUT
7
LOGIC
GROUND
1
2
3
17
19
4
18
20
SERIAL
DATA OUT
LOGIC
SUPPLY
SERIAL
DATA IN
OUTPUT
ENABLE
LATCH
ENABLE
CLOCK
CK
V
DD
OE
R
EXT
I
REGULATOR
L
O
SUB SUB
SERIAL
DATA OUT
2
1
FF