sames
SA9106A
SINGLE PHASE WATT MEASUREMENT IC
WITH INTEGRATED 5 DIGIT LED DISPLAY DRIVER
FEATURES
n
Performs bidirectional power measurement and directly drives a 5 digit (7
segment) LED display
n
Accuracy better than 1% (± 1 count)
n
Protected against ESD
n
Total power consumption rating below
50mW
DESCRIPTION
The SAMES SA9106A Single Phase Watt
measurement integrated circuit has an
integrated Light Emitting Diode (LED) display driver for a 5 digit (7 segment) display.
The SA9106A performs the power calculations for active power.
The method of calculation takes the power
factor into account.
The measured power is displayed in Watts
and is updated approximately every 2 seconds, given an average power reading for
this period.
This innovative universal Watt measurement integrated circuit is ideally suited for
the display of the measured power in industrial and domestic power measurement
and multi plug sockets.
The SA9106A integrated circuit is available in 40 pin dual-in-line plastic (DIP-40)
as well as 44 pin plastic leaded chip carrier
(PLCC-44) package types.
n
Adaptable to different types of current
sensors
n
Operates over a wide temperature
range
n
Precision voltage reference on-chip
PIN CONNECTIONS
V SS
V SSA
CIP
CIN
COP
CON
TP7
TP8
IVP
GND
TP11
IIN
IIP
VREF
TP15
CPON
CPOP
CPIN
CPIP
V DDA
1
40
2
39
3
38
4
37
5
36
6
35
7
34
8
33
9
32
10
31
11
30
12
29
13
28
14
27
15
26
16
25
17
24
18
23
19
22
20
21
TP40
TP39
TP38
DIG[5]
DIG[4]
DIG[3]
DIG[2]
DIG[1]
DIG[0]
OSC1
OSC2
G
F
E
D
C
B
A
TP22
V DD
DR-00235
Package: DIP-40
1/14
4008
PDS039-SA9106A-001
REV. D
10-08-1995
SA9106A
TP37
CIN
CIP
V SSA
V SS
TP40
TP39
DIG[5]
DIG[4]
39
37
38
36
35
34
33
32
31
30
29
40
28
41
27
42
26
43
25
44
24
1
23
2
22
3
21
4
20
5
19
6
18
DR-00903
8
9
10
11
12
13
14
15
CPON
CPOP
TP9
CPIN
CPIP
TP12
V DDA
V DD
7
16
DIG[3]
DIG[2]
DIG[1]
DIG[0]
OSC1
OSC2
G
F
E
D
C
17
TP22
A
B
CON
TP7
IVP
GND
TP44
TP1
IIN
IIP
TP4
TP5
VREF
COP
TP38
PIN CONNECTIONS
BLOCK DIAGRAM
V DD
V SS
IIP
POWER
IIN
ANALOG
INTEG-
LED
RATOR
DISPLAY
SIGNAL
DRIVER
PROCEVOLTAGE
REF.
SSING
IVP
GND
OSC
DR-00236
2/14
VREF
sames
OSC1
TIMING
OSC2
OUTPUTS
FOR LED
DISPLAY
SA9106A
ABSOLUTE MAXIMUM RATINGS*
Parameter
Symbol
Supply Voltage
VDD -VSS
Current on any pin
IPIN
Storage Temperature
TSTG
Operating Temperature
TO
Min
-0.3
-150
-40
-25
Max
6.0
+150
+125
+85
Unit
V
mA
°C
°C
* Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only. Functional operation of the
device at these or any other condition above those indicated in the operational sections
of this specification, is not implied. Exposure to Absolute Maximum Ratings for
extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(VDD and VDDA = 2.5V, VSS and VSSA = -2.5V, over the temperature range -10°C to +70°C#,
unless otherwise specified.)
Parameter
Symbol Min
Typ
Max
Unit Condition
Supply Voltage: Positive
VDD
2.25
2.75
V
Supply Voltage: Negative
VSS
-2.75
-2.25
V
Supply Current: Positive
IDD
5
10
mA
Supply Current: Negative
ISS
5
10
mA
-25
+25
µA
Peak value
+25
µA
Peak value
mA
mA
VOL = VSS + 0.5V
VOH = VDD - 0.5V
Current Sensor Inputs (Differential)
Input Current Range
III
Voltage Sensor Input (Asymetric)
Input Current Range
IIV
-25
Display outputs
Digit Outputs
Segment Drivers
IOL
IOH
80
20
Oscillator
Recommended crystal:
TV colour burst crystal f = 3.5795 MHz
Pin VREF
Ref. Current
Ref. Voltage
#
-IR
VR
45
1.1
50
55
1.3
µA
V
With R7 = 24kΩ
connected to VSS
Referred to VSS
Extended Operating Temperature Range available on request.
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SA9106A
PIN DESCRIPTION
Pin
PLCC
43
14
13
33
34
42
2
3
24
23
16
17
18
19
20
21
22
25
26
27
28
29
30
7
8
10
11
35
36
39
40
6
41
15
4/14
Pin
DIP
10
21
20
1
2
9
12
13
31
30
23
24
25
26
27
28
29
32
33
34
35
36
37
16
17
18
19
3
4
5
6
14
7
8
11
15
22
38
Designation
GND
VDD
VDDA
VSS
VSSA
IVP
IIN
IIP
OSC1
OSC2
A
B
C
D
E
F
G
DIG [0]
DIG [1]
DIG [2]
DIG [3]
DIG [4]
DIG [5]
CPON
CPOP
CPIN
CPIP
CIP
CIN
COP
CON
VREF
TP7
TP8
TP11
TP15
TP22
TP38
sames
Description
Ground
Positive Supply Voltage
Negative Supply Voltage
Analog input for Voltage
Inputs for current sensor
Connections for crystal or ceramic resonator
(OSC1 = Input ; OSC2 = Output)
Light Emitting Diode (LED) display segment
outputs
Light Emitting Diode (LED) display digit outputs
Connections for outer loop capacitor of A/D
converter (Voltage)
Connections for inner loop capacitor of A/D
converter (Voltage)
Connections for inner loop capacitor of A/D
converter (Current)
Connections for outer loop capacitor of A/D
converter (Current)
Connection for current setting resistor
Manufacturer's Test Pins (Leave unconnected)
SA9106A
PIN DESCRIPTION (Continued)
Pin
PLCC
31
32
1
4
5
9
12
37
38
44
Pin
DIP
39
40
Designation
TP39
TP40
TP1
TP4
TP5
TP9
TP12
TP37
TP38
TP44
Description
Manufacturer's Test Pins (Leave unconnected)
FUNCTIONAL DESCRIPTION
The SA9106A is a CMOS mixed signal Analog/Digital integrated circuit, which performs
bidirectional power calculations across a power range of 1000:1, to an overall accurancy
of better than 1% (± 1 count). An on-chip LED display driver directly drives a 5 digit (7
segment) LED display. The measured power is displayed in Watts.
The integrated circuit comprises of all the required functions such as two oversampling
A/D converters for the voltage and current sense inputs, power calculation and energy
integration. Internal offsets are eliminated through the use of cancellation procedures.
1. Power Calculation
In the Application Circuit (Figure 1), the voltage drop across the shunt will be
between 0 and 50mV (0 to 80A through a shunt resistor of 625µΩ). This voltage is
converted to a current of between 0 and 16µA, by means of resistors R 1 and R2.
The current sense input saturates at an input current of ±25µA peak.
For the voltage sense input, the mains voltage (230VAC) is divided down through
a divider to 14V. The resulting current into the A/D converter input is set at 14µA
at nominal mains voltage, via resistor R4 (1MΩ).
In this configuration, with a mains voltage of 230 V and a current of 80A, the
displayed power is 18 400 Watts.
2. LED Display Driver
The SA9106A has an on-chip LED display driver capable of driving 5 digit (7
segment) common cathode digits as well as a sign LED.
The sign LED is addressed by DIG [5], the most significant digit by DIG [4] and the
least significant digit by DIG [0].
The position of the segments a, b, c, d, e, f and g are shown in the diagram below:
sames
5/14
SA9106A
a
f
b
.
.
g
e
c
d
h
DR-00237
3.
Analog Input Configuration
The input circuitry of the current and voltage sensor inputs are illustrated below.
These inputs are protected against electrostatic discharge through clamping
diodes.
The feedback loops from the outputs of the amplifiers AI and AV generate virtual
shorts on the signal inputs. Exact duplications of the input currents are generated
for the analog signal processing circuitry.
V DD
IIP
CURRENT
SENSOR
INPUTS
V SS
A
I
V DD
IIN
V SS
V DD
IVP
VOLTAGE
SENSOR
INPUT
V SS
AV
GND
DR-00505
6/14
sames
SA9106A
4.
5.
Electrostatic Discharge (ESD) Protection
The SA9106A integrated circuit inputs/outputs are protected against ESD according
to Mil-Std 883C, method 3015.
Power Consumption
The power consumption rating of the SA9106A integrated circuit is less than 50mW,
excluding the display.
TYPICAL APPLICATIONS
In the Application Circuits (Figures 1 and 2) the components required for power
measurement applications, are shown.
In Figure 1 a shunt resistor is used for current sensing. In this application, the circuitry
requires a +2.5V, 0V, -2.5V DC supply.
In the case of Figure 2, when using a current transformer for current sensing, a +5V, 0V
DC supply is sufficient.
The most important external components for the SA9106A integrated circuit are:
C1 and C2 are the outer loop capacitors for the two integrated oversampling A/D
converters. The value of these capacitors is 560pF.
The actual values determine the signal to noise and stability performance. The tolerances
should be within ±10%.
C3 and C4 are the inner loop capacitors of the A/D converters. The optimum value is
3.3nF. The actual values are uncritical. Values smaller than 0.5nF and larger than 5nF
should be avoided.
R2, R1 and RSH are the resistors defining the current level into the current sense input.
The values should be selected for an input current of 16µA into the SA9106A at maximum
line current.
Values for RSH of less than 200µΩ should be avoided.
R1 = R2 = (IL/16µA) * RSH/2
Where IL
= Line current
RSH
= Shunt resistor/termination resistor
R3, R6 and R4 set the current for the voltage sense input. The values should be selected
so that the input current into the voltage sense input (virtual ground) is set to 14µA.
R7 together with the trimpot RT defines all on-chip bias and reference currents. The bias
resistor value (RB = R7 + RT) may be varied within ±10% for calibration purposes. Any
change to RBwill affect the displayed value quadratically (i.e.: RB = +5%, Display value
= +10%).
XTAL is a colour burst TV crystal (f = 3.5795MHz) for the oscillator. The oscillator
frequency is divided down to 1.7897MHz on-chip to supply the digital circuitry and the
A/D converters.
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7/14
SA9106A
Figure 1: Application Circuit using a Shunt Resistor for Current Sensing.
8/14
sames
SA9106A
Parts List for Application Circuit: Figure 1
Item
Symbol
Description
1
IC-1
2
D1
Light Emitting Diode
3
XTAL
Crystal, 3.5795 MHz
Colour burst TV
4
R1
Resistor, 1% metal
Note 1
5
R2
Resistor, 1% metal
Note 1
6
R3
Resistor, 390k, (230VAC) 1%, metal
7
R4
Resistor, 1M, 1/4W, 1% metal
8
R6
Resistor, 24k, 1/4W, 1% metal
9
R7
Resistor, 22k, 1/4W, 1% metal
10
R8
Resistor, (Segment G)
Note 2
11
R9
Resistor, (Segment F)
Note 2
12
R10
Resistor, (Segment E)
Note 2
13
R11
Resistor, (Segment D)
Note 2
14
R12
Resistor, (Segment C)
Note 2
15
R13
Resistor, (Segment B)
Note 2
16
R14
Resistor, (Segment A)
Note 2
17
RT
Potentiometer 4.7k
Multi turn
18
C1
Capacitor, 560pF
19
C2
Capacitor, 560pF
20
C3
Capacitor, 3.3nF
21
C4
Capacitor, 3.3nF
22
C9
Capacitor, 100nF
23
C10
Capacitor, 100nF
24
C15
Capacitor, 820nF
Note 3
25
RSH
Shunt Resistor
Note 4
SA9106A
Detail
DIP-40/PLCC-44
Note 1: Resistor (R1 and R2) values are dependant upon the selected value of RSH.
Note 2: Resistors (R8 to R14) are current limiting resistors required to set the intensity
of the LED display segments.
Note 3: Capacitor (C15) to be positioned as close to Supply Pins (VDD & VSS) of IC-1 as
possible.
Note 4: See TYPICAL APPLICATIONS when selecting the value of RSH.
sames
9/14
SA9106A
Figure 2: Application Circuit using a Current Transformer for Current Sensing.
Note: Capacitor C11 may be selected for phase compensation and DC blocking.
10/14
sames
SA9106A
Parts List for Application Circuit: Figure 2
Item
Symbol
Description
Detail
1
IC-1
SA9106A
DIP-40/PLCC-44
2
XTAL
Crystal, 3.5795MHz
Colour burst TV
3
RSH
Resistor
Note 1
4
R1
Resistor, 1%, metal
Note 2
5
R2
Resistor, 1%, metal
Note 2
6
R3
Resistor, 390k, (230 VAC). 1%, metal
7
R4
Resistor, 1M, 1/4W, 1%, metal
8
R6
Resistor, 24k, 1/4W, metal
9
R7
Resistor, 22k, 1/4W, 1%, metal
10
R8
Resistor
Note 3
11
R9
Resistor
Note 3
12
R10
Resistor
Note 3
13
R11
Resistor
Note 3
14
R12
Resistor
Note 3
15
R13
Resistor
Note 3
16
R14
Resistor
Note 3
17
R15
Resistor, 820Ω, 1/4W, 1%
18
R16
Resistor, 820Ω, 1/4W, 1%
19
D1
Light emitting diode
20
RT
Potentiometer 4.7k
21
C1
Capacitor, 560pF
22
C2
Capacitor, 560pF
23
C3
Capacitor, 3.3nF
24
C4
Capacitor, 3.3nF
25
C9
Capacitor, 100nF
26
C10
Capacitor, 100nF
27
C11
Capacitor
Note 4
28
C15
Capacitor, 820nF
Note 5
sames
Multi turn
11/14
SA9106A
Note 1:
Note 2:
Note 3:
Note 4:
Note 5:
See TYPICAL APPLICATIONS when selecting the value of RSH.
Resistor (R1and R2) values are dependant upon the selected value of RSH.
Resistors (R10 to R16) are current limiting resistors required to set the
intensity of the LED display segments.
Capacitor (C11) selected to minimize phase error introduced by current
transformer (typically 1.5µF).
Capacitor (C15) to be positioned as close to Supply Pins (VDD & VSS) of
IC-1, as possible.
ORDERING INFORMATION
Part Number
SA9106APA
SA9106AFA
12/14
Package
DIP-40
PLCC-44
sames
SA9106A
NOTES:
sames
13/14
SA9106A
Disclaimer:
The information contained in this document is confidential and proprietary to South African MicroElectronic Systems (Pty) Ltd ("SAMES") and may not be copied or disclosed to a third party, in whole or in part,
without the express written consent of SAMES. The information contained herein is current as of the date of
publication; however, delivery of this document shall not under any circumstances create any implication that the
information contained herein is correct as of any time subsequent to such date. SAMES does not undertake to
inform any recipient of this document of any changes in the information contained herein, and SAMES expressly
reserves the right to make changes in such information, without notification,even if such changes would render
information contained herein inaccurate or incomplete. SAMES makes no representation or warranty that any
circuit designed by reference to the information contained herein, will function without errors and as intended by
the designer.
Any Sales or technical questions may be posted to our e-mail address below:
[email protected]
For the latest updates on datasheets, please visit out web site:
http://www.sames.co.za
South African Micro-Electronic Systems (Pty) Ltd
P O Box 15888,
33 Eland Street,
Lynn East, 0039
Koedoespoort Industrial Area,
Republic of South Africa,
Pretoria,
Republic of South Africa
Tel:
14/14
Fax:
012 333-6021
sames
012 333-8071
Tel:
Fax:
Int +27 12 333-6021
Int +27 12 333-8071