Semiconductor Components Industries, LLC, 2001
December, 2001 – Rev. 6
1
Publication Order Number:
CS4192/D
CS4192
Single Air-Core Gauge
Driver
The CS4192 is a monolithic BiCMOS integrated circuit used to
translate a digital 10–bit word from a microprocessor/microcontroller
to complementary DC outputs. The DC outputs drive an air–core
meter commonly used in vehicle instrument panels. The 10 bits of data
are used to linearly control the quadrature coils of the meter directly
with a 0.35
°
resolution and
±
1.2
°
accuracy over the full 360
°
range of
the gauge. The interface from the microcontroller is by a Serial
Peripheral Interface (SPI) compatible serial connection using up to a
2.0 MHz shift clock rate.
The digital code, which is directly proportional to the desired gauge
pointer deflection, is shifted into a DAC and multiplexer. These two
blocks provide a tangential conversion function to change the digital
data into the appropriate DC coil voltage for the angle demanded. The
tangential algorithm creates approximately 40% more torque in the
meter movement than does a sin–cos algorithm at 45
°
, 135
°
, 225
°
, and
315
°
angles. This increased torque reduces the error due to pointer
droop at these critical angles.
Each output buffer is capable of supplying up to 70 mA per coil and
the buffers are controlled by a common OE enable pin. The output
buffers are turned off when OE is brought low, while the logic portion
of the chip remains powered and continues to operate normally. OE
must be high before the falling edge of CS to enable the output buffers.
The status pin (ST) reflects the state of the outputs and is low
whenever the outputs are disabled.
The Serial Gauge Driver is self–protected against fault conditions.
Each driver is protected for 125 mA (typ.) overcurrent while a global
thermal protection circuit limits junction temperature to 170
°
C (typ.).
The output drivers are disabled anytime the IC protection circuitry
detects an overcurrent or overtemperature fault. The drivers remain
disabled until a falling edge is presented on CS. If the fault is still
present, the output drivers automatically disable themselves again.
Features
Serial Input Bus
2.0 MHz Operating Frequency
Tangential Drive Algorithm
70 mA Drive Circuits
0.5
°
Accuracy (Typ.)
Power–On–Reset
Protection Features
–
Output Short Circuit
–
Overtemperature
Internally Fused Leads in SO–16L Package
http://onsemi.com
A
WL, L
YY, Y
WW, W
= Assembly Location
= Wafer Lot
= Year
= Work Week
PIN CONNECTION AND
MARKING DIAGRAM
Device
Package
Shipping
ORDERING INFORMATION
CS4192XDWF16
SO–16L
46 Units/Rail
CS4192XDWFR16
SO–16L
1000 Tape & Reel
SO–16L
DWF SUFFIX
CASE 751G
1
16
C
A
SCLK
OE
1
16
CS
V
CC
ST
SI
GND
GND
GND
GND
SO
V
BB
COS–
SIN+
COS+
SIN–