Rainbow Electronics DS1807 User Manual
Page 12
DS1807
12 of 13
110499
NOTES:
1. All voltages are referenced to ground.
2. I/O pins of fast mode devices must not obstruct the SDA and SCL lines if V
DD
is switched off.
3. I
CC
specified with zero-crossing detection active and operating device serial port in fast mode.
4. I
STBY
specified with for V
CC
equal 3.0V and 5.0V and SDA and SCL are driven to the appropriate
logic levels. I
STBY
is specified as the current consumption of the device when SDA and SCL are in the
inactive (high) states.
5. After this period, the first clock pulse is generated.
6. A device must internally provide a hold time of at least 300 ns for the SDA signal (referred to the
V
IHMIN
of the SCL signal) in order to bridge the undefined region of the falling edge of SCL.
7. The maximum t
HD:DAT
has only to be met if the device does not stretch the LOW period (t
LOW
) of the
SCL signal.
8. A fast mode device can be used in a standard mode system, but the requirement t
SU:DAT
> 250 ns must
then be met. This will automatically be the case if the device does not stretch the LOW period of the
SCL signal. If such a device does stretch the LOW period of the SCL signal, it must output the next
data bit to the SDA line t
RMAX
+ t
SU:DAT
= 1000+250=1250 ns before the SCL line is released.
9. C
B
- total capacitance of one bus line in picofarads, timing referenced to (0.9(V
CC
) and (0.1)(V
CC
)).
10. Absolute tolerance is used to determine measured wiper voltage versus expected wiper voltage as
determined by wiper position.
11. Tap-to-tap tolerance is used to determine the change in voltage between successive tap positions. The
DS1807 is specified for a
±0.25 dB tap-to-tap tolerance.
12. Typical values are for t
A
= 25
°C and nominal supply voltage.
13. Address inputs, A0, A1, and A2, should be tied to either V
CC
or GND depending on the desired
address selections.
14. These parameters are characterized and not 100% tested.
15. Interchannel matching is used to determine the relative difference in dB between the same position on
each potentiometer. The DS1807 is specified for
±0.5 dB Interchannel matching
16. See Figure 9.
17. Valid at 25
°C only.