The Leader in High Temperature
Semiconductor Solutions
CHT-LDNS-Datasheet
Version: 1.4
20-Mar-12
(Last Modification Date)
High-Temperature, Negative
2.5V; 3.3V; 5V; 5.5V; 9V; 10V; 12V; 13V or 15V,
Low-Dropout CMOS Voltage Regulator
For symmetrical voltage applications.
General Description
The CHT-LDNS is a 1A, low-dropout
negative linear voltage regulator compati-
ble with high-temperature environments.
Typical operation temperature range ex-
tends from -55°C to 225°C.
The circuit is stable throughout the whole
temperature range and under a large
choice of capacitive loads.
The minimum dropout voltage (V
in
-V
out
) is -
2V for load current up to 1A. The dropout
voltage can span from -2 Volts down to -
(1)
20 Volts .
Related documents:
AN-06016:
“Selecting correct CIS-
SOID regulator depending on your ap-
plication”
AN-06002:
“Voltage regulator short-
circuit protection and associated po-
tential startup problem”.
AN-090477:
“Power Dissipation Con-
siderations During Short Circuit Condi-
tions”
Applications
Power supplies for high-temperature elec-
tronic systems used in Well logging,
Automotive, Aeronautics or Aerospace
applications.
Features
(1)
-2V to -20V dropout Voltage
Max 1A output current @ 225°C
60dB input ripple rejection
(0-200Hz)
C
load
from 100nF to 1000µF, large
ESR range
Available in TO-254 or in custom
package on demand. (3-pin compati-
ble)
The start-up is operative over the
whole temperature range
Latch-up free
Validated at 225°C for 30000 hours
(and still on-going)
Available voltages:
CHT-LDNS-025:
CHT-LDNS-033:
CHT-LDNS-050:
CHT-LDNS-055:
CHT-LDNS-090:
CHT-LDNS-100:
CHT-LDNS-120:
CHT-LDNS-130:
CHT-LDNS-150:
-2.5V
-3.3V
-5.0V
-5.5V
-9.0V
-10.0V
-12.0V
-13.0V
-15.0V
Typical application
GND
CHT-LDNS
-V
in
≤ -V
out
-2V
C
in
C
out
R
load
V
in
V
out
-V
out
PUBLIC
Doc. DS-100613 V1.4
WWW.CISSOID.COM
1 of 8
20-Mar-12
(Last Modification Date)
Contact :
CHT-LDNS-Datasheet
Gonzalo Picún (+32-10-489214)Mar.
12
Absolute Maximum Ratings
Supply Voltage Vin
(2)
Junction Temperature (Tj)
(3)
Power dissipation
0.3…-40V
315°C
Operating Conditions
Supply Voltage
Junction temperature
(3)
Power Dissipation
-2 to -20V dropout
-55°C to 225°C
(1)
ESD Rating (expected)
Human Body Model
>1kV
CAUTION:
Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress
only rating and operation of the device at these or any other conditions above those indicated in the operational sections of this speci-
fication is not implied. Frequent or extended exposure to absolute maximum rating conditions or above may affect device reliability.
Electrical Characteristics
The following table is relative to the -15V mode (CHT-LDNS-150) with Vin=-17V (-Vout-2V).
For other nominal voltage, see notes under this table.
Parameter
Condition
Min Typ
Max
Units
note
Output voltage accu-
racy
Output voltage T°
drift
Output voltage line
regulation
Output voltage load
regulation
(i.e. R
out
)
|Vin|-|Vout|
(droupout)
Quiescent
Pin current
I
L
=10mA
-55°C <Tj <225°C
I
L
=10mA
-55°C <Tj <225°C
|Vin|=|Vout|+2V to |Vout| +
15V
I
L
=60mA, -55°C <Tj <225°C
I
L
=10mA to 1A
|Vin|=|Vout|+2V
-55°C <Tj <225°C
I
L
=1A,
-55°C <Tj <225°C
0 < I
L
<1A
-55°C
225°C
f=0Hz ..200Hz
I
load
=100mA
-55°C <Tj <225°C
10Hz-1kHz
I
L
=100mA, 25°C
-2
0
0
40
3
80
%
ppm
(4)
-3
3
mV/V
(5)
0.05
0.1
V/A
(6)
2
V
mA
3.1
3.5
(7)
Ground
Power supply rejec-
tion ratio
Foldback current
Short-circuit current
Output noise
tbd
2.7
500
tbd
3
1000
dB
A
mA
µV
RMS
(8)
(9)
Notes:
(1) |Vin| max=30V
(2) Above 225°C (T
j
), a minimum load current of 10 mA could be required.
(3) Max Power dissipation depends on packaging. CHT-LDN in TO-3 or TO-254 packages presents a “junction-to-
case” thermal resistance of maximum 5°C/W (Rth).
(4) ppm are defined as [d(Vout)/d(T)]/Vout. For -15V mode, 40ppm correspond to -600µV/°C.
(5) Defining “x” as the nominal voltage, the line regulation is better than
x/5
mV/V for |Vin|>14V and better than
x
mV/V for |Vin|≤14V.
(6) This includes the packaging parasitic resistor.
(7) Defining “x” as the nominal voltage, the typical quiescent current at 2V dropout can be approximated as
2.575+
x
*0.035 (mA) @ -55°C and 2.645+
x
*0.057 (mA) @ 225°C.
(8) Defining “x” as the nominal voltage, the minimum power supply rejection ratio is …(tbd)…
(9) Defining “x” as the nominal voltage, typical noise level is …(tbd)…
(10) Short circuit current for 2.5V typical value is 1A and max value is 1.3A
PUBLIC
Doc. DS-100613 V1.4
WWW.CISSOID.COM
2 of 8
20-Mar-12
(Last Modification Date)
Contact :
CHT-LDNS-Datasheet
Gonzalo Picún (+32-10-489214)Mar.
12
Input Capacitor and Output Load Recommended Specifications
C
in
-V
in
V
in
GND
CHT-LDNS
R
S
C
S
V
out
R
M
C
M
R
B
C
B
I
Load
³5mA
Load
A minimum load current of 5mA is required. Bellow this value, a small oscillation of few tens
of mV can occurs at the regulator output.
Resistances in series with capacitors represent the internal ESR of these capacitors.
For large capacitors:
C
B
= 0 to 1000µF
R
B
= 0.2 to
For medium capacitors:
C
M
= 0 to 6µF
R
M
=0.1 to 1
For small capacitors:
C
S
= 100n to 220nF
R
S
=10m to 50m
PUBLIC
Doc. DS-100613 V1.4
WWW.CISSOID.COM
3 of 8
20-Mar-12
(Last Modification Date)
Contact :
CHT-LDNS-Datasheet
Gonzalo Picún (+32-10-489214)Mar.
12
Operating Conditions
Start-up conditions
The start-up is operative over the whole
temperature range as long as all loads are
connected to ground. The start-up is not
guaranteed if the positive regulator output
has a current path directly connected to a
negative voltage. Indeed, such load condi-
tion can lead to wrong activation of the
short-circuit protection, i.e. a bad start-up
or a bad recovering after short-circuit. In
this case, it is recommended to use our
CHT-LDOS regulator family instead of
CHT-LDOP regulator family.
Please refer to our application notes for
more details:
AN-06016:
“Selecting correct CIS-
SOID regulator depending on your ap-
plication”
AN-06002:
“Voltage regulator short-
circuit protection and associated po-
tential startup problem”.
Fast load current transients
Output voltage overshoots and under-
shoots are ~10% of the nominal regulated
voltage when C
Load
>22µF (ESR<1ohm)
and load current transients (10mA1A)
within 1µs. For transients longer than
10µs, load capacitance of 1µF is enough.
Power dissipation considerations
When determining the maximum power
dissipated by the regulator, not only the
dissipation during normal operation must
be considered, but also the power dissi-
pated during any eventual short circuit or
overload.
During short circuit or overload, worst case
conditions are normally found for maxi-
mum Vin and a shorting resistance in the
order of few Ohms.
Entering into short-circuit or overload con-
ditions with high input voltages Vin may
lead to extreme overheating, placing the
part above Absolute Maximum Rating
conditions.
Please refer to our application note for
more detail:
AN-090477:
“Power Dissipation Con-
siderations During Short Circuit Condi-
tions”
Shorting the regulator input
If the input terminal is shorted to ground
once the output capacitance has been
charged, a large current corresponding to
the discharge of the output capacitor will
flow from the output to the input through
the drain-body diode of the internal pass
transistor. This large current may cause
the permanent damage of the part.
Sinking current or raising the output
voltage above the input voltage can
cause permanent damage to the part.
Regulator floating ground
When the ground becomes disconnected,
the output voltage gets unregulated, caus-
ing possible damage to other circuits con-
nected to Vout. If the ground terminal is
reconnected while Vin is applied, perma-
nent damage may also occur to the regu-
lator. If a regulator needs to be reconnect-
ed with the power supply on, then connect
the ground terminal first.
PUBLIC
Doc. DS-100613 V1.4
WWW.CISSOID.COM
4 of 8
20-Mar-12
(Last Modification Date)
Contact :
CHT-LDNS-Datasheet
Gonzalo Picún (+32-10-489214)Mar.
12
Typical Performance Characteristics (CHT-LDNS-150)
Note : Temperatures hereafter are ambient temperatures
16
14
12
10
8
6
4
2
0
0
0.5
1
1.5
2
2.5
3
14.9
15
-V
OUT
(V)
225
°C
15.2
150°
C
25°C
-40°C
15.1
-V
OUT
(V)
Slope < 70m
225°C
150°C
25°C
-40°C
I
Load
(A)
3.5
14.8
0
0.5
1
1.5
2
2.5
I
Load
(A)
3
Figure 1: -V
out
vs.I
Load
(@2V dropout)
Figure 2: Zoom on figure 1
0.7
0.6
0.5
0.4
15.3
I
SC
(A)
15.2
-V
OUT
(V)
15.1
0.3
0.2
0.1
0
-50
0
50
100
150
200
15
T(°C)
250
T(°C)
14.9
-50
0
50
100
150
200
250
Figure 3:Short-circuit current vs. T°
Figure 4: -Vout vs. T° (dropout=2V ; Iload=60mA, 4
samples)
2.5
-V
OUT
(V)
15.3
Max I
Load
(A)
225°C
2
Dropout=2V
15.1
25°C
1.5
1
14.9
0.5
14.7
15
20
25
V
IN
(V)
30
-50
0
0
50
100
Temperature (°C)
150
200
250
Figure 5: -Vout vs. -Vin over T° (Iload=60mA)
Figure 6: Typical max load current over T° vs. dropout
TBD
TBD
Figure 7: S
Vout
(V²/Hz)@25°C, I
load
=100mA
Figure 8: Input ripple rejection
PUBLIC
Doc. DS-100613 V1.4
WWW.CISSOID.COM
5 of 8
EE_FPGA Learning Park
京公网安备 11010802033920号
EEWORLD
