WM8945
Production Data
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
AuxADC and Touch Panel Interface
Maximum input signal
level (changes in
3.3
V
proportion to LDOVDD)
Input leakage current
AUX pin not selected as
AUXADC input
10
nA
Input resistance
50
10
pF
Input capacitance
AUXADC resolution
12
Bits
s
AUXADC conversion
time
20.8
AUXADC accuracy
6
LSB
Touch Panel switch
matrix resistance
20
Maximum Pen-Down
detection sensitivity pull-
up resistor
55
63
70
k
Touch Pressure current
source
TCH_ISEL = 0
TCH_ISEL = 1
230
460
1.65
uA
uA
V
Pen-Down detection
threshold (changes in
proportion to LDOVDD)
Digital Inputs/Outputs
Input high level
0.7DBVDD
0.8DBVDD
V
Input low level
0.3DBVDD
0.2DBVDD
V
V
Output high level
Output low level
Input capacitance
Input leakage
IOL = 1mA
IOH = -1mA
V
10
pF
nA
nA
All digital pins except CIFMODE
CIFMODE pin
-900
-90
900
90
LDO Regulator
Input voltage
LDOVDD
2.4
3.3
3.0
50
3.6
V
V
Output voltage
LDOVOUT
LDO_REF_SEL = 0
Maximum output current
(see note)
mA
Output voltage accuracy
Quiescent current
Leakage current
ILOAD = 50mA
No Load
2
%
55
1
A
A
dB
PSRR (with respect to
LDOVDD)
217Hz
1kHz
40
49
Video Buffer
Maximum output voltage
swing
Vom
Av
f=100kHz, THD=1%
1.10
5.08
-0.92
1.25
6
1.50
7.94
1.94
V pk-pk
dB
Voltage gain
VB_GAIN = 1, RREF=187,
LOAD=75, RSOURCE=75
R
VB_GAIN = 0, RREF=187,
0
dB
R
LOAD=75, RSOURCE=75
Gain step size
Differential gain
Differential phase
SNR
6
dB
%
DG
DP
Vin = 1V pk-pk
Vin = 1V pk-pk
-2.0
-2.0
40
0.3
0.7
60
+2.0
+2.0
100
Deg
dB
VSNR
PD, May 2011, Rev 4.1
12
w
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
