as5043 austriamicrosystems, as5043 Datasheet - Page 14

• Manufacturer Part Number: as5043
• Description: 10-bit Programmable 360? Magnetic Angle Encoder With Absolute Digital And Analog Outputs
• Manufacturer: austriamicrosystems

P R O G
AS5043 Programmable 360° Magnetic Angle Encoder
where:
V
TN
VDD5V
V
13 Analog Readback Mode
Non-volatile programming (OTP) uses on-chip zener
diodes, which become permanently low resistive when
subjected to a specified reverse current.
The quality of the programming process depends on the
amount of current that is applied during the programming
process (up to 130mA). This current must be provided by
an external voltage source. If this voltage source cannot
provide adequate power, the zener diodes may not be
programmed properly.
In order to verify the quality of the programmed bits, an
analog level can be read for each zener diode, giving an
indication whether this particular bit was properly
programmed or not.
To put the AS5043 in Analog Readback Mode, a digital
sequence must be applied to pins CSn, PROG and CLK
as shown in Figure 15. The digital level for this pin
depends on the supply configuration (3.3V or 5V; see
section 7, page 4).
The second rising edge on CSn (OutpEN) changes pin
PROG to a digital output and the log. high signal at pin
PROG must be removed to avoid collision of outputs
(grey area in Figure 15).
Revision 1.6, 3-Oct-06
C S n
C L K
noise, Vout
noise,OPAMP
P ro g E N
t
L o a d P ro g
= noise level at pin Vout in Vrms
= transition noise (in °rms; see 19.5)
= Supply voltage VDD5V in V
= noise level of OPAMP
(paragraph 19.3.6) in Vrms
O u tp E N
In te rn a l
te st b it
d ig ita l
P ro g c h a n g es to O u tp ut
V
re f
O R 0
1
O R 1
Figure 15:Analog OTP Register Read
www.austriamicrosystems.com
C la m p
M d E N
C L K
A n a log R e a d b a ck D a ta a t P R O G
R e fE xt
E N
A re a d
V
u n p ro g ra m m e d
V
p ro g ra m m e d
12.7 Application Examples
See Application Note AN5043-10 for AS5043 Application
Examples.
The following falling slope of CSn changes pin PROG to
an analog output, providing a reference voltage V
must be saved as a reference for the calculation of the
subsequent programmed and unprogrammed OTP bits.
Following this step, each rising slope of CLK outputs one
bit of data in the reverse order as during programming.
(see Figure 15: Output Range OR0 and -1 , ClampMdEn,
RefExtEn, FB_IntEn, Z0…Z9, ccw)
During analog readback, the capacitor at pin PROG (see
Figure 12) should be removed to allow a fast readout
rate.
The measured analog voltage for each bit must be
subtracted from the previously measured V
resulting value gives an indication on the quality of the
programmed bit: a reading of <100mV indicates a
properly programmed bit and a reading of >1V indicates
a properly unprogrammed bit.
A reading between 100mV and 1V indicates a faulty bit,
which may result in an undefined digital value, when the
OTP is read at power-up.
Following the 16
must be reset by disconnecting the power supply.
Z 5
Z 6
th
clock (after reading bit “ccw”), the chip
Z 7
Z 8
Z 9
1 6
ccw
P o w e r-o n -
R e se t;
cyc le
su p p ly
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Page 14 of 26
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