Allegro A6275SLW, A6275SA, A6275ELW, A6275EA Datasheet

A6275ELW

Data Sheet

26185.200

8-BIT SERIAL-INPUT, CONSTANT­CURRENT LATCHED LED DRIVER

Always order by complete part number, e.g., A6275EA .

The A6275EA and A6275ELW are specifically designed for LED­display applications. Each BiCMOS device includes an 8-bit CMOS
shift register, accompanying data latches, and eight npn constant­current sink drivers. Except for package style and allowable package
power dissipation, the two devices are identical.

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 deter­mined 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. Similar 16-bit devices are available as
the A6276EA and A6276ELW.

Two package styles are provided for through-hole DIP (suffix A) or
surface-mount SOIC (suffix LW). Under normal applications, copper
lead frames and low logic-power dissipation allow these devices to
sink maximum rated current through all outputs continuously over the
operating temperature range (90 mA, 0.9 V drop, +85°C). Both
devices are also available for operation over the standard temperature
range of -20°C to +85°C. To order, change the suffix letter ‘E’ to ‘S’.

ABSOLUTE MAXIMUM RATINGS

Supply Voltage, VDD...................... 7.0 V

Output Voltage Range,

V

O

............................ -0.5 V to +17 V

Output Current, I

O

........................ 90 mA

Ground Current, I

GND

................. 750 mA

Input Voltage Range,

V

I

.................... -0.4 V to VDD + 0.4 V

Package Power Dissipation,

P

D

..................................... See Graph

Operating Temperature Range,

TA............................. -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 suscep­tible to damage if exposed to extremely high
static electrical charges.

GROUND

REGISTER

LATCHES

1

2

3

89

10

11

12

13

15

4

5

6

7

14

16

SERIAL
DATA OUT

LOGIC
SUPPLY

SERIAL

DATA IN

OUTPUT
ENABLE

LATCH

ENABLE

CLOCK CK

V

DD

OE

OUT

1

OUT

2

Dwg. PP-029-10

OUT

0

OUT

4

OUT

6

OUT

5

OUT

3

OUT

7

R

EXT

I

REGULATOR

L

O

Note that the A6275EA (DIP) and the A6275ELW
(SOIC) are electrically identical and share a
common terminal number assignment.

6275

FEATURES

■ To 90 mA Constant-Current Outputs

■ Under-Voltage Lockout

■ Low-Power CMOS Logic and Latches

■ High Data Input Rate

■ Pin-Compatible with TB62705CP

115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]

6275

8-BIT SERIAL-INPUT,
CONSTANT-CURRENT
LATCHED LED DRIVER

2

Copyright © 2000, Allegro MicroSystems, Inc.

50 75 100 125 150

2.5

0.5

0

AMBIENT TEMPERATURE IN °C

2.0

1.5

1.0

25

Dwg. GP-018B

SUFFIX 'A', R = 60°C/W

θJA

SUFFIX 'LW', R = 80°C/W

θJA

ALLOWABLE PACKAGE POWER DISSIPATION IN WATTS

FUNCTIONAL BLOCK DIAGRAM

MOS

BIPOLAR

GROUND

LATCH

ENABLE

OUTPUT ENABLE
(ACTIVE LOW)

SERIAL
DATA OUT

CLOCK

SERIAL

DATA IN

SERIAL-PARALLEL SHIFT REGISTER

LATCHES

V

DD

LOGIC
SUPPLY

R

EXT

OUT0OUT

1

Dwg. FP-013-3

OUT

2

OUT

N

I

REGULATOR

O

UVLO

6275

8-BIT SERIAL-INPUT,

CONSTANT-CURRENT

LATCHED LED DRIVER

www.allegromicro.com

3

CLOCK and SERIAL DATA IN SERIAL DATA OUT

LATCH ENABLEOUTPUT ENABLE (active low)

Dwg. EP-010-6

IN

V

DD

Dwg. EP-010-7

IN

V

DD

Dwg. EP-010-5

IN

V

DD

Dwg. EP-063-1

V

DD

OUT

TRUTH TABLE

Serial Shift Register Contents Serial Latch Latch Contents Output Output Contents
Data Clock Data Enable Enable
Input Input I

1I2I3

... I

N-1IN

Output Input I1I2I3... I

N-1IN

Input I1I2I3... I

N-1

I

N

HHR

1R2

... R

N-2RN-1

R

N-1

LLR

1R2

... R

N-2RN-1

R

N-1

XR

1R2R3

... R

N-1RN

R

N

XXX...X X X L R1R2R3... R

N-1 RN

P1P2P3... P

N-1PN

P

N

HP1P2P3... P

N-1 PN

LP1P2P3... P

N-1 PN

XXX...X X H H H H ... H H

L = Low Logic (Voltage) Level H = High Logic (Voltage) Level X = Irrelevant P = Present State R = Previous State

115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]

6275

8-BIT SERIAL-INPUT,
CONSTANT-CURRENT
LATCHED LED DRIVER

4

ELECTRICAL CHARACTERISTICS at TA = +25°C, VDD = 5 V (unless otherwise noted).

Limits

Characteristic Symbol Test Conditions Min. Typ. Max. Unit

Supply Voltage Range V

DD

Operating 4.5 5.0 5.5 V

Under-Voltage Lockout V

DD(UV)

VDD = 0 → 5 V 3.4 – 4.0 V

Output Current I

O

VCE = 0.7 V, R

EXT

= 250 Ω 64.2 75.5 86.8 mA

(any single output)

VCE = 0.7 V, R

EXT

= 470 Ω 34.1 40.0 45.9 mA

Output Current Matching ∆I

O

0.4 V ≤ V

CE(A)

= V

CE(B)

≤ 0.7 V:

(difference between any R

EXT

= 250 Ω – ±1.5 ±6.0 %

two outputs at same VCE)

R

EXT

= 470 Ω – ±1.5 ±6.0 %

Output Leakage Current I

CEX

VOH = 15 V – 1.0 5.0 µA

Logic Input Voltage V

IH

0.7V

DD

–VDDV

V

IL

GND – 0.3V

DD

V

SERIAL DATA OUT V

OL

IOL = 500 µA––0.4V

Voltage

V

OH

IOH = -500 µ4A4.6––V

Input Resistance R

I

ENABLE Input, Pull Up 150 300 600 kΩ

LATCH Input, Pull Down 100 200 400 kΩ

Supply Current I

DD(OFF)

R

EXT

= open, VOE = 5 V – 0.8 1.4 mA

R

EXT

= 470 Ω, VOE = 5 V 3.5 6.0 8.0 mA

R

EXT

= 250 Ω, VOE = 5 V 6.5 11 15 mA

I

DD(ON)

R

EXT

= 470 Ω, VOE = 0 V 5.0 10 14 mA

R

EXT

= 250 Ω, VOE = 0 V 8.0 16 24 mA

Typical Data is at VDD = 5 V and is for design information only.