CHERRY CS289GDWF20

CS289
CS289
20mA Air-Core Tachometer Drive Circuit
Description
The CS289 is specifically designed
for use with air-core meter movements. The IC has charge pump circuitry for frequency-to-voltage conversion, a shunt regulator for stable
Features
operation, a function generator, and
sine and cosine amplifiers. The
buffered sine and cosine outputs
will typically sink or source 20mA.
■ Single Supply Operation
■ On-Chip Regulation
■ 20mA Output Drive
Capability
Absolute Maximum Ratings
Supply Voltage (VCC)......................................................................................20V
Operating Temperature ............................................................Ð40¡C to +100¡C
Junction Temperature..................................................................Ð40¡C to 150¡C
Storage Temperature.................................................................Ð65¡C to +150¡C
Lead Temperature Soldering
Wave Solder (through hole styles only)...........10 sec. max, 260¡C peak
Reflow (SMD styles only)............60 sec. max above 183¡C, 230¡C peak
Package Options
Block Diagram
14L PDIP
VZ
Pwr Gnd
VCC
VCOS
VREG
SQIN
SQOUT
Regulator
F/V OUT
Charge
Pump
Pwr Gnd
1
VCC
VSINE
NC
VCOS
VBIAS
VREG
CPÐ
SQIN
CP+
SQOUT
Gnd
F/VOUT
20L SOIC Wide
(internally fused leads)
VCC
VZ 1
Function
Ð +
Generator
VZ
VSINE
VBIAS
C pÐ
C P+
Gnd
VSINE
VCOS
VBIAS
VREG
Gnd
Gnd
Gnd
Gnd
Gnd
Gnd
Gnd
Gnd
CPÐ
SQIN
CP+
SQOUT
NC
F/VOUT
Cherry Semiconductor Corporation
2000 South County Trail, East Greenwich, RI 02818
Tel: (401)885-3600 Fax: (401)885-5786
Email: info@cherry-semi.com
Web Site: www.cherry-semi.com
Rev. 3/8/99
1
A
¨
Company
CS289
Electrical Characteristics: (VCC = 13.1V, -30¡C ² TA² 85¡C)
PARAMETER
TEST CONDITIONS
Supply Current (Note 2)
MIN
TYP
VCC = 15.0V
VCC = 13.1V
VCC = 11.3V
Regulated Voltage
IREG = 4.3mA
Regulation
IREG = 0 to 5mA
MAX
UNIT
54
60
60
65
65
mA
mA
mA
8.5
9.3
V
0.10
0.20
V
2.0
4.0
mA
0.20
0.55
V
10
µA
1
15
nA
7.7
Signal Input Current
T = 25¡C
Saturation Voltage
ISQ OUT = 5mA, ISQ IN = 500µA
Leakage Current
ISQ OUT = 16V, VSQ IN = 0V
Input Current
CP+ = 0, T = 25¡C
F to V Output
VSQIN = 0 (zero input), Æ = 0¡
1.8
2.1
2.4
VCOS = 0 (Note 1), Æ = 270¡
6.3
7.1
7.9
V
EO vs. Frequency
VCOS = 0 (Note 1), Æ = 270¡, T = 25¡C
-1.5
1.5
%
Vsine at Æ = 0¡
VSQ IN = 0 (zero input), Æ = 0¡
-0.55
0.00
0.55
V
MAX Vsine+
VCOS = 0 (Note 1), Æ=90¡
3.8
4.5
5.8
V
MAX Vsine-
VCOS = 0 (Note 1), Æ = 270¡
-3.8
-4.5
-5.8
V
Coil Drive Current
VCOS = 0 (Note 1), Æ = 90¡, T = 25¡C
20
25
mA
VCOS = 0 (Note 1), Æ = 270¡
20
25
mA
Linearity
0.1
MAX VCOS+
VSQ IN = 0 (zero input), Æ = 0¡
3.8
4.5
5.8
V
MAX VCOS-
Vsine = 0 (Note 1), Æ = 180¡
-3.8
-4.5
-5.8
V
Coil Drive Current
VSQ IN = 0 (zero input), Æ = 0¡
20
25
mA
Vsine = 0 (Note 1), Æ = 180¡
20
25
mA
5.40
5.85
V
External Voltage Ref.
4.98
Note 1: Vsine measured Vsine to VZ. VCOS measured VCOS to VZ. All other voltages specified are measured to ground.
Note 2: Max PWR dissipation ²VCC X ICC - (V2 Isine + V12 ICOS).
Package Pin Description
PACKAGE PIN #
20L SO
(internally fused leads)
PIN SYMBOL
FUNCTION
14L PDIP
1
1
VZ
External Zener reference.
2
2
Vsine
Sine output signal.
3
4
VBIAS
Test pin or "0" calibration pin.
4, 5, 6, 7,
14, 15, 16, 17
7
Gnd
Analog Ground connection.
8
5
CPÐ
Negative input to charge pump.
9
6
CP+
Positive input to charge pump.
10
3
NC
No Connection
11
8
F/VOUT
Output voltage proportional to input signal frequency.
2
CS289
Package Pin Description: continued
PACKAGE PIN #
PIN SYMBOL
FUNCTION
20L SO
14L PDIP
12
9
SQOUT
Buffered square wave output signal.
13
10
SQIN
Speed or RPM input signal.
18
11
VREG
Voltage regulator output.
19
12
VCOS
Cosine output signal.
20
13
VCC
Supply voltage.
14
Pwr Gnd
Power Ground connection.
Note 1: Vsine measured Vsine to VZ. VCOS measured VCOS to VZ. All other voltages specified are measured to ground.
Note 2: Max PWR dissipation ²VCC X ICC - (V2 Isine + V12 ICOS).
Typical Performance Characteristics
Charge Pump Output Voltage
Output Angle in Polar Form
Relationship of EQ, Q and Frequency
7.1
+ V COS Q
P
6
OUTPUT
F/V Output (V)
COSINE
Q
VP SIN Q
Ð
+
5
4
3
SINE OUTPUT
VZ
2.1
Ð
F/VOUT = 2.0V + FREQ X CT X RT X VREG
0
45û
90û
135û
180û
225û
Frequency/Output Angle (°)
Function Generator Output Voltage
2.1
3.8
5.45
7.1
4.5
3.5
VSINE, VCOS (V)
VSINE
2.5
4.5V
VCOS
1.5
VZ
-1.5
-2.5
4.5V
-3.5
-4.5
0
45û
90û 135û 180û 225û
Tachometer Angular Deflection (°)
3
270û
270û
CS289
Circuit Description
Function Generator/Sine and Cosine Amplifiers
Charge Pump
The output waveforms of the sine and cosine amplifiers
are derived by On-Chip Amplifier/Comparator circuitry.
The various trip points for the circuit (i.e. 90¡, 180¡, 270¡)
are determined by an internal resistor divider connected
to the voltage regulator. The voltage EÆ is compared to
the divider network by the function generator circuitry.
Use of an external zener reference at VZ allows both sine
and cosine amplifiers to swing positive and negative with
respect to this reference. The output magnitudes and
directions have the relationship as shown in Typical
Characteristics diagrams.
The input frequency is buffered through a transistor, then
applied to the charge pump for frequency-to-voltage conversion (Figure 1). The charge pump output voltage, EÆ,
will range from 2.1V with no input (Æ= 0¡) to 7.1V at Æ =
270¡. The charge that appears on CT is reflected to COUT
through a Norton amplifier. The frequency applied at
SQIN charges and discharges CT through R1 and R2. COUT
reflects the charge as a voltage across resistor RT.
Note: Pin connections referenced are for the 14L DIP.
Function Generator Output (Æ): VCC=13.1V, TA=25¡C
Æ=ArcTan V sine (Measured angle after calibration at 180¡C)
V cos
1kW
For ÆA=45¡, 90¡, 135¡, 180¡, 225¡, 270¡, (Desired angle)
TACH INPUT
2kW
15
(ÆA-ÆM)²4.0¡
B+
18V
R2
2kW
Temperature Sensitivity: VCC=13.1V
EQ
Voltage Sensitivity: TA=25¡C
F-VOUT
SQOUT
SQIN
VREG
VCOS
(ÆÆMT)²3.5¡C, -20¡C²T²+85¡C
VCC
Gnd
ÆÆMT=ÆM (T=25¡C) -ÆM (-20¡C²T²+85¡C)
COUT
1mF
±10%
CS289
ÆÆMV=ÆM (VCC=13.1V) -ÆM (11.3V²VCC²15V)
RT
180kW
*
Gnd
CP+
CPÐ
VBIAS
NC
VZ
100W
VSINE
B+
(ÆÆMV)²2¡, 11.3V²VCC²15V
80mH
225
ZENER
5.4V
SINE
80mH
225
R1
CT
1kW
0.01mF
* ADJUST FOR TRIMMING
Figure 1. Functional Diagram of CS289 Circuit.
4
Typical values shown above apply to a nominal value of
VREG of 8.5 volts. It must be realized that trimming of RT
will be necessary to compensate for variations in regulator voltage from one unit to another.
RPM x # OF CYL. = Frequency
60
2
VF/VOUT = 2.1 + Frequency x CT x RT (VREG -0 .7)
The above equations were used in calculating the following values, where VF/VOUT = 7.1V at =270¡ and CT = 0.01 F.
An alternative to this adjustment is to replace R2 with a
potentiometer, as shown in Figure 2.
4 cylinder: Freq = 200Hz, RT = 320k½
6 cylinder: Freq = 300Hz, RT = 220k½
8 cylinder: Freq = 400Hz, RT = 150k½
F-VOUT
Gnd
CP+
CPÐ
CP
CP
Gnd
CP+
IOUT/EQ
F-VOUT
SQOUT
SQIN
TRIM
RT
RT
CPÐ
VREG
VBIAS
NC
VCOS
10kW
Partial schematic shown in Figure 3 represents one method for use with DC applications instead of frequency.
2.1V
0.7V
CT
IIN
1kW
Figure 2: Alternate Trimming Method
Figure 3: DC Application
5
CS289
Tachometer Application
CS289
Package Specification
PACKAGE THERMAL DATA
PACKAGE DIMENSIONS IN mm (INCHES)
Lead Count
14L PDIP
20L SO Wide
(internally fused leads)
Metric
Max
Min
19.69
18.67
13.00
12.60
D
Thermal Data
English
Max Min
.775 .735
.512 .496
RQJC
RQJA
typ
typ
14L
20L SOIC
PDIP Wide (internally fused leads)
48
17
¡C/W
85
90
¡C/W
Plastic DIP (N); 300 mil wide
7.11 (.280)
6.10 (.240)
8.26 (.325)
7.62 (.300)
1.77 (.070)
1.14 (.045)
2.54 (.100) BSC
3.68 (.145)
2.92 (.115)
.356 (.014)
.203 (.008)
0.39 (.015)
MIN.
.558 (.022)
.356 (.014)
REF: JEDEC MS-001
D
Some 8 and 16 lead
packages may have
1/2 lead at the end
of the package.
All specs are the same.
Surface Mount Wide Body (DW); 300 mil wide
7.60 (.299)
7.40 (.291)
10.65 (.419)
10.00 (.394)
0.51 (.020)
0.33 (.013)
1.27 (.050) BSC
2.49 (.098)
2.24 (.088)
1.27 (.050)
0.40 (.016)
2.65 (.104)
2.35 (.093)
0.32 (.013)
0.23 (.009)
D
REF: JEDEC MS-013
0.30 (.012)
0.10 (.004)
Ordering Information
Part Number
Description
CS289GDWF20 20 Lead SO Wide (internally fused leads)
CS289GDWFR20 20 Lead SO Wide (internally fused leads)
(tape & reel)
CS289GN14
14 Lead PDIP
Rev. 3/8/99
Cherry Semiconductor Corporation reserves the
right to make changes to the specifications without
notice. Please contact Cherry Semiconductor
Corporation for the latest available information.
6
© 1999 Cherry Semiconductor Corporation