BL6501A

BL6501A

BL6501A

BL6501A

Single Phase Energy Meter IC

Single Phase Energy Meter IC

Single Phase Energy Meter IC

Single Phase Energy Meter IC

http://www.belling.com.cn

- 13 -

3/1/2007

Total 15 Pages

current

sampling

V1A

V1N

V1B

0V

V1A

V1B

V1A < 87.5% V1B

to ADC

FAULT

Figure 9. Fault Conditions for Inactive Input Greater than Active Input

Power Supply Monitor

The BL6501A contains an on-chip power supply monitor. If the supply is less than 4V±5% then

the BL6501A will go in an inactive state, i.e. no energy will be accumulated when the supply

voltage is below 4V. This is useful to ensure correct device operation at power up and during

power down. The power supply monitor has built-in hysteresis and filtering. This gives a high

degree of immunity to false triggering due to noisy supplies.

The trigger level is nominally set at 4V, and the tolerance on this trigger level is about ±5%. The

power supply and decoupling for the part should be such that the ripple at VDD does not exceed

5V±5% as specified for normal operation.

SLiM technology

The BL6501A adopts the technology of SLiM (Smart Low current Management) to decrease the

static power greatly. The static power of BL6501A is about 12mW. It is half of the previous

product BL0951 (about 25mW ).This technology also decreases the request for power supply

design.

BL65XX series products used 0.35um CMOS process. The reliability and consistency are

advanced.

OPERATION MODE

Transfer Function

The BL6501A calculates the product of two voltage signals (on Channel 1 and Channel 2) and

then low-pass filters this product to extract real power information. This real power information is

then converted to a frequency. The frequency information is output on F1 and F2 in the form of

active low pulses. The pulse rate at these outputs is relatively low. It means that the frequency at

these outputs is generated from real power information accumulated over a relatively long period

of time. The result is an output frequency that is proportional to the average real power. The

average of the real power signal is implicit to the digital-to-frequency conversion. The output

frequency or pulse rate is related to the input voltage signals by the following equation. (use

3.58MHz oscillator)

2

)

(

)

(

74

.

5

REF

Z

V

F

gain

i

V

v

V

Freq

×

×

×

×

=

Freq——Output frequency on F1 and F2 (Hz)

V(v)——Differential rms voltage signal on Channel 1 (volts)