NEC UPD4702C

DATA SHEET
MOS INTEGRATED CIRCUIT
µPD4702
INCREMENTAL ENCODER 8-BIT UP/DOWN COUNTER
CMOS INTEGRATED CIRCUITS
DESCRIPTION
The µPD4702 is 8-bit up/down counters for an incremental encoder. Two-phase (A, B) incremental input signals
are phase-differentiated, and on each signal edge, an up-count is executed if the A phase is leading, or a down-count
if the B phase is leading. Eight-bit count data is output in real time. A carry output and borrow output are also
provided for counter overflow and underflow.
The µPD4704 is also available; use of these enables the count width to be extended.
PIN CONFIGURATION (Top View)
FEATURES
• Incremental inputs (A, B)
• On-chip phase discrimination circuit (up-count mode
Reset
1
20
VDD
when the phase order is A → B, down-count mode
when B → A) 4-multiplication count method
A
2
19
Carry
• On-chip edge detection circuit
• 8-bit up/down counter latch output o Carry output,
B
3
18
Borrow
NC
4
17
STB
borrow output
• Count data output controllable (3-state output)
CD0
5
16
OE
CD1
6
15
CD7
• CMOS, single +5 V power supply
CD2
7
14
CD6
CD3
8
13
CD5
NC
9
12
CD4
VSS
10
11
NC
ORDERING INFORMATION
Part Number
Package
µPD4702C
20-pin plastic DIP
(300 mil)
µPD4702G
20-pin plastic SOP
(300 mil)
PIN NAMES
A
B
Reset

 2-phase incremental signal inputs

: Counter reset input
STB
OE
: Latch strobe signal input
: Output control signal input
CD0-7
Carry
: Count data outputs
: Carry pulse output
Borrow : Borrow pulse output
Document No. IC-3304A (2nd edition)
(O. D. No. IC-5403A)
Date Published April 1997 P
Printed in Japan
©
1993
1994
µPD4702
BLOCK DIAGRAM
Reset
Carry
A
Phase
Discrimination
Edge Detection
8-Bit Up/Down Counter
B
Borrow
8-Bit Latch
3-State Output
STB
OE
CD0–7
PIN FUNCTIONS
Pin Name
2
Input/Output
Function
A, B
Input
(Schmitt)
Incremental signal A phase and B phase signal input pins (Schmitt input)
D0 to 7
Output
(3-state)
Count data output pins. Activated when OE is “L”, high impedance outputs when OE
is “H”.
Carry
Output
8-bit counter carry signal output pin (active-low)
Borrow
Output
8-bit counter borrow signal output pin (active-low)
RESET
Input
(Schmitt)
8-bit counter reset signal output pin
Counter is reset when this pin is “H”.
OE
Input
Count data output control signal input pin
STB
Input
Counter data output latch signal. Data is latched on the fall of STB, and is held while
STB = “L”.
VDD
Power supply input pin
GND
Ground pin
µPD4702
1. DESCRIPTION OF OPERATIONS
(1) Count operation
The µPD4702 incorporates a phase discrimination circuit, and counts by 4-multiplication of the A and B input 2phase pulses. Therefore, a count operation is performed by an A input edge and a B input edge.
Fig. 1 Count Operation Timing Chart
Forward (Up-Count)
Reverse (Down-Count)
A Input
Count Operation
1
2
3
4
5
4
3
2
1
0
B Input
(2) Latch operation
An R-S flip-flop is inserted in the strobe input of the latch circuit as shown in Fig. 2, and when STB changes from
“H” to “L” during a count operation, the internal latch signal STB remains at “H” until the end of the count operation.
Therefore, the count value is latched correctly even if STB input is performed asynchronously from the A and B input
(if STB changes from “H” to “L” within tSABSTB (40 ns) after the A input or B input edge, the latch contents will be
either the pre-count or post-count value). However, when a µPD4704 is added, the correct value cannot be latched
if all digits are latched simultaneously when a carry or borrow is generated (the high-order digit may be latched
before carry/borrow transmission).
Fig. 2 STB Input Circuit
From Phase Discrimination Circuit
(Count Pulse)
STB
STB
Latched
when L
A, B Inputs
tSABSTB
STB
If tSABSTB is 40 ns or longer, the post-count value
is input to the latch.
3
µPD4702
(3) Carry & borrow outputs
If the counter performs an up-count operation when the count value is 0FFH, an active-low pulse is output to the
Carry output (the pulse width is 25 ns MIN. 120 ns MAX. irrespective of the A/B phase input cycle. Similarly, if the
counter performs a down-count operation when the count value is 00H, an active-low pulse is output to the Borrow
output.
A Borrow pulse is also output if a down-count operation is performed while RESET is “H” (during a reset), and
therefore, when a µPD4704 is added, a reset must be executed at the same time.
4
µPD4702
2. OPERATING PRECAUTIONS
As the µPD4702 incorporates an 8-bit counter, a large transient current flows in the case of a count value which
changes all the bits (such as 00H ↔ 0FFH or 7FH ↔ 080H). This will cause misoperation unless the impedance of the
power supply line is sufficiently low. It is therefore recommended that a decoupling capacitor (of around 0.1 µF)
be connected between VDD and VSS right next to the IC as shown in Fig. 3.
Fig. 3 Decoupling Capacitor
+5 V
C
VDD
µPD4702
C : 0.1 µF tantalum electrolytic laminated
ceramic capacitor, etc.
VSS
Also, if a pulse shorter than the phase difference time tSAB (70 ns) is input to the A/ B phase inputs, this will result
in a miscount. Therefore, if this kind of pulse is to be input because of encoder bounds, etc., a filter should be inserted
in the A & B phase inputs.
Fig. 4 A & B Phase Input Pulses
A Phase (or B Phase)
B Phase (or A Phase)
PW
If a pulse such that PW < 70 ns is input
in the A or B phase, there is a danger of
a miscount.
If PW is at 70 ns or more, the count value remains the same before and after pulse input. (UP count → DOWN
count or DOWN count → UP count is implemented, and therefore the the result is no change in the count value.)
5
µPD4702
ABSOLUTE MAXIMUM RATINGS (TA = 25 °C, VSS = 0 V)
PARAMETER
SYMBOL
RATING
UNIT
VDD
–0.5 to +7.0
V
Input voltage
VI
–1.0 to VDD +1.0
V
Output voltage
VO
–0.5 to VDD +0.5
V
Operating temperature
Topt
–40 to +85
°C
Storage temperature
Tstg
–65 to +150
°C
Permissible loss
PD
Supply voltage
500 (DIP)
200 (SOP)
mW
DC CHARACTERISTICS (TA = –40 to +85 °C, VDD = +5 V ±10 %)
RATING
PARAMETER
SYMBOL
TEST CONDITIONS
UNIT
MIN.
Input voltage high
VIL
MAX.
0.8
V
VIH
A, B, Reset
2.6
V
VIH
Other than the above
2.2
V
Output voltage low
VOL
IOL = 12 mA
Output voltage high
VOH
IOH = –4 mA
Static consumption current
IDD
VI = VDD, VSS
II
VI = VDD, VSS
Input voltage low
Input current
3-state output leak current
Dynamic consumption current
Hysteresis voltage
IOFF
IDD dyn
VH
0.45
VDD – 0.8
V
50
µA
–1.0
1.0
µA
–10
10
µA
12
mA
fIN = 3.6 MHz, CL = 50 pF
A, B, Reset
V
0.2
V
AC CHARACTERISTICS (TA = –40 to +85 °C, VDD = +5 V ±10 %)
PARAMETER
Cycle
tCYAB
TEST CONDITIONS
fin = 3.6 MHz
MIN.
MAX.
UNIT
280
ns
High-level width
tPWABH
140
ns
Low-level width
tPWABL
140
ns
tSAB
70
ns
Setting time
tSRSAB
0
ns
Reset time
tDRSCD
60
ns
Output delay
tDABCD
100
ns
Output delay
tDOECD
50
ns
Output delay
tDSTBCD
60
ns
Float time
tFOECD
40
ns
Carry
Output delay
tDABCB
120
ns
Borrow
Output pulse width
tPWCB
25
120
ns
RESET
Reset pulse width
tPWRS
40
ns
STB
Setting time
tSABSTB
40
ns
A, B
Phase difference time
CD0 to 7
6
SYMBOL
µPD4702
AC Timings
Fig. 1 Two-Phase Signal Input Timing
tCYAB
tPWABH
tPWABL
A
tSAB
tSAB
tSAB
tSAB
B
tPWABH
tPWABL
tCYAB
Fig. 2 Count Data Output Timing
tPWRS
Reset
tSRSAB
tSABSTB
A/B
tDRSCD
tDABCD
tDSTBCD
CD0–7
tDOECD
tFOECD
OE
STB
Fig. 3 Carry/Borrow Signal Output Timing
A/B
(CD)
(0FEH)
(0FFH)
(00)
(01)
(00)
(0FFH)
(0FEH)
(0FDH)
tDABCB
Carry
Borrow
tPWCB
tDABCB
tPWCB
7
µPD4702
Consumption Current Measurement Circuit
Measurement Conditions
A, B inputs
fIN = 3.6 MHz
A
D0
CL
B
2.6 V
D1
CL
0.8 V
STB input connected to VDD or
VDD
OE input connected to VSS.
STB
Load on all outputs, CL = 50 pF.
OE
D7
CL
AC Test Input Waveform
VIH
VIL
VIH = 2.6 V (A, B, RESET inputs)
VIH = 2.2 V (inputs other than A, B, RESET)
VIL = 0.8 V
Timing measurement is performed at 1.5 V.
8
µPD4702
Sample Application Circuits
16-bit counter
8
Data Bus
Incremental Rotary Encoder
8
A
Carry
B Borrow
8
UP
Down
CD0
CD0
STB
STB
OE
OE
R CD7
R CD7
RESET
µPD4702
µPD4704
CSL
CSH
The application circuits and their parameters are for references only and are not intended for use in actual design-in's.
9
µPD4702
RECOMMENDED SOLDERING CONDITIONS
The following conditions (see table below) must be met when soldering this product.
Please consult with our sales offices in case other soldering process is used, or in case soldering is done under
different conditions.
TYPES OF SURFACE MOUNT DEVICE
For more details, refer to our document “Semiconductor Device Mounting Technology Manual” (IEI-1207).
µPD4702G
Soldering process
*
Soldering conditions
Symbol
Infrared ray reflow
Peak package’s surface temperature: 235 °C or below,
Reflow time: 30 seconds or below (210 °C or higher),
Number of reflow process: 2, Exposure limit*: None
IR35-00-2
VPS
Peak package’s surface temperature: 215 °C or below,
Reflow time: 40 seconds or below (200 °C or higher),
Number of reflow process: 2, Exposure limit*: None
VP15-00-2
Wave soldering
Solder temperature: 260 °C or below,
Flow time: 10 seconds or below,
Number of flow process: 1, Exposure limit*: None
WS60-00-1
Partial heating method
Terminal temperature: 300 °C or below,
Flow time: 10 seconds or below,
Exposure limit*: None
Exposure limit before soldering after dry-pack package is opened.
Storage conditions: 25 °C and relative humidity at 65 % or less.
Note Do not apply more than a single process at once, except for “Partial heating method”.
TYPES OF THROUGH HOLE MOUNT DEVICE
µPD4702C
Soldering process
Wave soldering
Soldering conditions
Symbol
Solder temperature: 260 °C or below,
Flow time: 10 seconds or below
REFERENCE
Dcodument name
10
Document No.
NEC semiconductor device reliability/quality control system
IEI-1212
Quality grade on NEC semiconductor devices
IEI-1209
Semiconductor device mounting technology manual
IEI-1207
Semiconductor device package manual
IEI-1213
Guide to quality assurance for semiconductor devices
MEI-1202
Semiconductor selection guide
MF-1134
µPD4702
20PIN PLASTIC DIP (300 mil)
20
11
1
10
A
K
L
P
I
J
H
C
F
D
N
R
M
B
G
M
NOTES
1) Each lead centerline is located within 0.25 mm (0.01 inch) of
its true position (T.P.) at maximum material condition.
2) ltem "K" to center of leads when formed parallel.
ITEM MILLIMETERS
INCHES
A
B
25.40 MAX.
1.27 MAX.
1.000 MAX.
0.050 MAX.
C
2.54 (T.P.)
0.100 (T.P.)
D
0.50±0.10
0.020 +0.004
–0.005
F
1.1 MIN.
0.043 MIN.
G
H
3.5±0.3
0.51 MIN.
0.138±0.012
0.020 MIN.
I
J
4.31 MAX.
5.08 MAX.
0.170 MAX.
0.200 MAX.
K
7.62 (T.P.)
0.300 (T.P.)
L
6.4
0.252
M
0.25 +0.10
–0.05
0.010 +0.004
–0.003
N
0.25
P
0.9 MIN.
R
0~15 °
0.01
0.035 MIN.
0~15°
P20C-100-300A,C-1
11
µPD4702
20 PIN PLASTIC SOP (300 mil)
20
11
P
detail of lead end
1
10
A
H
J
E
K
F
G
I
C
N
D
M
L
B
M
NOTE
Each lead centerline is located within 0.12 mm (0.005 inch) of
its true position (T.P.) at maximum material condition.
ITEM MILLIMETERS
INCHES
A
13.00 MAX.
0.512 MAX.
B
0.78 MAX.
0.031 MAX.
C
1.27 (T.P.)
0.050 (T.P.)
D
0.40 +0.10
–0.05
0.016 +0.004
–0.003
E
0.1±0.1
0.004±0.004
F
1.8 MAX.
0.071 MAX.
G
1.55
0.061
H
7.7±0.3
0.303±0.012
I
5.6
0.220
J
1.1
0.043
K
0.20 +0.10
–0.05
0.008 +0.004
–0.002
L
0.6±0.2
M
0.12
0.005
N
0.10
0.004
P
3 ° +7°
–3°
3° +7°
–3°
0.024 +0.008
–0.009
P20GM-50-300B, C-4
12
µPD4702
[MEMO]
13
µPD4702
[MEMO]
14
µPD4702
[MEMO]
15
µPD4702
[MEMO]
No part of this document may be copied or reproduced in any form or by any means without the prior written
consent of NEC Corporation. NEC Corporation assumes no responsibility for any errors which may appear in
this document.
NEC Corporation does not assume any liability for infringement of patents, copyrights or other intellectual property
rights of third parties by or arising from use of a device described herein or any other liability arising from use
of such device. No license, either express, implied or otherwise, is granted under any patents, copyrights or other
intellectual property rights of NEC Corporation or others.
While NEC Corporation has been making continuous effort to enhance the reliability of its semiconductor devices,
the possibility of defects cannot be eliminated entirely. To minimize risks of damage or injury to persons or
property arising from a defect in an NEC semiconductor device, customers must incorporate sufficient safety
measures in its design, such as redundancy, fire-containment, and anti-failure features.
NEC devices are classified into the following three quality grades:
"Standard", "Special", and "Specific". The Specific quality grade applies only to devices developed based on a
customer designated "quality assurance program" for a specific application. The recommended applications of
a device depend on its quality grade, as indicated below. Customers must check the quality grade of each device
before using it in a particular application.
Standard: Computers, office equipment, communications equipment, test and measurement equipment,
audio and visual equipment, home electronic appliances, machine tools, personal electronic
equipment and industrial robots
Special: Transportation equipment (automobiles, trains, ships, etc.), traffic control systems, anti-disaster
systems, anti-crime systems, safety equipment and medical equipment (not specifically designed
for life support)
Specific: Aircrafts, aerospace equipment, submersible repeaters, nuclear reactor control systems, life
support systems or medical equipment for life support, etc.
The quality grade of NEC devices is "Standard" unless otherwise specified in NEC's Data Sheets or Data Books.
If customers intend to use NEC devices for applications other than those specified for Standard quality grade,
they should contact an NEC sales representative in advance.
Anti-radioactive design is not implemented in this product.
M4 96.5