19-2082; Rev 0; 7/01
KIT
ATION
EVALU
E
BL
AVAILA
Current-Mode PWM Controllers with Integrated
Startup Circuit for Isolated Power Supplies
General Description
The MAX5014/MAX5015 integrate all the building
blocks necessary for implementing DC-DC fixed-fre-
quency isolated power supplies. These devices are
current-mode controllers with an integrated high-volt-
age startup circuit suitable for isolated telecom/industri-
al voltage range power supplies. Current-mode control
with leading-edge blanking simplifies control-loop
design and internal ramp compensation circuitry stabi-
lizes the current loop when operating at duty cycles
above 50% (MAX5014). The MAX5014 allows 85%
operating duty cycle and could be used to implement
flyback converters, whereas the MAX5015 limits the
operating duty cycle to less than 50% and can be used
in single-ended forward converters. A high-voltage
startup circuit allows these devices to draw power
directly from the 18V to 110V input supply during start-
up. The switching frequency is internally trimmed to
275kHz ±10%, thus reducing magnetics and filter com-
ponent costs.
The MAX5014/MAX5015 are available in 8-pin SO
packages. An evaluation kit (MAX5015EVKIT) is also
available.
Warning:
The MAX5014/MAX5015 are designed to
operate with high voltages. Exercise caution.
o
Current-Mode Control
o
Leading-Edge Blanking
o
Internally Trimmed 275kHz ±10% Oscillator
o
Low External Component Count
o
Soft-Start
o
High-Voltage Startup Circuit
o
Pulse-by-Pulse Current Limiting
o
Thermal Shutdown
o
SO-8 Package
Features
o
Wide Input Range: (18V to 110V) or (13V to 36V)
MAX5014/MAX5015
Ordering Information
PART
MAX5014CSA*
MAX5014ESA*
MAX5015CSA*
TEMP. RANGE
0°C to +70°C
-40°C to +85°C
0°C to +70°C
PIN-PACKAGE
8-SO
8-SO
8-SO
8-SO
MAX5015ESA*
-40°C to +85°C
*See Selector Guide at end of data sheet.
Applications
Telecom Power Supplies
Industrial Power Supplies
Networking Power Supplies
Isolated Power Supplies
V
IN
Typical Operating Circuit
V
OUT
V+
V
DD
NDRV
Pin Configuration
TOP VIEW
CS
MAX5015
GND
SS_SHDN
V
CC
V+
1
V
DD
OPTO
2
3
8
7
V
CC
NDRV
GND
CS
OPTO
OPTOCOUPLER
MAX5014/
MAX5015
6
5
SS_SHDN
4
8-SO
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
Current-Mode PWM Controllers with Integrated
Startup Circuit for Isolated Power Supplies
MAX5014/MAX5015
ABSOLUTE MAXIMUM RATINGS
V+ to GND ……………………………………...……-0.3V to +120V
V
DD
to GND.………………………………….……….-0.3V to +40V
V
CC
to GND.………………….……………………-0.3V to +12.5V
OPTO, NDRV, SS_SHDN, CS to GND .……-0.3V to V
CC
+ 0.3V
V
DD
and V
CC
Current …………………...…………………..20mA
NDRV Current Continuous...………………………………….25mA
NDRV Current for Less than 1µs..………….…………….……±1A
Continuous Power Dissipation (T
A
= +70°C)
8-Pin SO (derate 5.88mW/°C above +70°C) .………....471mW
Operating Temperature Range…………..……...-40°C to +85°C
Storage Temperature Range……………..…….-65°C to +150°C
Lead Temperature (soldering, 10s) ……………… ………+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(V
DD
= 13V, a 10µF capacitor connects V
CC
to GND, V
CS
= 0, V+ = 48V, 0.1µF capacitor connected to SS_SHDN, NDRV = open cir-
cuit, OPTO = GND, T
A
= -40°C to +85°C, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
SUPPLY CURRENT
I
V+(NS)
V+ Supply Current
V+ Supply Current After Startup
V
DD
Supply Current
V+ Shutdown Current
V
DD
Shutdown Current
PREREGULATOR/STARTUP
V+ Input Voltage
V
DD
Supply Voltage
INTERNAL REGULATORS (V
CC
)
V
CC
Output Voltage
V
CC
Undervoltage Lockout
OUTPUT DRIVER
Peak Source Current
Peak Sink Current
NRDV High-Side Driver
Resistance
NDRV Low Side Driver
Resistance
PWM COMPARATOR
OPTO Input Bias Current
OPTO Control Range
Slope Compensation
V
SCOMP
MAX5014
V
OPTO =
V
SS_SHDN
-1.00
2
26
1.00
3
µA
V
mV/µs
R
OH
R
OL
V
CC
= 11V, (externally forced)
V
CC
= 11V, (externally forced)
V
CC
= 11V, externally forced,
NDRV sourcing 50mA
V
CC
= 11V, externally forced,
NDRV sinking 50mA
570
1000
4
1.6
12
4
mA
mA
Ω
Ω
V
CC_UVLO
Powered from V+, I
CC
= 7.5mA, V
DD
= 0
Powered from V
DD
, I
CC
= 7.5mA
V
CC
falling
7.5
9.0
9.8
10.0
6.6
12
11.0
V
V
V
18
13
110
36
V
V
I
VDD(NS)
I
VDD(S)
I
V+(S)
V
DD
= 0, V+ = 110V, driver not switching
V+ = 110V, V
DD
= 0, V
OPTO
= 4V,
driver switching
V+ = 110V, V
DD
= 13V, V
OPTO
= 4V
V
DD
= 36V, driver not switching
V
DD
= 36V, driver switching, V
OPTO
= 4V
V
SS_SHDN
= 0, V+ = 110V
V
SS_SHDN
= 0
0.85
1.4
11
0.9
1.9
190
8
1.3
2.7
290
20
1.3
2.6
mA
µA
mA
µA
µA
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
2
_______________________________________________________________________________________
Current-Mode PWM Controllers with Integrated
Startup Circuit for Isolated Power Supplies
MAX5014/MAX5015
ELECTRICAL CHARACTERISTICS (continued)
(V
DD
= 13V, a 10µF capacitor connects V
CC
to GND, V
CS
= 0, V+ = 48V, 0.1µF capacitor connected to SS_SHDN, NDRV = open cir-
cuit, OPTO = GND, T
A
= -40°C to +85°C, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
THERMAL SHUTDOWN
Thermal Shutdown Temperature
Thermal Hysteresis
CURRENT LIMIT
CS Threshold Voltage
CS Input Bias Current
Current Limit Comparator
Propagation Delay
CS Blanking Time
OSCILLATOR
Clock Frequency Range
Max Duty Cycle
SOFT-START
SS Source Current
SS Sink Current
Peak Soft-Start Voltage Clamp
Shutdown Threshold
No external load
V
SS_SHDN
falling
V
SS_SHDN
rising
I
SSO
V
SS_SHDN
= 0
2.0
1.0
2.331
0.25
0.53
2.420
0.37
0.59
2.500
0.41
0.65
4.6
6.5
µA
mA
V
V
V
OPTO
= 4V
MAX5014, V
OPTO
= 4V
MAX5015, V
OPTO
= 4V
247
75
44
275
302
85
50
kHz
%
V
ILIM
V
OPTO
= 4V
0
≤
V
CS
≤
2V, V
OPTO
= 4V
25mV overdrive on CS, V
OPTO
= 4V
V
OPTO
= 4V
419
-1
180
70
465
510
1
mV
µA
ns
ns
150
25
°C
°C
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Typical Operating Characteristics
(V+ = 48V, V
DD
= 13V, NRDV is open circuit, T
A
= +25°C, unless otherwise noted.)
V
SS_SHDN
vs. TEMPERATURE
(AT THE END OF SOFT-START)
MAX5014 toc01
NDRV FREQUENCY vs.
TEMPERATURE
MAX5014 toc02
MAX5014 MAXIMUM DUTY CYCLE
vs. TEMPERATURE
V
OPTO
= 4V, CS = GND
MAXIMUM DUTY CYCLE (%)
80.9
80.8
80.7
80.6
80.5
80.4
MAX5014 toc03
1.003
V
SS_SHDN
(V) (NORMALIZED TO V
REF
= 2.4V)
OPTO = CS = GND
1.002
278
81.0
277
NDRV FREQUENCY (kHz)
V
OPTO
= 4V, CS = GND
276
1.001
275
1.000
274
0.999
-40
-20
0
20
40
60
80
TEMPERATURE (°C)
273
-40
-20
0
20
40
60
80
TEMPERATURE (°C)
-40
-20
0
20
40
60
80
TEMPERATURE (°C)
_______________________________________________________________________________________
3
Current-Mode PWM Controllers with Integrated
Startup Circuit for Isolated Power Supplies
MAX5014/MAX5015
Typical Operating Characteristics (continued)
(V+ = 48V, V
DD
= 13V, NRDV is open circuit, T
A
= +25°C, unless otherwise noted.)
MAX5015 MAXIMUM DUTY CYCLE
vs. TEMPERATURE
MAX5014 toc04
V+ SUPPLY CURRENT
vs. TEMPERATURE
MAX5014 toc05
SOFT-START SOURCE CURRENT
vs. TEMPERATURE
SOFT-START SOURCE CURRENT (µA)
4.95
4.90
4.85
4.80
4.75
4.70
4.65
4.60
4.55
4.50
V
DD
= 0, V+ = 110V, OPTO =
CS = SS_SHDN = GND
MAX5014 toc06
48.0
47.8
MAX DUTY CYCLE (%)
V
OPTO
= 4V, CS = GND
47.6
47.4
47.2
47.0
46.8
-40
-20
0
20
40
60
80
TEMPERATURE (°C)
1.46
1.45
V+ INPUT CURRENT (mA)
1.44
V
OPTO
= 4V, V
DD
= CS = GND
1.43
1.42
1.41
1.40
1.39
1.38
-40
-20
40
TEMPERATURE (°C)
0
20
60
80
5.00
-40
-20
0
20
40
60
80
TEMPERATURE (°C)
V+ INPUT CURRENT vs.
TEMPERATURE (AFTER STARTUP)
MAX5014 toc07
V+ SHUTDOWN CURRENT
vs. TEMPERATURE
194
V+ SHUTDOWN CURRENT (µA)
193
192
191
190
189
188
187
186
MAX5014 toc08
CS THRESHOLD VOLTAGE
vs. TEMPERATURE
MAX5014 toc09
11.25
195
V+ = 110V, OPTO = SS_SHDN =
CS = GND, V
DD
= 13V
0.488
11.20
V+ INPUT CURRENT (µA)
CS THRESHOLD VOLTAGE (V)
0.487
V
OPTO
= 4V, V+ = 110V
0.486
11.15
V+ = 110V, V
OPTO
= 4V,
CS = GND, V
DD
= 13V
11.10
0.485
11.05
0.484
11.00
-40
-20
0
20
40
60
80
TEMPERATURE (°C)
185
-40
-20
0
20
40
60
80
TEMPERATURE (°C)
0.483
-40
-20
0
20
40
60
80
TEMPERATURE (°C)
NDRV RESISTANCE
vs. TEMPERATURE
MAX5014 toc10
CURRENT-LIMIT DELAY
vs. TEMPERATURE
MAX5014 toc11
V
SS_SHDN
vs. V
DD
MAX5014 toc12
5.0
4.5
NDRV RESISTANCE (Ω)
4.0
HIGH-SIDE DRIVER
3.5
3.0
2.5
2.0
1.5
1.0
-40
-20
40
TEMPERATURE (°C)
0
20
60
80
LOW-SIDE DRIVER
190
188
CURRENT LIMIT DELAY (ns)
186
184
182
180
178
176
174
172
170
-40
-20
0
20
40
60
80
TEMPERATURE (°C)
V
OPTO
= 4V, 100mV OVERDRIVE ON CS
2.410
2.408
V
SS_SHDN
(V)
2.406
2.404
2.402
2.400
0
5
10
15
20
V
DD
(V)
25
30
35
40
4
_______________________________________________________________________________________
Current-Mode PWM Controllers with Integrated
Startup Circuit for Isolated Power Supplies
Typical Operating Characteristics (continued)
(V+ = 48V, V
DD
= 13V, NRDV is open circuit, T
A
= +25°C, unless otherwise noted.)
MAX5015 MAXIMUM DUTY
CYCLE vs. V
DD
MAX5014 toc13
MAX5014 toc14
MAX5014/MAX5015
NDRV FREQUENCY vs. V
DD
271.0
270.5
NDRV FREQUENCY (kHz)
270.0
269.5
269.0
268.5
268.0
267.5
267.0
0
5
10
15
20
V
DD
(V)
25
30
35
40
V
OPTO
= 4V, CS = GND
48.0
47.9
MAXIMUM DUTY CYCLE (%)
47.8
47.7
V
CC
vs. V
DD
MAX5014 toc15
10.2
10.1
10.0
V
CC
(V)
9.9
9.8
9.7
V
OPTO
= 4V, CS = GND
DEVICE POWERED FROM V
DD
47.6
47.5
47.4
47.3
47.2
47.1
47.0
0
5
10
15
20
V
DD
(V)
25
30
35
40
DRIVER POWERED
FROM V+
DRIVER POWERED
FROM V
DD
9.6
9.5
0
5
10
DEVICE POWERED
FROM V+
15
20
V
DD
(V)
25
30
35
40
V+ SUPPLY CURRENT vs.
V+ VOLTAGE
1.39
V+ SUPPLY CURRENT (mA)
1.38
1.37
1.36
1.35
1.34
1.33
2
1.32
1.31
0
20
40
60
80
100
V+ VOLTAGE (V)
0
V
OPTO
= 4V, CS = GND, V
DD
= 0
MAX5014 toc16
V+ INPUT CURRENT vs. VOLTAGE
(AFTER STARTUP)
MAX5014 toc17
1.40
12
10
V+ INPUT CURRENT (µA)
V
OPTO
= 4V, CS = GND, V
DD
= 13V
8
6
4
0 10 20 30 40 50 60 70 80 90 100 110
V+ VOLTAGE (V)
V
CC
VOLTAGE vs. V
CC
CURRENT
MAX5014 toc18
V
CC
VOLTAGE vs. V
CC
CURRENT
9.9
9.8
V
CC
VOLTAGE (V)
9.7
9.6
9.5
9.4
9.3
9.2
V+ = 36V
V+ = 24V
V
DD
= OPTO = CS = GND
V+ = 110V
V+ = 90V
V+ = 72V
V+ = 48V
MAX5014 toc19
10.4
V+ = 110V, OPTO = CS = GND
10.2
V
DD
= 36V
V
CC
VOLTAGE (V)
10.0
9.8
V
DD
= 13V
9.6
9.4
9.2
9.0
0
5.0
10.0
15.0
V
CC
CURRENT (mA)
10.0
9.1
9.0
20.0
0
5.0
10.0
V
CC
CURRENT (mA)
15.0
20.0
_______________________________________________________________________________________
5
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