MITMSITUSBUISBHISI HDIIGDIITGAILTAALSASSPSP
M66503MA66S50P3A/ASPG/APGP
16-BIT CONSTANT CURRENT LED DRIVER with SHIFT REGISTER AND LATCH
16-BIT CONSTANT CURRENT LED DRIVER with SHIFT REGISTER AND LATCH
DESCRIPTION
PIN CONFIGURATION (TOP VIEW)
The M66503A is a constant current LED driver IC, whose
output current is variable. The IC’s functions include 16-bit
serial input/parallel output shift register with output latch.
The product uses Bi-CMOS process for highly accurate con-
stant current driving, permitting high-efficiency LED driving
without using a resistor that limits LED current.
Settings for the LED drive current are made by an external re-
sister, thereby ensuring a maximum output current of 30 mA,
enough for anode-common LED driving.
1
2
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
GND1
VCC
SERIAL DATA INPUT
A
RC CURRENT SETTING INPUT
SQ15 SERIAL DATA OUTPUT
3
SHIFT CLOCK INPUT CK
S
LATCH ENABLE LE
INPUT NC
4
OE
A
B
OUTPUT ENABLE INPUT A
OUTPUT ENABLE INPUT B
5
OE
6
Q
Q
0
1
Q
Q
15
14
PARALLEL DATA
OUTPUT
PARALLEL DATA
OUTPUT
Furthermore, the pin configuration of the IC permits easier
wiring on a printed board.
7
8
GND2
GND5
9
Q
Q
Q
Q
2
3
4
5
Q
Q
Q
Q
13
12
11
10
FEATURES
• Anode-common LED driving
10
11
12
13
14
15
PARALLEL DATA
OUTPUT
PARALLEL DATA
OUTPUT
• Constant current output: Set to a value within a range be-
tween 0 and 30mA with an external resistor only.
Simultaneous lighting available.
• Pins (OEA, OEB) provided for forced ON/OFF of LED drive
current.
• Greater noise margin: Total-input Schmitt circuit is em-
ployed to deal with longer wire lengths.
• Input/output CMOS compatible
GND3
GND4
Q
Q
6
7
Q
Q
9
8
PARALLEL DATA
OUTPUT
PARALLEL DATA
OUTPUT
Outline 30P4B
• Serial data output provided (SQ15)
• 5V single power supply
• Pin configuration for easier wiring on printed board
GND1
1
2
36
35
34
33
32
31
30
29
28
27
VCC
CURRENT SETTING INPUT
SERIAL DATA INPUT
A
RC
SERIAL DATA OUTPUT
SHIFT CLOCK INPUT CK
S
3
SQ15
APPLICATION
LED array drivers for display panel and printer. Other various
LED modules.
OUTPUT ENABLE INPUT A
OUTPUT ENABLE INPUT B
LE
4
OE
OE
NC
A
B
LATCH ENABLE
INPUT NC
5
NC
6
Q
Q
Q
Q
0
1
2
3
7
Q
Q
Q
Q
15
14
FUNCTION
8
PARALLEL DATA
OUTPUT
PARALLEL DATA
OUTPUT
The M66503A is a constant current LED driver for anode-
common LEDs. To set the LED driving current, an external
resistor is connected between the current setting input pin,
RC, and GND. In this way it is possible to set a highly accu-
rate drive current. Each bit of the shift register is made up of a
flip-flop performing shift function and a latch connected to the
output. When the clock input pin, CKS, goes from “L” to “H”,
data is shifted. Serial data is entered to the shift register via
the serial data input pin, A. Data on A is straight shifted. By
turning the latch enable input pin, LE, to “L”, the contents
stored in the shift register is latched. All outputs are turned off
if the output enable input pins, OEA and OEB, are simulta-
neously set to “L”. This function is useful for the prevention of
an excessive current flowing at the moment of power on. All
outputs are turned on if the OEA pin is set to “H”. This enables
to check LEDs for failure. In these actions, changing the state
of OEA and/or OEB does not affect the shift function. To ex-
pand the number of bits, link the M66503A in serial using the
serial data output pin, SQ15, which is the serial data output
of the shift register.
9
13
12
10
GND2 11
26 GND3
Q
Q
4
5
12
13
25
24
Q
Q
11
10
PARALLEL DATA
OUTPUT
PARALLEL DATA
OUTPUT
NC 14
NC 15
NC 16
23 NC
22 NC
21 NC
Q
Q
6
7
17
18
20
19
Q
Q
9
8
PARALLEL DATA
OUTPUT
PARALLEL DATA
OUTPUT
Outline 36P2R-D
NC: No Connection
1