Order this document by MC3425/D
MC3425
Power Supply Supervisory/
Over and Undervoltage
Protection Circuit
The MC3425 is a power supply supervisory circuit containing all the
necessary functions required to monitor over and undervoltage fault
conditions. These integrated circuits contain dedicated over and
undervoltage sensing channels with independently programmable time
delays. The overvoltage channel has a high current Drive Output for use in
conjunction with an external SCR Crowbar for shutdown. The undervoltage
channel input comparator has hysteresis which is externally programmable,
and an open–collector output for fault indication.
•
Dedicated Over and Undervoltage Sensing
POWER SUPPLY SUPERVISORY/
OVER AND UNDERVOLTAGE
PROTECTION CIRCUIT
SEMICONDUCTOR
TECHNICAL DATA
•
•
•
•
•
•
Programmable Hysteresis of Undervoltage Comparator
Internal 2.5 V Reference
300 mA Overvoltage Drive Output
30 mA Undervoltage Indicator Output
Programmable Time Delays
4.5 V to 40 V Operation
8
1
P1 SUFFIX
PLASTIC PACKAGE
CASE 626
Symbol
VCC
VIR
IOS(DRV)
VIND
IIND
PD
R
θJA
TJ
TA
Tstg
Value
40
–0.3 to +40
Internally
Limited
0 to 40
30
1000
80
+150
0 to +70
–55 to +150
Unit
Vdc
Vdc
mA
Vdc
mA
mW
°C/W
°C
°C
°C
O.V. DRV
Output
O.V. DLY
O.V. Sense
U.V. Sense
1
2
3
4
(Top View)
Vout
8
7
6
5
VCC
Gnd
U.V. IND
Output
U.V. DLY
MAXIMUM RATINGS
Rating
Power Supply Voltage
Comparator Input Voltage Range (Note 1)
Drive Output Short Circuit Current
Indicator Output Voltage
Indicator Output Sink Current
Power Dissipation and Thermal Characteristics
Maximum Power Dissipation @ TA = 70°C
Thermal Resistance, Junction–to–Air
Operating Junction Temperature
Operating Ambient Temperature Range
Storage Temperature Range
PIN CONNECTIONS
NOTE:
1. The input signal voltage should not be allowed to go negative by more than 300 mV
NOTE:
1.
or positive by more than 40 V, independent of VCC, without device destruction.
Simplified Application
Overvoltage Crowbar Protection, Undervoltage Indication
Vin
DC
Power
Supply
+
Cout
MC3425
Undervoltage
Indication
Device
ORDERING INFORMATION
Operating
Temperature Range
TA = 0° to +70°C
Package
Plastic DIP
Rev 2
MC3425P1
©
Motorola, Inc. 1996
MOTOROLA ANALOG IC DEVICE DATA
1
MC3425
ELECTRICAL CHARACTERISTICS
(4.5 V
≤
VCC
≤
40 V; TA = Tlow to Thigh [Note 2], unless otherwise noted.)
Characteristics
REFERENCE SECTION
Sense Trip Voltage (Referenced Voltage)
VCC = 15 V
TA= 25°C
Tlow to Thigh (Note 2)
Line Regulation of VSense
4.5 V
≤
VCC
≤
40 V; TJ = 25°C
Power Supply Voltage Operating Range
Power Supply Current
VCC = 40 V; TA = 25°C; No Output Loads
O.V. Sense (Pin 3) = 0 V;
U.V. Sense (Pin 4) = VCC
O.V. Sense (Pin 3) = VCC;
U.V. Sense (Pin 4) = 0 V
INPUT SECTION
Input Bias Current, O.V. and U.V. Sense
Hysteresis Activation Voltage, U.V. Sense
VCC = 15 V; TA = 25°C;
IH = 10%
IH = 90%
Hysteresis Current, U.V. Sense
VCC = 15 V; TA = 25°C; U.V. Sense (Pin 4) = 2.5 V
Delay Pin Voltage (IDLY = 0 mA)
Low State
High State
Delay Pin Source Current
VCC = 15 V; VDLY = 0 V
Delay Pin Sink Current
VCC = 15 V; VDLY = 2.5V
OUTPUT SECTION
Drive Output Peak Current (TA = 25°C)
Drive Output Voltage
IDRV = 100 mA; TA = 25° C
Drive Output Leakage Current
VDRV = 0 V
Drive Output Current Slew Rate (TA = 25°C)
Drive Output VCC Transient Rejection
VCC = 0 V to 15 V at dV/dt = 200 V
µs;
O.V. Sense (Pin 3) = 0 V; TA = 25°C
Indicator Output Saturation Voltage
IIND = 30 mA; TA = 25°C
Indicator Output Leakage Current
VOH(IND) = 40 V
Output Comparator Threshold Voltage (Note 3)
Propagation Delay Time
(VCC = 15 V; TA = 25°C)
Input to Drive Output or Indicator Output
100 mV Overdrive, CDLY = 0
µF
Input to Delay
2.5 V Overdrive (0 V to 5.0 V Step)
IDRV(peak)
VOH(DRV)
IDRV(leak)
di/dt
IDRV(trans)
200
VCC–2.5
–
–
–
300
VCC–2.0
15
2.0
1.0
–
–
200
–
–
mA
V
nA
A/µs
mA
(Peak)
mV
nA
V
IIB
VH(act)
–
–
IH
9.0
0.6
0.8
12.5
–
–
16
µA
V
VOL(DLY)
VOH(DLY)
IDLY(source)
IDLY(sink)
–
VCC–0.5
140
1.8
0.2
VCC–0.15
200
3.0
0.5
–
260
–
µA
mA
–
1.0
2.0
µA
V
VSense
2.4
2.33
Regline
VCC
–
4.5
2.5
2.5
7.0
–
2.6
2.63
15
40
mV
Vdc
Vdc
Symbol
Min
Typ
Max
Unit
ICC(off)
ICC(on)
–
–
8.5
16.5
10
19
mA
mA
VIND(sat)
IIND(leak)
Vth(OC)
–
–
2.33
560
25
2.5
800
200
2.63
tPLH(IN/OUT)
tPLH(IN//DLY)
–
–
1.7
700
–
–
µs
ns
NOTES:
2. Tlow to Thigh = 0° to +70°C
3. The Vth(OC) limits are approximately the VSense limits over the applicable temperature range.
2
MOTOROLA ANALOG IC DEVICE DATA
MC3425
Figure 1. Hysteresis Current versus
Hysteresis Activation Voltage
14
IH, HYSTERESIS CURRENT (
µ
A)
12
10
8.0
6.0
4.0
2.0
0
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
VH(act), HYSTERESIS ACTIVATION VOLTAGE (V)
1.6
VCC = 40 V
VCC
= 15 V
TA = 25°C
V H(act) , HYSTERESIS ACTIVATION VOLTAGE (V)
Figure 2. Hysteresis Activation Voltage
versus Temperature
1.2
1.0
0.8
0.6
0.4
0.2
0
–55
VCC = 5.0 V
VCC = 15 V
VCC = 40 V
VH(act) = Voltage Level at
which Hysteresis Current
(IH) is 90% of full value.
VCC = 5.0 V
–25
0
25
50
75
TA, AMBIENT TEMPERATURE (°C)
100
125
15.0
IH, HYSTERESIS CURRENT (
µ
A)
U.V. Sense = 2.5 V
14.0
13.0
12.0
11.0
10.0
–55
∆
V Sense , SENSE TRIP VOLTAGE CHANGE (mW)
Figure 3. Hysteresis Current
versus Temperature
Figure 4. Sense Trip Voltage Change
versus Temperature
0
–10
–20
–30
–40
–50
–55
–25
0
25
50
75
100
125
VCC = 15 V
*VSense at TA = 25°C
VSense* = 2.400 V
* = 2.500 V
* = 2.600 V
–25
0
25
50
75
TA, AMBIENT TEMPERATURE (°C)
100
125
TA, AMBIENT TEMPERATURE (°C)
IDLY(source), DELAY PIN SOURCE CURRENT (
µ
A)
Figure 5. Output Delay Time versus
Delay Capacitance
100
t DLY , OUTPUT DELAY TIME (mS)
10
1.0
0.1
0.01
VCC = 15 V
TA = 25°C
Figure 6. Delay Pin Source Current
versus Temperature
260
240
220
VCC = 15 V
200
180
160
–55
VCC = 5.0 V
VCC = 40 V
2.5 CDLY
tDLY =
200
µA
0.001
0.0001
0.001
0.01
0.1
1.0
10
–25
CDLY, DELAY PIN CAPACITANCE (µF)
0
25
50
75
TA, AMBIENT TEMPERATURE (°C)
100
125
MOTOROLA ANALOG IC DEVICE DATA
3
MC3425
V OH(DRV), DRIVE OUTPUT SATURATION VOLTAGE (V)
V IND(sat) , INDICATOR OUTPUT SATURATION VOLTAGE (V)
Figure 7. Drive Output Saturation Voltage
versus Output Peak Current
5.0
4.0
3.0
2.0
1.0
0
VCC = 15 V
1.0% Duty Cycle @ 300 Hz
TA = 25°C
Figure 8. Indicator Output Saturation Voltage
versus Output Sink Current
0.4
0.3
0.2
VCC = 15 V
TA = 25°C
0.1
0
100
200
300
400
0
0
10
20
30
40
IIND, INDICATOR OUTPUT SINK CURRENT (mA)
IDRV(peak), DRIVE OUTPUT PEAK CURRENT (mA)
V OH(DRV), DRIVE OUTPUT SATURATION VOTLAGE (V)
Figure 9. Drive Output Saturation Voltage
versus Temperature
2.500
2.460
2.420
2.380
2.340
2.300
–55
VCC = 15 V
IDRV(peak) = 200 mA
1.0% Duty Cycle @ 300 Hz
I CC, POWER SUPPLY CURRENT (mA)
28
24
20
16
12
8.0
4.0
0
–25
0
25
50
75
100
125
0
5.0
Figure 10. Power Supply Current
versus Voltage
Curve O.V. Sense U.V. Sense
A
VCC
Gnd
B
Gnd
VCC
A
B
TA = 25°C
10
15
20
25
30
35
40
TA, AMBIENT TEMPERATURE (°C)
VCC, POWER SUPPLY VOLTAGE (V)
4
MOTOROLA ANALOG IC DEVICE DATA
MC3425
APPLICATIONS INFORMATION
Figure 11. Overvoltage Protection and
Undervoltage Fault Indication with
Programmable Delay
+VO
Vin
Figure 12. Overvoltage Protection of 5.0 V
Supply with Line Loss Detector
VO = 5.0 V
VO(trip) = 6.25 V
8
VCC
4
U.V.
Sense
MC3425
3
O.V.
Sense
O.V. 1
DRV
U.V. 6
IND
1.0k
Line Loss
Output
+5.0V
Power
Supply
15k
R1A
R1B
8
VCC
4
IH
3
U.V.
Sense
MC3425
O.V.
Sense
O.V. 1
DRV
U.V. 6
IND
+
Power
Supply
4.5V to 40V
–
AC Line
U.V. Fault
Indicator
10k
100
U.V.
O.V.
DLY Gnd DLY
2
7
5
0.01µF
0.33µF
R2A
R2B
CDLY
U.V.
O.V.
DLY
DLY Gnd
2
7
5
CDLY
Gnd
R1A
1+
R2A
U.V. Sense
Pin 4
U.V. DLY
Pin 5
U.V. IND
Pin 6
2.5V
2.5V
OFF
ON
U.V. Hysteresis = IH
tDLY = 12500 CDLY
R1B R2B
, VO(trip) – 2.5 V
R1B + R2B
Figure 13. Overvoltage Audio Alarm Circuit
Figure 14. Programmable Frequency Switch
12V
8
VCC
3
10k
O.V.
Sense
MC3425
4
U.V.
Sense
O.V.
U.V.
DLY Gnd DLY
5
7
2
CDLY
O.V. 1
DRV
+VO
8
12k
3 O.V.
Sense
2.7k
4
82k
6.8k
0.1µF
Gnd
U.V.
Sense
U.V. O.V.
DLY DLY Gnd
5
2
7
VCC
O.V.
DRV
1
Alarm On when:
VO = 13.6 V
Input Signal
I.V. p–p
5.0µF
10k
Output Pulse when:
1
f(input) <
25000 CDLY
1.0k
+
12V
Power
Supply
MC3425
100Ω
0.1µF
O.V. Sense
Pin 3
O.V. DLY
Pin 2
O.V. DRV
Pin 1
2.5V
2.5V
ON
OFF
MOTOROLA ANALOG IC DEVICE DATA
5
