AS1506BTDT100 austriamicrosystems, AS1506BTDT100 Datasheet - Page 13

• Manufacturer Part Number: AS1506BTDT100
• Description: IC, DIGITAL POT 100KOHM, 256, SGL TDFN-8
• Manufacturer: austriamicrosystems

Specifications of AS1506BTDT100

• End To End Resistance: 100kohm
• Track Taper: Linear
• No. Of Steps: 256
• Supply Voltage Range: 2.7V To 5.5V
• Control Interface: Serial, SPI
• No. Of Pots: Single
• Memory Type: EEPROM
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

AS1506
Data Sheet - A p p l i c a t i o n I n f o r m a t i o n
9 Application Information
The AS1506 is intended for circuits requiring digitally controlled adjustable resistance, such as LCD contrast control
(where voltage biasing adjusts the display contrast), or programmable filters with adjustable gain and/or cutoff fre-
quency.
Programmable Filter
Figure 24
The DC gain of the filter is adjusted by R
The cutoff frequency (f
Figure 24. Programmable Filter Circuit
Offset Voltage and Gain Adjustment
Connect the AS1506 to an op amp to nullify the offset voltage over the operating temperature range. Install another
AS1506 potentiometer in the feedback path to adjust the gain of the op amp
Figure 25. Offset Voltage Adjustment Circuit
www.austriamicrosystems.com
shows the configuration for a 1st-order programmable filter.
C
) is adjusted by R
V
AS1506
IN
C
IN
HIGH
2
LOW
3
and can be calculated as:
R
, and can be calculated as:
3
AS1506
f
C
G = 1 + (R
= 1/(2
WIPER
5V
HIGH
LOW
+
–
Revision 1.01
R
π
2
x R
1
/R
3
+
–
WIPER
x C)
2
)
R
AS1506
1
V
OUT
(Figure
25).
13 - 17
(EQ 1)
(EQ 2)