1/12
MSM6576
Semiconductor
GENERAL DESCRIPTION
MSM6576 is a 4-bit, low-power microcontroller that is manufactured in a CMOS silicon-gate
process. The microcontroller can be started and operated at a low supply voltage of 0.9 V.
This device contains a crystal oscillator circuit, voltage converter circuits, a time base counter,
a ROM, a RAM, a stack RAM, I/O ports, interrupt function components, a serial I/O port, a
buzzer output circuit, a level detector, and a differential amplifier.
This IC is driven by one battery and is well suited to products that need to be operated under
low power consumption.
FEATURES
The IC can be initialized and operated even at a low voltage of 0.9 V.
Low power consumption
ROM
: 2048 words 17 bits
RAM
: 64 words 4 bits
I/O port
Input-output port
: 7 ports 4 bits
Input port
: 1 port 1 bit
Interrupt functions (real-time interrupt, external interrupt, and serial interrupt)
Serial I/O port
: 8-bit sync communication
Buzzer output circuit
Level detector
: 7-level detection
Comparator
73 instructions
Minimum instruction execution time : 61 ms
Operation under single 1.5 V power supply
Built-in 32.768 kHz crystal oscillator circuit
Package options:
44-pin plastic QFP (QFP44-P-910-0.80-K)
(Product name : MSM6576-GS-K)
44-pin plastic QFP (QFP44-P-910-0.80-2K) (Product name : MSM6576-GS-2K)
Chip
indicates a code number.
Semiconductor
MSM6576
Operatable at 0.9 V and 7-level Detector 4-Bit Microcontroller
E2E0021-38-94
This version: Sep. 1998
Previous version: Mar. 1996
2/12
MSM6576
Semiconductor
BLOCK DIAGRAM
P7.3
P7.2
P7.1
P7.0
P6.3
P6.2
P6.1
P6.0
P5.3
P5.2
P5.1
P5.0
P4.3
P4.2
P4.1
P4.0
P3.3
P3.2
P3.1
P3.0
P2.3
P2.2
P2.1
P2.0
P1.3
P1.2
P1.1
P1.0
P0.3
P0.2
P0.1
P0.0
XT
XTB
PORT7
PORT6
PORT5
PORT4
PORT3
PORT2
PORT1
PORT0
OSC
TMOUT
TIME BASE
COUNTER
SYSTEM CLOCK
GENERATOR
LDIN
LEVEL DETECTOR
ADCON
ADSET
ADOUT
SIN
SOUT
SCKL
MODE
PCZIOX
PCHZX0
PCIOX0
PCHZ0
PCIO0
SCND0
SCND1
SERIAL I/O
SBFFL
SBFFH
D-BUS
EIF
EIRT
IRQRT
FIEX
IRQEX
PNEX
IRQSIO
PRIO
INTERRUPT CONTROL
RAM
64
4 bits
PAGE
WORK
ADRS
PROGRAM ROM
2048
17 bits
INSTRUCTION
REGISTER
INSTRUCTION
DECODER
STACK RAM
PROGRAM
COUNTER
ADDER
FRMT
FLAG
S-bus
ACC
A-bus
ALU
MPX
TEMPO
BUZZER
MDTH
MDTL
VOLTAGE
REGULATOR
BD
V
DD
V
SS1
V
SS2
V
EE
V
CP
V
CM
COMPARATOR
3/12
MSM6576
Semiconductor
PIN CONFIGURATION (TOP VIEW)
33
32
31
30
29
28
27
26
25
24
23
1
2
3
4
5
6
7
8
9
10
11
P4.1
P4.2
P4.3
RESET
TEST1
TEST2
TEST3
P5.0
P5.1
P5.2
P5.3
P1.1
P1.0
P0.3
P0.2
P0.1
P0.0
BD
P7.0/SIN
P7.1 (LDIN)
P7.2 (OPIN2)
P7.3 (OPIN1)
44
43
42
41
40
39
38
37
36
35
34
P4.0
P3.3
P3.2
P3.1
P3.0
V
DD
P2.2
P2.1
P2.0
P1.3
P1.2
12
13
14
15
16
17
18
19
20
21
22
P6.0
P6.2/
SCLK
P6.3/SOUT
XTB
XT
V
DD
V
SS1
V
CM
V
CP
V
SS2
V
EE
44-Pin Plastic QFP
Notes: 1. P6.3, P7.0 and P7.1 are used as serial port pins as well.
P7.2 and P7.3 are used as up/down counter pins as well.
2. P6.1 is not assigned as a pin.
4/12
MSM6576
Semiconductor
PIN DESCRIPTIONS
Symbol
Type
Description
PORT0
(P0.0 to P0.3)
I/O
4-bit input-output port, I/O switchable, input pull-down resistor/pull-up resistor
switchable, with/without input resistor
I/O
4-bit input-output port, I/O switchable, with/without input pull-down resistor
I/O
4-bit input-output port, I/O switchable,
with/without input pull-down resistor
I/O
4-bit input-output port, I/O switchable, with/without input pull-down resistor
I/O
4-bit input-output port, I/O switchable, with/without input pull-down resistor
I/O
4-bit input-output port, I/O switchable, with/without input pull-down resistor
I/O
4-bit input-output port, I/O switchable,
with/without input pull-down resistor
P7.0: Input port, without input resistor
BD
O
Buzzer output pin
RESET
I
Reset pin with input pull-down resistor
TEST1
Testing pins with input pull-down resistor
Tie to the negative pole of the battery.
TEST2
I
TEST3
XT
I
Connection pins for crystal
XTB
O
V
DD
--
0 V power supply pin
V
SS1
--
1.5 V supply pin (power supply pin for 1.5 V operation)
V
SS2
--
3.0 V supply pin (power supply pin for 3.0 V operation)
V
CP
--
Connection pins for internal potential development capacitor
V
CM
PORT1
(P1.1 to P1.3)
PORT2
(P2.0 to P2.3)
PORT3
(P3.0 to P3.3)
PORT4
(P4.0 to P4.3)
PORT5
(P5.0 to P5.3)
PORT6
(P6.0 to P6.3)
P2.0 to P2.3
External interrupt
port
P6.3: SOUT
Shared with serial
port
I
PORT7
(P7.0 to P7.3)
V
EE
--
Supply pin for internal logic (constant voltage circuit output pin)
P6.2: SCLK
P7.1: Input pin for level detector
P7.2: Input pin for comparator
P7.3: Input pin for comparator
P7.0: SIN
5/12
MSM6576
Semiconductor
ABSOLUTE MAXIMUM RATINGS
1.5 V operation
Backup flag (BUF) = "0"
The input of the constant voltage circuit is equal to the output of the voltage converter (V
SS2
).
Parameter
Symbol
Condition
Range
Unit
Operating Voltage
V
op
--
3.5 to 0.9
V
V
--
Operating Temperature
T
op
20 to +70
C
--
Oscillation Frequency
f
OSC
32.768
kHz
--
V
DD
= 0 V (V
SS1
= battery voltage)
Parameter
Symbol
Condition
Rating
Unit
Power Supply Voltage
V
SS1
Ta = 25C
6.0 to +0.3
Input Voltage
V
IN
V
SS1
0.3 to +0.3
V
Output Voltage
V
OUT
V
SS1
0.3 to +0.3
Storage Temperature
T
STG
--
55 to +150
C
V
DD
= 0 V (V
SS1
= battery voltage)
RECOMMENDED OPERATING CONDITIONS
1.5 V operation
Backup flag (BUF) = "0"
The input of the constant voltage circuit is equal to the output of the voltage converter (V
SS2
).
6/12
MSM6576
Semiconductor
ELECTRICAL CHARACTERISTICS
1.5 V operation
Backup flag (BUF) = "0"
The input of the constant voltage circuit is equal to the output of the voltage converter (V
SS2
).
*1 Depends on program. (Values in the above table are applied in the case where the software
duty is about 3%.)
*2 PORT0 = P0.0 to P0.3, PORT1 = P1.0 to P1.3, PORT2 = P2.0 to P2.3, PORT3 = P3.0 to P3.3,
PORT4 = P4.0 to P4.3, PORT5 = P5.0 to P5.3, PORT6 = P6.0 to P6.3, PORT7 = P7.0 to P7.3
Parameter
Symbol
Condition
Min.
Applied Pin
Typ. Max. Unit
Power Supply Current 1 *1
I
DD1
Level detector OFF
--
--
3
--
mA
Power Supply Current 2 *1
I
DD2
Level detector ON
--
--
15
--
mA
V
OSC
Within 2 seconds
--
V
SS1
--
0.9
I
OH1
V
O
= 0.5 V
150
--
--
I
OL1
V
O
= 1.0 V
150
--
--
V
O
= 0.5 V
20
--
--
V
O
= 1.0 V
BD
(V
DD
= 0 V, V
SS1
= 1.5 V (battery voltage) , V
SS2
= 3.0 V, f
OSC
= 32.768 kHz, C
X
= 35 pF, Ta = 25C)
Oscillation Start Voltage
Output Current 1
Output Current 2
Input Current 1
Input Current 2
Input Leakage Current
V
mA
mA
mA
mA
PORT0 to PORT6*2
SOUT, SCLK
I
OH2
I
OL2
20
--
--
V
I
= 0 V, in the input state,
with pull-down resistor
I
IH1
3.75
7.5
15
I
IH2
3.75
7.5
15
I
IL
--
--
1
PORT0 to
PORT6 *2
V
I
= 1.5 V, in the input state,
with pull-up resistor
PORT0
V
I
= 0 V, 1.5 V, in the input
state, without pull-down resistor
mA
PORT0 to PORT7*2
SIN, SOUT, SCLK
Input Current 3
mA
I
IH3
70
250
500
V
I
= 0 V, with pull-down
resistor
RESET, TEST1
to TEST3
Input Voltage
V
IH
--
--
0.3
--
All input pins
V
V
IL
1.2
--
--
Level Detector Off Voltage
mV
V
LD
off
0
--
80
ADSTART = "0"
P7.1
Level Detector Detecting
Voltage
V
LD
6
H
725
742
759
(ADOUT) = 6
H
V
LD
5
H
841
858
875
(ADOUT) = 5
H
V
LD
4
H
958
975
992
(ADOUT) = 4
H
V
LD
3
H
1075 1092 1109
(ADOUT) = 3
H
V
LD
2
H
1191 1208 1225
(ADOUT) = 2
H
V
LD
1
H
1308 1325 1342
(ADOUT) = 1
H
V
LD
0
H
1425 1442 1459
(ADOUT) = 0
H
Level Detector Settling Time
ms
t
SET
--
--
61
ADSTART = "1", during
OUT ADSET execution
Level Detector Conversion Rate
Hz
f
LD
--
--
100
--
Comparator Offset Voltage
mV
V
CMP
off
--
--
15
--
P7.3, P7.2
Comparator Input Voltage
V
V
CMP
in
V
B
/2
--
V
B
V
B
= Battery voltage
Comparator Conversion Rate
Hz
f
CMP
--
--
100
--
mV
--
7/12
MSM6576
Semiconductor
ABSOLUTE MAXIMUM RATINGS
1.5 V operation
Backup flag (BUF) = "1"
The input of the constant voltage circuit is directly connected to the power supply (V
SS1
).
Parameter
Symbol
Condition
Rating
Unit
Power Supply Voltage
V
SS1
Ta = 25C
6.0 to +0.3
Input Voltage
V
IN
V
SS1
0.3 to +0.3
V
Output Voltage
V
OUT
V
SS1
0.3 to +0.3
Storage Temperature
T
STG
--
55 to +150
C
V
DD
= 0 V (V
SS1
= battery voltage)
RECOMMENDED OPERATING CONDITIONS
1.5 V operation
Backup flag (BUF) = "1"
The input of the constant voltage circuit is directly connected to the power supply (V
SS1
).
Parameter
Symbol
Condition
Range
Unit
Operating Voltage
V
op
--
3.5 to 0.9
V
V
--
Operating Temperature
T
op
20 to +70
C
--
Oscillation Frequency
f
OSC
32.768
kHz
--
V
DD
= 0 V (V
SS1
= battery voltage)
8/12
MSM6576
Semiconductor
ELECTRICAL CHARACTERISTICS
1.5 V operation
Backup flag (BUF) = "1"
The input of the constant voltage circuit is directly connected to the power supply (V
SS1
).
Parameter
Symbol
Condition
Min.
Applied Pin
Typ. Max. Unit
Power Supply Current 1 *1
I
DD1
Level detector OFF
--
--
1.5
--
mA
Power Supply Current 2 *1
I
DD2
Level detector ON
--
--
13.5
--
mA
V
OSC
Within 2 seconds
--
V
SS1
--
0.9
I
OH1
V
O
= 0.5 V
150
--
--
I
OL1
V
O
= 1.0 V
150
--
--
V
O
= 0.5 V
20
--
--
V
O
= 1.0 V
BD
(V
DD
= 0 V, V
SS1
= 1.5 V (battery voltage) , V
SS2
= 3.0 V, f
OSC
= 32.768 kHz, C
X
= 35 pF, Ta = 25C)
Oscillation Start Voltage
Output Current 1
Output Current 2
Input Current 1
Input Current 2
Input Leakage Current
V
mA
mA
mA
mA
PORT0 to PORT6*2
SOUT, SCLK
I
OH2
I
OL2
20
--
--
V
I
= 0 V, in the input state,
with pull-down resistor
I
IH1
3.75
7.5
15
I
IH2
3.75
7.5
15
I
IL
--
--
1
PORT0 to
PORT6 *2
V
I
= 1.5 V, in the input state,
with pull-up resistor
PORT0
V
I
= 0 V, 1.5 V, in the input
state, without pull-down resistor
mA
PORT0 to PORT7*2
SIN, SOUT, SCLK
Input Current 3
mA
I
IH3
70
250
500
V
I
= 0 V, with pull-down
resistor
RESET, TEST1
to TEST3
Input Voltage
V
IH
--
--
0.3
--
All input pins
V
V
IL
1.2
--
--
Level Detector Off Voltage
mV
V
LD
off
0
--
80
ADSTART = "0"
P7.1
Level Detector Detecting
Voltage
V
LD
6
H
725
742
759
(ADOUT) = 6
H
V
LD
5
H
841
858
875
(ADOUT) = 5
H
V
LD
4
H
958
975
992
(ADOUT) = 4
H
V
LD
3
H
1075 1092 1109
(ADOUT) = 3
H
V
LD
2
H
1191 1208 1225
(ADOUT) = 2
H
V
LD
1
H
1308 1325 1342
(ADOUT) = 1
H
V
LD
0
H
1425 1442 1459
(ADOUT) = 0
H
Level Detector Settling Time
ms
t
SET
--
--
61
ADSTART = "1", during
OUT ADSET execution
Level Detector Conversion Rate
Hz
f
LD
--
--
100
--
Comparator Offset Voltage
mV
V
CMP
off
--
--
15
--
P7.3, P7.2
Comparator Input Voltage
V
V
CMP
in
V
B
/2
--
V
B
V
B
= Battery voltage
Comparator Conversion Rate
Hz
f
CMP
--
--
100
--
mV
--
*1 Depends on program. (Values in the above table are applied in the case where the software
duty is about 3%.)
*2 PORT0 = P0.0 to P0.3, PORT1 = P1.0 to P1.3, PORT2 = P2.0 to P2.3, PORT3 = P3.0 to P3.3,
PORT4 = P4.0 to P4.3, PORT5 = P5.0 to P5.3, PORT6 = P6.0 to P6.3, PORT7 = P7.0 to P7.3
9/12
MSM6576
Semiconductor
NOTES ON USE
Power Supply for 0.9 V Microcontroller Series (Backup Flag and Constant-Voltage Circuit)
The 0.9 V microcontroller series has built-in constant-voltage circuit. The output of this
constant-voltage circuit powers the microcontroller's internal logic circuits. Setting a backup
flag (BUF) allows the input of the constant-voltage circuit to be switched to either the battery
or the output generated in the voltage converter, based on the battery voltage. A battery voltage
is 1.5 V.
The output (V
EE
) of the constant-voltage circuit is set at approximately 1.3 V. This allows the
current consumed by the internal logic to be limited, irrespective of the battery voltage.
However, if the input of the constant-voltage circuit is below this set value (about 1.3 V), the
output (V
EE
) is equal to the input. The 0.9 V microcontroller can be operated even if the internal
voltage (output from the constant-voltage circuit) falls to 0.9 V. Setting the backup flag allows
a larger operating voltage margin despite changes in internal voltage due to noise. For example,
for the 1.5 V operation, setting the backup flag to "0" supplies twice the battery voltage to the
constant-voltage circuit. Thus, even if the battery voltage falls to 0.9 V, the output voltage (V
EE
)
is maintained at 1.3 V, providing a larger margin of operating voltage of the internal logic
circuits because 1.8 V is applied to the input of the constant-voltage circuit. Figures 1 and 2 show
the internal status depending on the backup flag settings for the battery, as well as status
features.
XTAL
V
DD
(0 V)
V
SS1
(1.5 V)
V
SS2
(3.0 V)
V
SS3
*
(4.5 V)
V
EE
(About1.3 V)
LCD driver*
Voltage
converter
Backup flag
(BUF)
Constant-voltage circuit
VR
Internal
logic
XT
XTB
*The V
SS3
pin is provided for the devices that contain an
LCD driver.
10/12
MSM6576
Semiconductor
(Figure 1) 1.5 V Operation (Backup Flag = "1")
(Figure 2) 1.5 V Operation (Backup Flag = "0")
Voltage converter
VR
Internal logic
V
DD
= 0 V
V
B
= 1.5 V
(3.0 V)
V
EE
V
DD
V
SS1
V
SS2
Voltage
doubler
Internal
status
Operating
range
Current
consumption
Feature
A doubled level of V
SS2
is applied to the input of the
constant-voltage circuit. (V
SS2
).
0.9 to 3.5 V
3 mA*
When the baftery level is powered down, a larger
operating voltage margin is gained, compared to the
case of Figure 1.
* When the software duty is about 5%
Voltage converter
VR
Internal logic
V
DD
= 0 V
V
B
= 1.5 V
(3.0 V)
V
EE
V
DD
V
SS1
V
SS2
Voltage
doubler
Internal
status
Operating
range
Current
consumption
Feature
The battery level V
SS1
is applied to the input of the
constant-voltage circuit. (V
SS2
).
0.9 to 3.5 V
1.5 mA*
When the battery level is powered down, the internal
circuit is powered directly by the battery.
* When the software duty is about 5%
11/12
MSM6576
Semiconductor
(Unit : mm)
PACKAGE DIMENSIONS
Notes for Mounting the Surface Mount Type Package
The SOP, QFP, TSOP, SOJ, QFJ (PLCC), SHP and BGA are surface mount type packages, which
are very susceptible to heat in reflow mounting and humidity absorbed in storage.
Therefore, before you perform reflow mounting, contact Oki's responsible sales person for the
product name, package name, pin number, package code and desired mounting conditions
(reflow method, temperature and times).
QFP44-P-910-0.80-K
Package material
Lead frame material
Pin treatment
Solder plate thickness
Package weight (g)
Epoxy resin
42 alloy
Solder plating
5 mm or more
0.35 TYP.
Mirror finish
12/12
MSM6576
Semiconductor
(Unit : mm)
Notes for Mounting the Surface Mount Type Package
The SOP, QFP, TSOP, SOJ, QFJ (PLCC), SHP and BGA are surface mount type packages, which
are very susceptible to heat in reflow mounting and humidity absorbed in storage.
Therefore, before you perform reflow mounting, contact Oki's responsible sales person for the
product name, package name, pin number, package code and desired mounting conditions
(reflow method, temperature and times).
Package material
Lead frame material
Pin treatment
Solder plate thickness
Package weight (g)
Epoxy resin
42 alloy
Solder plating
5 mm or more
0.41 TYP.
QFP44-P-910-0.80-2K
Mirror finish
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