HA16163T

REJ03F0001-0600 Rev.6.00 Jul 01, 2008

Page 21 of 29

• Case 2

The figure below shows an example in which a current amplifier is added by means of transistors. A reverse current

due to the exciting current is prevented by a blocking diode, and therefore capacitance CB is charged. In this way,

fluctuation of the Cref potential is suppressed and stable operation can be achieved.

As well as a buffer implemented by means of a transistor, standard logic IC or buffer IC connection is also possible.

The buffer circuit power supply method should be implemented in the same way.

OUT-E

HA16163

Vref

Internal

Circuitry

Cref

CB

Blocking diode

Case 2

• Case 3

The figure below shows an example of a drive power supply method using emitter following. For the same reason

as described above, fluctuation of the Cref potential is suppressed and stable operation can be achieved.

OUT-E

HA16163

Vref

Internal

Circuitry

Cref

CB

VCC

Case 3

Supplying Power from an External Power Supply

It is also possible to use an external source as the power supply for the HA16163T as shown in figure 13. The

VREF

GOOD circuit controls whether the IC is operating or stopped. The threshold voltage of the VREFGOOD circuit

is 4.6 V (typ.) on the rising edge and 4.4 V on the falling edge. Since the IC’s characteristics vary with the value of the

external voltage, this voltage must be provided by a high-precision 5-V source.

VREF

Vcc

HA16163T

Vext

5V ± 2%

Figure 13