CHERRY CS8156YT5

CS8156
CS8156
12V, 5V Low Dropout Dual Regulator
with ENABLE
Features
Description
The CS8156 is a low dropout 12V/5V
dual output linear regulator. The 12V
± 5% output sources 750mA and the 5V
±2.0% output sources 100mA.
The regulator is protected against overvoltage conditions. Both outputs are
protected against short circuit and thermal runaway conditions.
The on board ENABLE function controls the regulatorÕs two outputs. When
the ENABLE lead is low, the regulator
is placed in SLEEP mode. Both outputs
are disabled and the regulator draws
only 200nA of quiescent current.
The CS8156 is packaged in a 5 lead
TOÐ220 with copper tab. The copper
tab can be connected to a heat sink if
necessary.
■ Two regulated outputs
12V ±5.0%; 750mA
5V ±2.0%; 100mA
■ Very low SLEEP mode
current drain 200nA
■ Fault Protection
Reverse Battery
+60V, -50V Peak
Transient Voltage
Absolute Maximum Ratings
Input Voltage
Operating Range .....................................................................-0.5V to 26V
Peak Transient Voltage (Load Dump = 46V) ....................................60V
Internal Power Dissipation ..................................................Internally Limited
Operating Temperature Range................................................-40¡C to +125¡C
Junction Temperature Range...................................................-40¡C to +150¡C
Storage Temperature Range ....................................................-65¡C to +150¡C
Lead Temperature Soldering
Wave Solder (through hole styles only)..........10 sec. max, 260¡C peak
Short Circuit
Thermal Shutdown
■ CMOS Compatible
ENABLE
Package Options
Block Diagram
5 Lead TO-220
VOUT2, 5V
VIN
ENABLE
+
+
Pre-Regulator
-
-
Tab (Gnd)
Anti-Saturation
and
Current Limit
VOUT1, 12V
Over Voltage
Shutdown
Gnd
Bandgap
Reference
+
1 VIN
Anti-Saturation
and
Current Limit
2
3
4
5
-
1
Thermal
Shutdown
VOUT1
Gnd
ENABLE
VOUT2
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. 2/19/98
1
A
¨
Company
CS8156
Electrical Characteristics for VOUT: VIN = 14.5V, IOUT1 = 5mA, IOUT2 = 5mA, -40¡C ² TJ ² +150ûC, -40¡C ² TC ² +125ûC
unless otherwise specified
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
11.2
12.0
12.8
V
■ Output Stage(VOUT1)
Output Voltage, VOUT1
13V ² VIN ² 16V, IOUT1 ² 750mA
Dropout Voltage
IOUT1 = 500mA
IOUT1 = 750mA
0.4
0.6
0.6
1.0
V
V
Line Regulation
13V ² VIN ² 16V ,5mA ² IOUT < 100mA
15
80
mV
Load Regulation
5mA ² IOUT1 ² 500mA
15
80
mV
Quiescent Current
IOUT1 ² 500mA, No Load on Standby
IOUT1 ² 750mA, No Load on Standby
45
100
125
250
mA
mA
Sleep Mode
ENABLE = Low
200
nA
Ripple Rejection
f = 120Hz, IOUT = 5mA,
VIN = 1.5VPP at 15.5VDC
42
70
dB
0.75
1.20
Current Limit
2.50
A
Maximum Line Transient
VOUT1 ² 13V
60
90
V
Reverse Polarity
Input Voltage, DC
VOUT1 ³ -0.6V, 10½ Load
-18
-30
V
Reverse Polarity Input
Voltage, Transient
1% Duty Cycle, t = 100ms, VOUT ³ -6V,
10½ Load
-50
-80
V
Output Noise Voltage
10Hz - 100kHz
Output Impedance
500mA DC and 10mA rms, 100Hz
Over-voltage Shutdown
500
µVrms
0.2
1.0
½
28
34
45
V
4.90
5.00
5.10
V
0.60
V
■ Standby Output (VOUT2)
Output Voltage, (VOUT2)
9V ² VIN ² 16V, 1mA ² IOUT2 ² 100mA
Dropout Voltage
IOUT2 ² 100mA
Line Regulation
6V ² VIN ² 26V; 1mA ² IOUT ² 100mA
5
50
mV
Load Regulation
1mA ² IOUT2 ² 100mA; 9V ² VIN ² 16V
5
50
mV
Quiescent Current
VOUT1 OFF, VOUT2 OFF, VENABLE = 0.8V
1
350
µA
Ripple Rejection
f = 120Hz; IOUT = 100mA,
VIN = 1.5VPP at 14.5VDC
42
70
dB
100
200
mA
VOUT1 Off
VOUT1 On
1.25
1.25
0.80
2.00
V
V
VENABLE ² VTHRESHOLD
-10
0
10
µA
Current Limit
■ ENABLE Function (ENABLE)
Input ENABLE Threshold
Input ENABLE Current
Package Lead Description
PACKAGE LEAD #
LEAD SYMBOL
FUNCTION
5 Lead TO-220
1
VIN
Supply voltage, usually direct from battery.
2
VOUT1
Regulated output 12V, 750mA (typ)
3
Gnd
Ground connection.
4
ENABLE
CMOS compatible input lead; switches outputs on and off.
When ENABLE is high VOUT1 and VOUT2 are active.
5
VOUT2
Regulated output 5V, 100mA (typ).
2
CS8156
Typical Performance Characteristics
Dropout Voltage vs IOUT2
VOUT1 vs. Input Voltage
13
12
2000
1800
11
10
1600
9
8
7
OUTPUT VOLTAGE (V)
Dropout Voltage (mV)
1400
1200
1000
800
600
400
RL=10W
6
5
4
3
2
1
0
200
-1
-2
0
0
50
100
150
-40
200
-20
IOUT (mA)
VOUT1 vs. Temperature
20
40
60
VOUT2 vs. Temperature
5.030
12.15
12.10
5.020
12.05
5.010
12.00
VOUT2 (V)
VOUT1 (V)
0
INPUT VOLTAGE (V)
11.95
11.90
5.000
4.990
11.85
4.980
11.80
11.75
-40
-20
0
20
40 60 80
Temp (°C)
4.970
-40
100 120 140 160
ENABLE Current vs. ENABLE Voltage
-20
0
20
40
60 80
Temp (°C)
100 120 140 160
ENABLE Current vs. ENABLE Voltage
5.0
I ENABLE (mA)
100
IENABLE (mA)
80
60
4.0
3.0
40
2.0
20
1.0
0
0
1
2
3
4
0.0
0.0
5
VENABLE (V)
5
10
15
VENABLE (V)
3
20
25
CS8156
Typical Performance Characteristics: continued
Line Transient Response (VOUT1)
Line Transient Response (VOUT2)
10
5
OUTPUT VOLTAGE
DEVIATION (mV)
IOUT1 = 500mA
10
0
-10
-20
3
2
1
0
0
10
20
30
40
50
IOUT2 = 100mA
0
-5
-10
3
INPUT VOLTAGE
CHANGE (V)
INPUT VOLTAGE
CHANGE (V)
OUTPUT VOLTAGE
DEVIATION (mV)
20
2
1
0
0
60
10
TIME (ms)
50
60
150
STANDBY
OUTPUT VOLTAGE
DEVIATION (mV)
OUTPUT VOLTAGE
DEVIATION (mV)
40
Load Transient Response (VOUT2)
150
100
50
0
-50
-100
100
50
0
-50
-100
-150
STANDBY LOAD
CURRENT (mA)
-150
0.8
0.6
0.4
0.2
20
15
10
5
0
0
0
10
20
30
40
50
60
0
10
TIME (ms)
Quiescent Current (mA)
INFINITE
HEAT SINK
16
14
12
10
8
10°C/W HEAT SINK
6
4
NO HEAT SINK
2
0
0
10
20
30
40
50
30
40
50
60
Quiescent Current vs Output Current for VOUT2
20
18
20
TIME (ms)
Maximum Power Dissipation (TO-220)
POWER DISSIPATION (W)
30
TIME (ms)
Load Transient Response (VOUT1)
LOAD
CURRENT (A)
20
60 70
80 90
150
140
130
120
110
100
90
80
70
60
50
40
30
20
10
0
No Load on 5V
VIN = 14V
25ûC
-40ûC
0
100
200
300
400
500
Output Current (mA)
AMBIENT TEMPERATURE (°C)
4
125ûC
600
700
800
CS8156
Typical Performance Characteristics: continued
Quiescent Current vs Output Current for VOUT1
Line Regulation vs Output Current for VOUT2
22
3
No Load On 12V
20
2
1
16
Line Regulation (mV)
Quiescent Current (mA)
18
VIN = 14V
14
12
10
8
-40ûC
6
25ûC
4
125ûC
2
0
25ûC
0
-40ûC
-1
125ûC
-2
-3
VIN = 6 - 26V
-4
-5
-6
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Output Current (mA)
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Output Current (mA)
Line Regulation vs Output Current for VOUT1
Load Regulation vs Output Current for VOUT2
0
-40ûC
25ûC
-4
Line Regulation (mV)
Load Regulation (mV)
-2
-6
-8
-10
-12
125ûC
-14
VIN = 14V
-16
-18
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Output Current (mA)
Load Regulation vs Output Current for VOUT1
0
-5
Load Regulation (mV)
-40ûC
-10
25ûC
-15
125ûC
-20
-25
VIN = 14V
-30
-35
-40
0
100
200
300 400 500 600
Output Current (mA)
700
800
5
25
20
15
10
5
0
-5
-10
-15
-20
-25
-30
-35
-40
VIN = 13 - 26V
125ûC
25ûC
-40ûC
0
100
100
100 100 100 100
Output Current (mA)
100
800
CS8156
Definition of Terms
Long Term Stability
Output voltage stability under accelerated life-test conditions after 1000 hours with maximum rated voltage and
junction temperature.
Dropout Voltage
The input-output voltage differential at which the circuit
ceases to regulate against further reduction in input voltage.
Measured when the output voltage has dropped 100mV
from the nominal value obtained at 14V input, dropout voltage is dependent upon load current and junction temperature.
Output Noise Voltages
The rms AC voltage at the output, with constant load and no
input ripple, measured over a specified frequency range.
Input Voltage
The DC voltage applied to the input terminals with respect
to ground.
Quiescent Current
The part of the positive input current that does not contribute to the positive load current. i.e., the regulator ground
lead current.
Input Output Differential
The voltage difference between the unregulated input voltage and the regulated output voltage for which the regulator
will operate.
Ripple Rejection
The ratio of the peak-to-peak input ripple voltage to the
peak-to-peak output ripple voltage.
Line Regulation
The change in output voltage for a change in the input voltage. The measurement is made under conditions of low dissipation or by using pulse techniques such that the average
chip temperature is not significantly affected.
Temperature Stability of VOUT
The percentage change in output voltage for a thermal variation from room temperature to either temperature extreme.
Load Regulation
The change in output voltage for a change in load current at
constant chip temperature.
Typical Circuit Waveform
60V
VIN
14V
ENABLE
2.0V
0.8V
26V
31V
14V
3V
12V
12V
12V
12V
12V
2.4V
0V
VOUT1
0V
0V
5V
5V
2.4V
VOUT2
System
Condition
0V
Turn
On
Load
Dump
Low VIN
Line Noise, Etc.
VOUT1
Short
Circuit
VOUT2
Short
Circuit
VOUT
1
Thermal
Shutdown
Turn
Off
Application Notes
To determine acceptable values for C2 and C3 for a particular application, start with a tantalum capacitor of the
recommended value and work towards a less expensive
alternative part for each output.
Step 1: Place the completed circuit with the tantalum
capacitors of the recommended value in an environmental
chamber at the lowest specified operating temperature
and monitor the outputs with an oscilloscope. A decade
box connected in series with capacitor C2will simulate the
higher ESR of an aluminum capacitor. Leave the decade
box outside the chamber, the small resistance added by
the longer leads is negligible.
Step 2: With the input voltage at its maximum value,
increase the load current slowly from zero to full load on
the output under observation. Look for any oscillations on
the output. If no oscillations are observed, the capacitor is
large enough to ensure a stable design under steady state
conditions.
Stability Considerations
The output or compensation capacitor helps determine
three main characteristics of a linear regulator: start-up
delay, load transient response and loop stability.
The capacitor value and type should be based on cost,
availability, size and temperature constraints. A tantalum
or aluminum electrolytic capacitor is best, since a film or
ceramic capacitor with almost zero ESR can cause instability. The aluminum electrolytic capacitor is the cheapest
solution, but, if the circuit operates at low temperatures
(-25¡C to -40¡C), both the value and ESR of the capacitor
will vary considerably. The capacitor manufacturers data
sheet usually provides this information.
The value for the output capacitors C2 and C3 shown in
the test and applications circuit should work for most applications, however it is not necessarily the best solution.
6
CS8156
Application Notes
Step 3: Increase the ESR of the capacitor from zero using
the decade box and vary the load current until oscillations
appear. Record the values of load current and ESR that
cause the greatest oscillation. This represents the worst
case load conditions for the output at low temperature.
Step 4: Maintain the worst case load conditions set in step
3 and vary the input voltage until the oscillations increase.
This point represents the worst case input voltage conditions.
Step 5: If the capacitor is adequate, repeat steps 3 and 4
with the next smaller valued capacitor. A smaller capacitor will usually cost less and occupy less board space. If
the output oscillates within the range of expected operating conditions, repeat steps 3 and 4 with the next larger
standard capacitor value.
Step 6: Test the load transient response by switching in
various loads at several frequencies to simulate its real
working environment. Vary the ESR to reduce ringing.
Step 7: Remove the unit from the environmental chamber
and heat the IC with a heat gun. Vary the load current as
instructed in step 5 to test for any oscillations.
Once the minimum capacitor value with the maximum
ESR is found for each output, a safety factor should be
added to allow for the tolerance of the capacitor and any
variations in regulator performance. Most good quality
aluminum electrolytic capacitors have a tolerance of +/20% so the minimum value found should be increased by
at least 50% to allow for this tolerance plus the variation
which will occur at low temperatures. The ESR of the
capacitors should be less than 50% of the maximum allowable ESR found in step 3 above.
Repeat steps 1 through 7 with C3, the capacitor on the
other output.
IIN
VIN
}
VOUT1
IOUT2
VOUT2
Control
Features
IQ
Figure 1: Dual output regulator with key performance parameters
labeled.
The value of RQJA can then be compared with those in
the package section of the data sheet. Those packages
with RQJA's less than the calculated value in equation 2
will keep the die temperature below 150¡C.
In some cases, none of the packages will be sufficient to
dissipate the heat generated by the IC, and an external
heatsink will be required.
Heat Sinks
A heat sink effectively increases the surface area of the
package to improve the flow of heat away from the IC and
into the surrounding air.
Each material in the heat flow path between the IC and the
outside environment will have a thermal resistance. Like
series electrical resistances, these resistances are summed
to determine the value of RQJA:
RQJA = RQJC + RQCS + RQSA
(3)
where
RQJC = the junctionÐtoÐcase thermal resistance,
RQCS = the caseÐtoÐheatsink thermal resistance, and
RQSA = the heatsinkÐtoÐambient thermal resistance.
RQJC appears in the package section of the data sheet. Like
RQJA, it too is a function of package type. RQCS and RQSA
are functions of the package type, heatsink and the interface between them. These values appear in heat sink data
sheets of heat sink manufacturers.
Calculating Power Dissipation
in a Dual Output Linear Regulator
The maximum power dissipation for a dual output regulator (Figure 1) is:
PD(max) = {VIN(max)ÐVOUT1(min)}IOUT1(max)+
{VIN(max)ÐVOUT2(min)}IOUT2(max)+VIN(max)IQ
IOUT1
Smart
Regulator
(1)
Where:
VIN(max) is the maximum input voltage,
Test & Application Circuit
VOUT1(min) is the minimum output voltage from VOUT1,
VOUT2(min) is the minimum output voltage fromVOUT2,
IOUT1(max) is the maximum output current for the application,
C1*
0.1mF
VIN
IOUT2(max) is the maximum output current for the application, and
C2**
22mF
+
C3**
22mF
ENABLE
Once the value of PD(max) is known, the maximum permissible value of RQJA can be calculated:
150¡C - TA
PD
+
CS8156
IQ is the quiescent current the regulator consumes at
IOUT(max).
RQJA =
VOUT1
Gnd
NOTES:
* C1 required if regulator is located far
from power supply filter.
** C2, C3 required for stability.
(2)
7
VOUT2
CS8156
Package Specification
PACKAGE DIMENSIONS IN mm(INCHES)
PACKAGE THERMAL DATA
Thermal Data
RQJC
typ
RQJA
typ
5 Lead TO-220 (T) Straight
10.54 (.415)
9.78 (.385)
2.87 (.113)
6.55 (.258) 2.62 (.103)
5.94 (.234)
1.40 (.055)
1.14 (.045)
4.83 (.190)
4.06 (.160)
5 Lead TO-220
2.0
50
ûC/W
ûC/W
5 Lead TO-220 (THA) Horizontal
4.83 (.190)
3.96 (.156)
3.71 (.146)
10.54 (.415)
9.78 (.385)
2.87 (.113)
2.62 (.103)
14.99 (.590)
14.22 (.560)
1.40 (.055)
4.06 (.160)
1.14 (.045)
3.96 (.156)
3.71 (.146)
14.99 (.590)
14.22 (.560)
6.55 (.258)
5.94 (.234)
14.22 (.560)
13.72 (.540)
2.77 (.109)
6.83 (.269)
1.02 (.040)
0.76 (.030)
1.83(.072)
1.57(.062)
1.02(.040)
0.63(.025)
1.68
(.066)
TYP
1.70 (.067)
0.81(.032)
0.56 (.022)
0.36 (.014)
2.92 (.115)
2.29 (.090)
0.56 (.022)
0.36 (.014)
6.60 (.260)
5.84 (.230)
6.81(.268)
6.93(.273)
6.68(.263)
2.92 (.115)
2.29 (.090)
5 Lead TO-220 (TVA) Vertical
4.83 (.190)
4.06 (.160)
10.54 (.415)
9.78 (.385)
3.96 (.156)
3.71 (.146)
1.40 (.055)
1.14 (.045)
6.55 (.258)
5.94 (.234)
2.87 (.113)
2.62 (.103)
14.99 (.590)
14.22 (.560)
1.78 (.070)
2.92 (.115)
2.29 (.090)
8.64 (.340)
7.87 (.310)
4.34 (.171)
1.68
(.066) typ
1.70 (.067)
0.56 (.022)
0.36 (.014)
7.51 (.296)
6.80 (.268)
.94 (.037)
.69 (.027)
Ordering Information
Part Number
CS8156YT5
CS8156YTVA5
CS8156YTHA5
Rev. 2/19/98
Description
5 Lead TO-220 Straight
5 Lead TO-220 Vertical
5 Lead TO-220 Horizontal
Cherry Semiconductor Corporation reserves the
right to make changes to the specifications without
notice. Please contact Cherry Semiconductor
Corporation for the latest available information.
8
© 1999 Cherry Semiconductor Corporation