SM1125 series
SEIKO NPC CORPORATION —1
Multimelody IC for Pagers
OVERVIEW
The SM1125 series are melody ICs fabricated in NPC’s Molybdenum-gate CMOS for use in mobile telecom-
munications equipment. A maximum of 16 melodies can be stored in programmable ROM.
FEATURES
■
Maximum of 16 melody selections (with up to 512
steps)
■
Level hold playback mode
■
External reference clock input versions and built-
in RC oscillator versions available, set by master-
slice option (RC oscillator versions require an
external resistor and capacitor).
■
12 selectable clock frequencies (fixed for all melo-
dies)
• External clock input versions (12 frequencies)
- 32.768kHz system: 32.768, 65.536 and
131.072kHz
- 37.5kHz system: 37.5, 75.0 and 150.0kHz
- 38.4kHz system: 38.4, 76.8 and 153.6kHz
- 48.0kHz system: 48.0, 96.0 and 192.0kHz
• Built-in oscillator versions (4 frequencies)
- 38.4kHz (standard oscillator frequency)
- 32.768kHz
- 37.5kHz
- 48.0kHz
■
2-pin serial data melody selection and 1-pin mel-
ody playback control
■
Power save function
• External clock input versions
Clock gating in no-play modes
• Built-in RC oscillator versions
Oscillator stopped in no-play modes
■
Molybdenum-gate CMOS process
■
8-pin plastic VSOP package
ORDERING INFORMATION
PINOUT
(Top view)
PACKAGE DIMENSIONS
(Unit: mm)
Device Package
SM1125
××
V 8pin VSOP
OSC
SI
SC
ST
VSS
VDD
MTO
TEST
1
45
6
2
3
7
8
4.4 ± 0.2
6.4 ± 0.3
0.65
0.22 ± 0.1
1.15 ± 0.05
0.5 ± 0.2
0.575 TYP
0.15 + 0.1
− 0.05
0.12
+M
0.10
0.1 ± 0.05
3.1 ± 0.3
SM1125 series
SEIKO NPC CORPORATION —2
BLOCK DIAGRAM
PIN DESCRIPTION
Number Name I/O Function
1 OSC I Built-in RC oscillator option: External resistor and capacitor connection pins
External clock input option: External reference clock input (gate circuit built-in)
2 SI I Playback control serial interface data input
3 SC I Playback control serial interface clock input
4 ST I Playback start/stop control signal input
5 TEST I Test input pin. Leave open or tie to VSS. (Pull-down resistance built-in)
6 MTO O Playback melody signal output
7 VDD – Supply pin (+)
8 VSS – Ground pin
Gate
1/2 or 1/4 SW2
Divider
1/128
Scale
Counter
Scale
ROM
Tempo Latch
Tempo Counter
Rhythm
Counter Address
Counter
Start
Address
Latch
Main
ROM
Control
Circuit
OSC
SI
SC
ST
VSS
VDD
MTO
TEST
Multi-
Plexer
OSC
SW1
Master slice
SM1125 series
SEIKO NPC CORPORATION —3
SPECIFICATIONS
Absolute Maximum Ratings
Recommended Operating Conditions
V
SS
= 0V
DC Characteristics
Unless otherwise noted Ta =
−
20 to 70
°
C, V
SS
= 0V, V
DD
= 1.5 to 3.6V
Parameter Symbol Condition Rating Unit
Supply voltage range V
DD
−
V
SS
−
0.3 to 5.0 V
Input voltage range V
IN
V
SS
−
0.2 to V
DD
+ 0.2 V
Power dissipation P
D
100 mW
Storage temperature range T
stg
−
40 to 125
°
C
Parameter Symbol Condition Rating Unit
Supply voltage V
DD
2.0 to 3.6 V
Operating temperature T
opr
−
20 to 70
°
C
Parameter Symbol Condition
Rating
Unit
min typ max
Supply voltage (1) V
DD1
External clock input option 1.5 3.0 3.6 V
Supply voltage (2) V
DD2
Built-in RC oscillator option 2.0 3.0 3.6 V
Current consumption (1) I
DD1
Non-playback mode, Ta = 25
°
C – – 0.5 µA
Current consumption (2) I
DD2
External clock input option: Playback mode,
MTO pin open – 25 200 µA
Current consumption (3) I
DD3
Built-in RC oscillator option: Playback mode,
MTO pin open – 215 600 µA
Input voltage
V
IH
ST, SI, SC and OSC (External clock input
option) pins
V
DD
−
0.2 – V
DD
V
V
IL
V
SS
–V
SS
+ 0.2 V
Input current (1)
I
IH1
ST, SI, SC and OSC (External clock input
option) pins, V
IH
= V
DD
, Ta = 25
°
C– – 0.5 µA
I
IL1
ST, SI, SC and OSC (External clock input
option) pins, V
IL
= 0 V, Ta = 25
°
C– – 0.5 µA
Input current (2) I
IH2
TEST pin, V
IH
= V
DD
– – 200 µA
Open voltage V
OPN
TEST pin – – 0.1 V
Output voltage
V
OH
MTO pin, I
OH
= 1mA V
DD
−
0.4 – V
DD
V
V
OL
MTO pin, I
OL
= 1mA V
SS
–V
SS
+ 0.4 V
Oscillator frequency f
OSC
Built-in RC oscillator option: NPC test board
measurement, R
O
= 91k
Ω
, C
O
= 200pF
V
DD
= 2.0 to 3.6V
34.5 38.4 42.5 kHz
Frequency stability
∆
f/f Built-in RC oscillator option – 0.1 – %/0.1V
Oscillator start voltage V
DOB
Built-in RC oscillator option – – 1.6 V
Oscillator stop voltage V
DOS
Built-in RC oscillator option – – 1.6 V
SM1125 series
SEIKO NPC CORPORATION —4
AC Characteristics
Unless otherwise noted Ta =
−
20 to 70
°
C, V
SS
= 0V, V
DD
= 1.5 to 3.6V
OSC input pulse (External clock input option)
SC input pulse
SC-SI serial input pulse
Parameter Symbol Condition
Rating
Unit
min typ max
OSC pulse cycle t
OSC
“OSC input pulse (External clock
input option)” timing
5.0 – – µs
OSC HIGH-level pulsewidth t
OWH
2.0 – – µs
OSC LOW-level pulsewidth t
OWL
2.0 – – µs
OSC pulse rise time t
Or
– – 200 ns
OSC pulse fall time t
Of
– – 200 ns
SC pulse cycle t
SC
“SC input pulse” timing
5.0 – – µs
SC HIGH-level pulsewidth t
SWH
2.0 – – µs
SC LOW-level pulsewidth t
SWL
2.0 – – µs
SC pulse rise time t
Sr
– – 200 ns
SC pulse fall time t
Sf
– – 200 ns
SI-SC setup time t
DS
“SC-SI serial input pulse” timing
2.0 – – µs
SI-SC hold time t
DH
2.0 – – µs
V
IH
V
IL
0.5V
DD
t
Of
t
Or
t
OSC
t
0.1VDD
0.9VDD
OWLOWH
t
V
IH
V
IL
0.5V
DD
t
Sf
t
Sr
SWL
t
SC
t
0.1VDD
0.9VDD
t
SWH
V
IH
V
IL
0.5V
DD
SC
V
IH
V
IL
0.5V
DD
SI
DH
tt
DS
SM1125 series
SEIKO NPC CORPORATION —5
FUNCTIONAL DESCRIPTION
Control Functions
Reference clock
SM1125 series devices are available in external clock input versions and built-in RC oscillator versions, set by
master-slice option. In the case of the built-in RC oscillator option, an external resistor and capacitor is
required for the oscillator function.
SM1125 series can operate at 12 selectable reference clock frequencies. All melodies playback at the fixed
speed set by the reference clock frequency. External clock input versions operate at one of 12 selectable clock
frequencies, as shown in table 1. Built-in RC oscillator versions operate at one of 4 selectable oscillator fre-
quencies—32.768kHz, 37.5kHz, 38.4kHz (standard frequency) and 48.0kHz.
In external clock input versions, the external reference clock input is used during playback mode only and is
otherwise ignored. If a clock signal is input when not in playback mode (when ST is LOW), the gate circuit
switches to cutoff the external reference clock signal from entering the device, preventing unwanted current
flow.
In built-in RC oscillator versions, the oscillator is stopped when not in playback mode (when ST is LOW), pre-
venting unwanted current flow.
Table 1. Reference clock frequencies
Frequency
system Selectable frequencies
32.768kHz 32.768kHz 65.536kHz 131.072kHz
37.5kHz 37.5kHz 75.0kHz 150.0kHz
38.4kHz 38.4kHz 76.8kHz 153.6kHz
48.0kHz 48.0kHz 96.0kHz 192.0kHz
Figure 1. External clock input version: Input during playback mode only
Figure 2. External clock input version: Input during non-playback mode
Figure 3. Built-in RC oscillator version
ST
OSC
ST
OSC
ST
OSC CR
Oscillator
SM1125 series
SEIKO NPC CORPORATION —6
Playback control
The ST pin controls the start of playback. While ST is HIGH, the melody is played repeatedly, and when ST
goes LOW, playback stops. Melodies are selected by input serial data on pins SI and SC, as shown in table 2.
The final 4 serial data bits in any input data string form the valid selection data, and this data is retained even
after playback. If serial data is input during playback, the data is ignored and playback continues.
Serial data selection
Pin SC should be LOW when either a LOW-to-HIGH or HIGH-to-LOW transition occurs on pin ST.
Figure 4. Serial data input timing
Table 2. Serial data melody select
B3 B2 B1 B0 ST Melody B3 B2 B1 B0 ST Melody
LLLLL
→
H 1st melody H L L L L
→
H 9th melody
LLLHL
→
H 2nd melody H L L H L
→
H 10th melody
LLHLL
→
H 3rd melody HLHLL
→
H 11th melody
LLHHL
→
H 4th melody H L H H L
→
H 12th melody
LHLLL
→
H 5th melody H H L L L
→
H 13th melody
LHLHL
→
H 6th melody H H L H L
→
H 14th melody
LHHLL
→
H 7th melody H H H L L
→
H 15th melody
LHHHL
→
H 8th melody HHHHL
→
H 16th melody
Melody plays repeatedly when ST is HIGH, and stops immediately when ST goes LOW.
Figure 5. Melody repetition timing
SI
SC
ST
MTO
??
B3 B2 B1 B0 ????
Invalid
Data
Valid
Data
Invalid
Data
SI
SC
ST
MTO
#n1 Data #n2 Data
#n1 Play #n1 Play #n1 Play #n2 Play
SM1125 series
SEIKO NPC CORPORATION —7
Playback timing diagrams
Playback start
Playback starts 128 ± 1 OSC clock cycles after ST goes HIGH.
Playback stop
Playback stops immediately when ST goes LOW.
In external clock input versions, the IC internal clock also stops when ST goes LOW, regardless of whether or
not there is a clock input signal on pin OSC.
In built-in RC oscillator versions, the oscillator also stops when ST goes LOW.
Figure 6. Start timing
Figure 7. Stop timing
;;;;;;
;;;;;;
SI
SC
ST
MTO
MSB LSB
Invalid
Data
Valid
Data
CLK
*Internal
Clock
128 1 Clock
;;;;;;;;;;;;;;;;;
;
;;;;;;;;;;;;;;;
;
;;;;;;;;;;;;;;;;;
ST
MTO
CLK
*Internal
Clock
SM1125 series
SEIKO NPC CORPORATION —8
Musical Specifications
Maximum program steps
The mask for the built-in ROM can be programmed with up to a maximum of 512 steps, where each step repre-
sents either a note (sound pitch and length) or a rest.
Note length (including rests)
Eight rhythm values for notes and rests can be programmed. Also, 2 or more notes can be musically tied.
Pitch and scale
SM1125 series devices perform uniform interval length processing to reduce the error at high pitches. This
maintains the relative phase when the frequency varies from the input value.
The pitch varies with the clock frequency, as shown in the frequency listing in table 4.
The frequency variation from the input frequency is the sum of the relative error, shown in the frequency table,
plus the pitch error.
(Ex) 38.4kHz system, A4 note
Relative error: 8.99 cent
Pitch error:
−3.58 cent
Total: +5.41 cent
Error calculation:
Table 3. Rhythm values
01234567
Note
Rest
1200 × log2= 1200 ×
Reference frequency
Output frequency log10 Reference frequency
Output frequency
log102
≈ 3986.3 × log10 Reference frequency
Output frequency
≈ 3986.3 × log10 440.000
441.379
≈ 5.41 cent
SM1125 series
SEIKO NPC CORPORATION —9
(Note) A4 is the following note.
Table 4. Frequency range
Number Frequency
divider
Relative
error
[cent]
32.768kHz system 37.5kHz system 38.4kHz system 48kHz system
Pitch Frequency
[Hz] Pitch Frequency
[Hz] Pitch Frequency
[Hz] Pitch Frequency
[Hz]
1 247 2.49 C3 132.664 D#3 151.822 D#3 155.466 G3 194.332
2 233 3.50 C#3 140.635 E3 160.944 E3 164.807 G#3 206.009
3 220 2.89 D3 148.945 F3 170.455 F3 174.545 A3 218.182
4 208 0.00 D#3 157.538 F#3 180.288 F#3 184.615 A#3 230.769
5 196 2.88 E3 167.184 G3 191.327 G3 195.918 B3 244.898
6 185 2.87 F3 177.124 G#3 202.703 G#3 207.568 C4 259.459
7 175 −0.93 F#3 187.246 A3 214.286 A3 219.429 C#4 274.286
8 165 0.94 G3 198.594 A#3 227.273 A#3 232.727 D4 290.909
9 156 −1.96 G#3 210.051 B3 240.385 B3 246.154 D#4 307.692
10 147 0.93 A3 222.912 C4 255.102 C4 261.224 E4 326.531
11 139 −2.21 A#3 235.741 C#4 269.784 C#4 276.259 F4 345.324
12 131 0.42 B3 250.137 D4 286.260 D4 293.130 F#4 366.412
13 124 −4.50 C4 264.258 D#4 302.419 D#4 309.677 G4 387.097
14 117 −3.91 C#4 280.068 E4 320.513 E4 328.205 G#4 410.256
15 110 2.89 D4 297.891 F4 340.909 F4 349.091 A4 436.364
16 104 0.00 D#4 315.077 F#4 360.577 F#4 369.231 A#4 461.538
17 98 2.88 E4 334.367 G4 382.653 G4 391.837 B4 489.796
18 93 −6.46 F4 352.344 G#4 403.226 G#4 412.903 C5 516.129
19 87 8.99 F#4 376.644 A4 431.034 A4 441.379 C#5 551.724
20 83 −9.52 G4 394.795 A#4 451.807 A#4 462.651 D5 578.313
21 78 −1.96 G#4 420.103 B4 480.769 B4 492.308 D#5 615.385
22 74 −10.81 A4 442.811 C5 506.757 C5 518.919 E5 648.649
23 69 10.29 A#4 474.899 C#5 543.478 C#5 556.522 F5 695.652
24 66 −12.74 B4 496.485 D5 568.182 D5 581.818 F#5 727.273
25 62 −4.50 C5 528.516 D#5 604.839 D#5 619.355 G5 774.194
26 58 10.95 C#5 564.966 E5 646.552 E5 662.069 G#5 827.586
27 55 2.89 D5 595.782 F5 681.818 F5 698.182 A5 872.727
28 52 0.00 D#5 630.154 F#5 721.154 F#5 738.462 A#5 923.077
29 49 2.88 E5 668.735 G5 765.306 G5 783.673 B5 979.592
30 46 12.26 F5 712.348 G#5 815.217 G#5 834.783 C6 1043.478
31 44 −10.79 F#5 744.727 A5 852.273 A5 872.727 C#6 1090.909
32 41 11.47 G5 799.220 A#5 914.634 A#5 936.585 D6 1170.732
33 39 −1.96 G#5 840.205 B5 961.538 B5 984.615 D#6 1230.769
34 37 −10.81 A5 885.622 C6 1013.514 C6 1037.838 E6 1297.297
35 35 −14.62 A#5 936.229 C#6 1071.429 C#6 1097.143 F6 1371.429
36 33 −12.74 B5 992.970 D6 1136.364 D6 1163.636 F#6 1454.545
37 31 −4.50 C6 1057.032 D#6 1209.677 D#6 1238.710 G6 1548.387
38 29 10.95 C#6 1129.931 E6 1293.103 E6 1324.138 G#6 1655.172
39 28 −28.30 D6 1170.286 F6 1339.286 F6 1371.429 A6 1714.286
40 26 0.00 D#6 1260.308 F#6 1442.308 F#6 1476.923 A#6 1846.154
41 25 −32.09 E6 1310.720 G6 1500.000 G6 1536.000 B6 1920.000
42 23 12.26 F6 1424.696 G#6 1630.435 G#6 1669.565 C7 2086.957
43 22 −10.79 F#6 1489.455 A6 1704.545 A6 1745.455 C#7 2181.818
44 21 −30.25 G6 1560.381 A#6 1785.714 A#6 1828.571 D7 2285.714
+21.84 cent pitch
error
−44.64 cent pitch
error
−3.58 cent pitch
error
−17.26 cent pitch
error
A4 (440Hz)
Pitch Reference
frequency
C3 130.8128
C#3 138.5913
D3 146.8325
D#3 155.5635
E3 164.8138
F3 174.6143
F#3 184.9973
G3 195.9978
G#3 207.6525
A3 220.0000
A#3 233.0820
B3 246.9418
C4 261.6255
C#4 277.1825
D4 293.6650
D#4 311.1270
E4 329.6275
F4 349.2285
F#4 369.9945
G4 391.9955
G#4 415.3050
A4 440.0000
A#4 466.1640
B4 493.8835
C5 523.2510
C#5 554.3650
D5 587.3300
D#5 622.2540
E5 659.2550
F5 698.4570
F#5 739.9890
G5 783.9910
G#5 830.6100
A5 880.0000
A#5 932.3280
B5 987.7670
C6 1046.5020
C#6 1108.7300
D6 1174.6600
D#6 1244.5080
E6 1318.5100
F6 1396.9140
F#6 1479.9780
G6 1567.9820
G#6 1661.2200
A6 1760.0000
A#6 1864.6560
B6 1975.5340
C7 2093.0040
C#7 2217.4600
D7 2349.3200
SM1125 series
SEIKO NPC CORPORATION —10
Tempo
There are 29 tempos that can be selected for each melody. The tempo varies with the clock frequency.
Quarter note () length = 1536 × tempo counter frequency divider ÷ clock frequency
(Ex. 1) Tempo code = 1F (divider = 32), clock frequency = 32.768kHz (32.768kHz system)
1536 × 32 ÷ 32768 = 1.5 (seconds)
(Ex. 2) Tempo code = 18 (divider = 25), CLK frequency = 153.6kHz (38.4kHz system)
1536 × 25 ÷ 38400 = 1.0 (seconds)
Table 5. Tempo range
ROM 32.768kHz system 37.5kHz system 38.4kHz system 48kHz system
Code Frequency
divider Tempo = Tempo = Tempo = Tempo =
03 4
Prestissimo
320.0
Prestissimo
366.2
Prestissimo
375.0
Prestissimo
468.8
04 5 256.0 293.0 300.0 375.0
05 6 213.3 244.1 250.0 312.5
06 7 Presto 182.9 209.3 214.3 267.9
07 8
Allegro
160.0 Presto 183.1 Presto 187.5 234.4
08 9 142.2
Allegro
162.8
Allegro
166.7 208.3
09 10 128.0 146.5 150.0
Presto
187.5
0A 11
Moderato
116.4 133.2 136.4 170.5
0B 12 106.7 122.1 125.0
Allegro
156.3
0C 13
Andante
98.5 Moderato 112.7
Moderato
115.4 144.2
0D 14 91.4
Andante
104.6 107.1 133.9
0E 15 85.3 97.7
Andante
100.0 125.0
0F 16 80.0 91.6 93.8
Moderato
117.2
10 17
Adagio
75.3 86.2 88.2 110.3
11 18 71.1 81.4 83.3
Andante
104.2
12 19 67.4 77.1 78.9 98.7
13 20
Larghetto
64.0
Adagio
73.2
Adagio
75.0 93.8
14 21 61.0 69.8 71.4 89.3
15 22
Largo
58.2 66.6 68.2 85.2
16 23 55.7
Larghetto
63.7
Larghetto
65.2 81.5
17 24 53.3 61.0 62.5 78.1
18 25 51.2
Largo
58.6 60.0
Adagio
75.0
19 26 49.2 56.3
Largo
57.7 72.1
1A 27 47.4 54.3 55.6 69.4
1B 28 45.7 52.3 53.6 67.0
1C 29 44.1 50.5 51.7
Larghetto
64.7
1D 30 42.7 48.8 50.0 62.5
1E 31 41.3 47.3 48.4 60.5
1F 32 40.0 45.8 46.9 Largo 58.6
SM1125 series
SEIKO NPC CORPORATION —11
TYPICAL APPLICATION
External Clock Input Versions
Built-in RC Oscillator Versions
OSC
SI
SC
ST
VDD
VSS
MTO
TEST
1.5V to 3.6V
B +
CONTROLLER
2.0 to 3.6V B +
RO
CONTROLLER
CO
OSC
SI
SC
ST
VDD
VSS
MTO
TEST
SM1125 series
SEIKO NPC CORPORATION —12
OSCILLATOR FREQUENCY MEASUREMENT
The measurement circuit below shows a SM1125××V with built-in RC oscillator circuit and external RC oscil-
lator components capacitor CO and resistor RO.
When ST is switched to VDD, the oscillator starts and outputs a pulse on MTO. The output pulse is counted
using a frequency counter.
Note that the board mounting and wiring will marginally affect the output frequency, even for equivalent values for RO and CO.
OSC
SI
SC
ST
VDD
VSS
MTO
TEST
RO
CO
Switch
Frequency Counter
SM1125 V
SM1125 series
SEIKO NPC CORPORATION —13
NC9628DE 2006.04
Please pay your attention to the following points at time of using the products shown in this document.
The products shown in this document (hereinafter “Products”) are not intended to be used for the apparatus that exerts harmful influence on
human lives due to the defects, failure or malfunction of the Products. Customers are requested to obtain prior written agreement for such
use from SEIKO NPC CORPORATION (hereinafter “NPC”). Customers shall be solely responsible for, and indemnify and hold NPC free and
harmless from, any and all claims, damages, losses, expenses or lawsuits, due to such use without such agreement. NPC reserves the right
to change the specifications of the Products in order to improve the characteristic or reliability thereof. NPC makes no claim or warranty that
the contents described in this document dose not infringe any intellectual property right or other similar right owned by third parties.
Therefore, NPC shall not be responsible for such problems, even if the use is in accordance with the descriptions provided in this document.
Any descriptions including applications, circuits, and the parameters of the Products in this document are for reference to use the Products,
and shall not be guaranteed free from defect, inapplicability to the design for the mass-production products without further testing or
modification. Customers are requested not to export or re-export, directly or indirectly, the Products to any country or any entity not in
compliance with or in violation of the national export administration laws, treaties, orders and regulations. Customers are requested
appropriately take steps to obtain required permissions or approvals from appropriate government agencies.
SEIKO NPC CORPORATION
15-6, Nihombashi-kabutocho, Chuo-ku,
Tokyo 103-0026, Japan
Telephone: +81-3-6667-6601
Facsimile: +81-3-6667-6611
http://www.npc.co.jp/
Email: sales@npc.co.jp
