Datasheet SA9607MPA, SA9607MSA Datasheet (SAMES)

SPEC-0005 (REV. 2) 26-05-00

FEATURES

■ Provides direct interface to mechanical counters

■ Monitors Live and Neutral for tamper detection

■ Performs bidirectional energy measurement

■ Various setup modes selectable

■ Meets the IEC 521/1036 Specification for Class 1 AC Watt

hour meters

Single Phase Power/Energy Metering IC with
Tamper Detection

SA9607M

■ Total power consumption rating below 25mW

■ Adaptable to different types of sensors

■ Operates over a wide temperature range

■ Precision voltage reference on chip.

DESCRIPTION

The SAMES SA9607M is a single-phase bidirectional energy
metering integrated circuit. It provides a mono-chip solution
for energy meters with electro-mechanical displays, such as
stepper motors and impulse counters.

Two current sensor inputs allow the measurement of energy
consumption on both the live and neutral.

Direction detection of energy flow as well as other common
tamper conditions are flagged.

The power consumption on both the live and neutral are
continuously measured and the larger of the two is selected
for energy metering.

The SA9607M drives the calibration LED and the electro­mechanical counter directly.

The SA9607M integrated circuit is available in 20 pin dual-in­line plastic (DIP-20) and small outline (SOIC-20) package
types.

Figure 1: Block Diagram

1/12

IIN1
IIP1

IIP2

IVP

ANA LOG

SIGNAL

PRO-

CESSING

AND

POW ER

CAL-

CULATION

COM-

PAR ATOR

POW ER

TO

PULSE RATE

VOLTAGE

REF.

OSC

ELT

VSSVDD

SEL1

DIRO
LED
MOP
MON

RATED

VRE F

Dr-0 15 58

OSC1 OSC2 MP0MP1

POWE R 1 ( D IGITAL)

POWE R 2 ( D IGITAL)

GND

IIN2

SA9607M

http://www.sames.co.za.

2/10

ELECTRICAL CHARACTERISTICS

(VDD = 2.5V, VSS = -2.5V, over the temperature range -10°C to +70°C#, unless otherwise specified.)

ABSOLUTE MAXIMUM RATINGS*

Parameter Symbol Min Max Unit

Supply Voltage V

DD

-V

SS

-0.3 6.0 V

Current on any pin I

PIN

-150 +150 mA

Storage Temperature T

STG

-40 +125 °C

Operating Temperature T

O

-25 +85 °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.

Parameter Symbol Min Typ Max Unit Condition

Operating temp. range T

o

-25 +85 °C

Supply Voltage: Positive V

DD

2.25 2.75 V

Supply Voltage: Negative V

SS

-2.75 -2.25 V

Supply Current: Positive I

DD

56mA

Supply Current: Negative I

SS

56mA
Current Sensor Inputs (Differential)
Input Current Range I

II

-25 +25 µA Peak value
Voltage Sensor Input (Asymmetrical)
Input Current Range I

IV

-25 +25 µA Peak value
Pin DIRO, LED

Output High Voltage V

OH

VDD-1 V I

OH

= -2mA

Output Low Voltage V

OL

VSS+1 V I

OL

= 5mA

Pin MP0, MP1 Pull down
Input High Voltage V

IH

VDD-1 V

Input Low Voltage V

IL

VSS+1 V

Pin MOP, MON
Output High Voltage V

OH

VDD-1 V I

OH

= -2mA

Output Low Voltage V

OL

VSS+1 V I

OL

= 5mA

Pin RATED, SEL1, ELT Bi-direct**
Input High Voltage V

IH

VDD-1 V

Input Low voltage V

IL

VSS+1 V

Pin VREF With R = 24kΩ
Ref. Current -I

R

45 50 55 µA connected to V

SS

Ref. Voltage V

R

1.1 1.3 V Referred to V

SS

Oscillator Recommended crystal:

TV colour burst crystal f = 3.5795 MHz

#

Extended Operating Temperature Range available on request.

** Switched to output mode every 1.1 seconds for 140 µS.

SA9607M

http://www.sames.co.za.

3/10

Figure 2: Pin connections: Package: Dip-20, SOIC-20

ORDERING INFORMATION

Part Number Package

SA9607MPA DIP-20
SA9607MSA SOIC-20

PIN DESCRIPTION

DR-0155

7

1IIN1 GND

SEL1

IIP1 IVP

RATED

IIN2 DIRO

VSS

IIP2

VR EF

MP1
MP0
VD D

ELT

LED
MOP

OSC2OSC1

MON

2
3
4
5
615

14
13
12

11

10

9

8

7

16

17

18

19

20

PIN

20

8

14

19

1, 2
3, 4

5

6, 7

9, 12

13
15
16
17
18

10, 11

Description

Analog Ground. The voltage to this pin should be mid-way between V

DD

and VSS.

Positive supply voltage. The voltage to this pin is typically +2.5V if a shunt resistor is used for current sensing
or in the case of a current transformer a +5V supply can be applied.

Negative Supply Voltage. The voltage to this pin is typicall -2.5V if a shunt resistor is used for current sensing
or in the case of a current transofer a 0V supply can be applied.

The current into the A/D converter should be set at 14µA

RMS

at nominal mains voltage. The voltage sense

input saturates at an input current of ±25µA peak.
Inputs for current sensor - channel 1 and Channel 2. The shunt resistor voltage from each channel is

converted to a current of 16µA

RMS

at rated conditions. The current sense input saturates at an input current

of ±25µA peak.
This pin provides the connection for the reference current setting resistor. A 24kΩ resistor connected to V

SS

set the optimum operating condition.
Motor pulse rate select inputs. Described under Input Signals.
Motor pulse outputs. These outputs can be used to drive an impulse counter or stepper motor directly.
Calibration LED output. Refer to section Led Output (LED) for the pulse rate output options.
Rated condition select input. Described under Input Signals.
Current channel select output. This output indicates which channel is been used for kWh metering.
Earth loop tamper output. This output indicates an earth loop tamper condition.
Direction output. This output indicates the energy flow direction.
Connections for a crystal or ceramic resonator. (OSC1 = input; OSC2 = Output)

Designation

GND

V

DD

V

SS

IVP

IIN1, IIP1
IIN2, IIP2

VREF

MP0, MP1

MON, MOP

LED

RATED

SEL1

ELT

DIRO

OSC1, OSC2

SA9607M

http://www.sames.co.za.

4/10

FUNCTIONAL DESCRIPTION

The SA9607M is a CMOS mixed signal analog/digital integrated
circuit, which performs power/energy calculations across a
power range of 1000:1, to an overall accurancy of better than
Class 1.

The integrated circuit includes all the required functions for 1­phase power and energy measurement such as 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. The
SA9607M incorporates an anti-tamper scheme by continuously
measuring the power consumption on both LIVE and NEUTRAL
lines. A fault is indicated when these measurements differ by
more than 12.5%. The SA9607M generates pulses with a
frequency proportional to the larger of the two current
measurements. The source (LIVE or NEUTRAL) for these
pulses is indicated on the SEL1 pin.

Frequency outputs (MOP, MON and LED) are available. The
pulse rate on these pins follows the instantaneous active
power consumption measured.

A low voltage stepper may be driven directly from the device
by connecting it between the MOP and MON pins, alternatively
an impulse impulse counter may be driven directly by connecting
it between MOP and V

SS

.

POWER CALCULATION

In the Application Circuit (Figure 7), the voltage drop across
the shunt will be between 0 and 16mV

RMS

(0 to 80A through a
shunt resistor of 200µΩ). The voltage accross the current
transformers terminating resistor will also be between 0 and
16mV

RMS.

These voltages are converted to currents of between

0 and 16µA

RMS

for each current sense inputs by means of

resistors R

1

and R2 (channel 1) as well as R3 and R

4.

(channel

2).

The current sense input saturates at an input current of ±25µA
peak.

For the voltage sensor input, the mains voltage (230VAC) is
divided down through a divider to 14V

RMS

. The current into the

A/D converter input is set at 14µA

RMS

at nominal mains voltage,

via resistor R

6

(1MΩ).

Different pulse rates are available at the MOP and MON pins.
The device may be programmed for a 1 pulse/kWh, 10 pulses/

kWh or 100 pulses/kWh output, depending on the status of

the motor pulse rate select pins MP0 and MP1.

The LED pulse rate is fixed at 6400 pulses per kWh. Rated

conditions such as 230V/20A, 230V/40A and 230V/60A may
be chosen with the rated pin. This facility allows meter
manufacturers to cater for a wide range of metering applications
with minimal design changes.

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 A

I

and

A

V

generate virtual shorts on the signal inputs. Exact

duplications of the input currents are generated for the analog
signal processing circuitry.

ELECTROSTATIC DISCHARGE (ESD)
PROTECTION

The SA9607M integrated circuit's input's/outputs are protected
against ESD.

POWER CONSUMPTION

The power consumption rating of the SA9607M integrated
circuit is less than 30mW.

VOLTAGE
SENSOR
INPUT

IVP

D

R-01288

SS

V

CURRENT
SENSOR
INPUTS

IIP

IIN

SS

V

V

DD

SS

V

V

DD

DD

V

GND

A

V

A

I

Figure 3: Analog Input Internal Configuration

SA9607M

http://www.sames.co.za.

5/10

INPUT SIGNALS

VREF

The VREF pin is the reference for the bias resistor and is the
recommended point for calibration. With a bias resistor of
24kΩ optimum conditions are set. It may be varied within
±10% for calibration purposes. Any changes to the bias
resistor will affect the output pulse rate quadratically (i.e.(R
= +5%,(f=10%).

Motor pulse rate select (MP1 and MP0)

The pulse rate of the motor driver ouput of the SA9607M is
selected by the inputs MP1 and MP0. Three pulse rate options
are available as shown in the following table:

Pulse rate selection

OUTPUT SIGNALS

Motor output (MOP, MON)

The MON pulse will follow the MOP pulse within 142ms. This
prevents that the motor armature is in the wrong position after
a power failure. Both MOP and MON outputs are active high.
The motor drive wave forms are shown below:

LED output (LED)

The LED output pulse at a fixed rate of 6400 pulses per kWh.
The LED output is active low. The LED waveform is shown
below:

Please note that the device will not perform metering functions
as described in this document while in test mode.

Rated condition select (RATED)

The rated condition select pin gives the option of having a
3:2:1 scaling ratio of the rated current easily available. This
feature is particularly useful in circumstances where a
manufacturer requires a meter for use in a system rated for
two different conditions, for example 230V/60A and 230V/
40A. With the rated condition select the SA9607M allows for
the development of different rated meters requiring minimal
changes. The following table below lists the options available
(assuming the rated condition to be 230V/60A).

Rated condition select (RATED)

Motor drive

output

selection

Unit

MP1

MP0

V

SS

V

SS

V

DD

V

DD

V

SS

V

DD

V

SS

V

DD

1

10

100

Device test

mode

pulses/kWh
pulses/kWh
pulses/kWh

Pulse Rate Selection

Input

Signal Input RATED

V

SS

OPEN

V

DD

Rated Conditions

230V / 20A
230V / 40A
230V / 60A

Figure 5: Motor drive waveform

t

m

= 142ms

VDD

VDD

VSS

VSS

MONM

OP

t

m

t

mtm

DR -01 559

Figure 4: LED pulse output

t

LED

= 10ms

VDD

VSS

L

ED

t

LED

DR-01332

Selected input indication (SEL1)

The SA9607M continuously compares the power consumptions
on current channel 1 inputs and current channel 2 inputs. The
larger of the two measurements are used for metering. The
SEL1 output pin indicates which channel is currently being
used for the pulse output.

Signal

Output

Description

0
1

Channel 1selected (IIN1/IIP1)
Channel 2selected (IIN2/IIP2)

SEL1

Value

SA9607M

http://www.sames.co.za.

6/10

Earth loop tamper indication (ELT)

If the power measurments from both current channels differ
by more than 12.5%, (indicating a earth loop tamper condition),
the ELT output is set to zero. The SA9607M continues to
generate output pulses from the larger of the two measured
powers in this condition. The ELT output is active low.

Direction indication (DIRO)

The SA9607M provides information about the energy flow
direction on pin DIRO.

A logic 1 on pin DIRO indicates reverse energy flow. Reverse
energy flow is defined as the condition where the voltage
sense input and current sense input are out of phase (greater
than 90 degrees).

Positive energy flow, when voltage sense and current sense
input are in phase, is indicated on pin DIRO a logic 0.

The DIRO pin may be used to drive a LED in order to indicate
reverse energy.

Signal

Output

Description

1
0

Reverse energy flow
Forware energy flow

DIRO

Value

SA9607M

http://www.sames.co.za.

7/10

TYPICAL APPLICATION

In Figure 1, the components required for a stand-alone power
metering application, is shown.

Current transformers are used for mains current sensing. The
channel showing the highest power consumption will be
selected by the SA9607M for energy metering.

The most important external components for the SA9607M
integrated circuit are the current sense resistors, the voltage
sense resistors as well as the bias setting resistor.

Current Sense Resistors

The resistors R1, R2, R3 and R4 define the current level into
the current sense inputs of the device. The component should
be selected for input currents of 16µARMS into the current
channels of the SA9607M at I

MAX

(rated current of the meter).

The voltage drop of the resistors R

10

and R17 should be at least

20mV.

Where:
IL = Line current/CT-ratio
R10 = Termination resistor
R11 = Termination resistor

Voltage Sense Resistors

R9, R8, R6 and R5 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

RMS

.

Bias Resistor

R

7

defines all on-chip bias and reference currents. With R7 =

24kΩ, optimum conditions are set.
R

7

may be varied within ±10% for calibration purposes. Any

change to R

7

will affect the output quadratically (i.e.: R7 = +5%,

fP = +10%).

Current Channel 1

R1= R2= (IL/16µA

RMS

) x R10/2

Current Channel 2

R

3

= R4= (IL/16µA

RMS

) x R11/2

SA9607M

http://www.sames.co.za.

8/10

Figure 7: Application Circuit

IC - 1

SA9607 M

R8

R1

R5 R6

C4

C5

R15
R16
R17

R18

M1

PULSE

SEL

ELT

DIR

MOTOR

XTAL

C6

SUPPLY

DR-01560

NL

LOAD

N

L

R12

MOV

D1 D2

IC2

C1

D4

C2

R13

R14

D3

VSS

GND

VDD

P2

C3

R2
R3
R4
R7

R9

P1

SA9607M

http://www.sames.co.za.

9/10

Note 1: Resistor (R1, R2, R3 and R4) values are dependant upon the selected value of R10 and R11.
Note 2: See TYPICAL APPLICATION when selecting the value of R10 and R11.
Note 3: Capacitor (C6) to be positioned as closed to Supply Pins (V

DD

& VSS) of IC-1, as possible.

Note 4: Capacitor (C7) selected to minimize phase error introduced by current transformer (typically 1.5µF for normal CT5,

approx. 100nF)

Parts List for Application Circuit: Figure 7

Item Symbol Description Detail

1 IC1 SA9607M DIP-20/SOIC-20
2 D1 Diode, Silicon 1N4007
3 D2 Diode, Silicon 1N4007
4 D3 Diode, Silicon 1N4007
5 D4 Diode, Silicon 1N4007
6 D5 Light emmitting diode, Red
7 D6 Light emmitting diode, Green
8 D7 Light emmitting diode, Amber

9 D8 Light emmitting diode, Green
10 XTAL Crystal, 3.5759MHz
11 R1 Resistor, 1/4W, 1%, metal Note 1
12 R2 Resistor, 1/4W, 1%, metal Note 1
13 R3 Resistor, 1/4W, 1%, metal Note 1
14 R4 Resistor, 1/4W, 1%, metal Note 1
15 R5 Resistor, 1M, 1/4W, 1%, metal
16 R6 Resistor, 24k, 1/4W, 1%, metal
17 R7 Resistor, 22k, 1/4W, 1%, metal
18 R8 Resistor, 180k, 1/4W, 1%, metal
19 R9 Resistor, 200k, 1/4W, 1%, metal
20 R10 Resistor, 1/4W, 1%, metal Note 2
21 R11 Resistor, 1/4W, 1%, metal Note 2
22 R12 Resistor, 10Ω, 2W, Wire wound
23 R13 Resistor, 1k, 1/4W, 1%, metal
24 R14 Resistor, 1k, 1/4W, 1%, metal
25 R15 Resistor, 1k, 1/4W, 5%, carbon
26 R16 Resistor, 1k, 1/4W, 5%, carbon
27 R17 Resistor, 1k, 1/4W, 5%, carbon
28 R18 Resistor, 1k, 1/4W, 5%, carbon
29 P1 Multi-turn, Trim Pot
30 P2 Multi-turn, Trim Pot, 5k Note 2

31 C1 Capacitor, 100µF, 16V, electrolytic
32 C2 Capacitor, 100µF, 16V, electrolytic
33 C3 Capacitor Note 4
34 C4 Capacitor, 220nF
35 C5 Capacitor, 220nF
36 C6 Capacitor, 820nF Note 3
37 CT1 Current Transformer
38 CT2 Current Transformer
39 TX Transformer, 230V/9V
40 IC2 78LC05, Voltage regulator
41 M 1 Bipolar step motor
42 M0V 400V, Metal oxide varistor

SA9607M

http://www.sames.co.za.

10/10

Any Sales or technical questions may be posted to our e-mail adress below:

[e-mail]

For the latest updates on datasheets, please visit our web site:

http://www.sames.co.za.

SOUTH AFRICAN MICRO-ELECTRONIC SYSTEMS (PTY) LTD

Tel: [phone]

Tel: Int [phone]

Fax: [phone]

Fax: Int [phone]

1

DISCLAIMER:

The information contained in this document is confidential and proprietary to South African Micro-Electronic 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.

P O Box 15888
33 Eland Street

Lynn East 0039

Republic of South Africa

33 Eland Street

Koedoespoort Industrial Area

Pretoria

Republic of South Africa