ELM652DA Dual-channeling CV/CC mode 36V switching controller

ELM652DA Dual-channeling CV/CC mode 36V switching controller
■General description
ELM652DA is a dual-channeling CV/CC mode switching regulator. ELM652DA is designed to allow for
operating a wide supply voltage range from 8V to 36V.
ELM652DA features a dual-channeling CV/CC mode control functions, the CV mode (Constant voltage)
function to provide a regulated voltage output and the dual-channeling CC mode (Constant current) function
provides dual-channeling current limitation function, it is suitable for the DC / DC switching power applications
when requested the dual-channeling current limitation function.
■Features
■Application
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
UVLO protection
Dual-channeling CV/CC mode control
Soft start function for start-up
Output over-voltage protection
Over temperature protection
Fold back short-circuit protection
High efficiency operation
Synchronization rectification
Input voltage range
: 8V to 36V
Fixed operating frequency
: 100kHz
Voltage reference accuracy
: 5.0V±1%
Current limit accuracy
: ±4%
Package
: SOP-8
Car charger(USB. 2ch)
Automotive power applications
DC/DC converters with current limited
General purpose CV/CC power supply
■Maximum absolute ratings
Parameter
VCC to GND
PDRV to VCC
NDRV to VCC
VOUT to GND
CS1 to GND
CS2 to GND
COMP to GND
Power dissipation at Ta <60 °C
Operating temperature
Storage temperature range
Symbol
Vcc
PDRV
NDRV
Vout
CS1
CS2
COMP
Pd
Top
Tstg
Limit
-0.3 to +40.0
+0.3 to -40.0
+0.3 to -40.0
-0.3 to +7.0
-0.3 to +7.0
-0.3 to +7.0
-0.3 to +7.0
0.75
-40 to +85
-60 to 150
Caution:Permanent damage to the device may occur when ratings above maximum absolute ones are used.
8-1
Unit
V
V
V
V
V
V
V
W
°C
°C
Rev.1.1
ELM652DA Dual-channeling CV/CC mode 36V switching controller
■Selection guide
ELM652DA-N
Symbol
a
b
c
Package
Product version
Taping direction
ELM652DA - N
↑↑ ↑
ab c
D: SOP-8
A
N: Refer to PKG file
* Taping direction is one way.
■Pin configuration
SOP-8(TOP VIEW)
1
8
2
7
3
6
4
5
Pin No.
1
2
3
4
5
6
7
8
Pin name
GND
CS1
CS2
PDRV
NDRV
VCC
VOUT
COMP
Pin description
Graund
1st channel current sense input
2Nd channel current sense input
PMOSFET driver output
NMOSFET driver output
The input supply voltage
The output voltage regulation feedback
The E/A output pin for compensation
■Standard circuit
Q1
U
6
Vin
8
C1
+
5
R1
C2
1
C3
VCC
PDRV
COMP
CS1
NDRV
CS2
GND
L
4
Vout
2
3
C4
VOUT 7
R2
ELM652DA
Q2
8-2
R3
GND1
GND2
Rev.1.1
ELM652DA Dual-channeling CV/CC mode 36V switching controller
■Block diagram
COMP
8
VOUT
6
5.8V
PDRV
VCC
7
Reference
Generator
+
4
OTP
RAMP
5.1V
+
Error
+ Amp.
-
-
Control
logic
PWM
Comp.
NGate
DRV
Soft start
+
Current
Amp.
2.0V
Vss
-
PGate
DRV
+
112mV
+
1
3
2
5
GND
CS2
CS1
NDRV
■Functional descriptions
1. Dual-channeling CV/CC mode control
ELM652DA provides dual channeling CV/CC function. The CV (constant voltage) function is implemented to
deliver a regulated output voltage for the output terminal, and the dual-channeling CC (constant current) function is to limit dual-port output current to be a limited value to prevent the device damaged due to output short
circuit or over current condition.
2. Soft Start function
ELM652DA is composed of built-in internal soft start function to prevent a large surge current happening
when during start-up period due to the surge current charging output filter capacitors.
3. Output over-voltage protection
ELM652DA provides built-in output over-voltage protection function. When output over-voltage happens, the
ELM652DA shuts down and recovers to normal state automatically if output over-voltage is released.
4. Output short-circuit protection
ELM652DA provides output short-circuit protection function. When output short happens, the ELM652DA
shuts down and recovers to normal state automatically if output short-circuit is released.
8-3
Rev.1.1
ELM652DA Dual-channeling CV/CC mode 36V switching controller
■Electrical characteristics
Parameter
Input voltage section
Input voltage
Input no load current
Oscillator section
Operating frequency
Duty cycle range
Error amplifier section
Reference voltage of
the voltage error amplifier
Reference voltage of
the current error amplifier
Symbol
Vin=12V, Iout=4.0A, Top=25°C, unless otherwise specified
Condition
Min.
Typ.
Max. Unit
Vin
Ino-load Iout=0A
Tran conductance of Error amplifier
Fosc
Duty
Vout
Iout=0A
Vcs1
Vcs2
8
36
10
V
mA
85
115
95
kHz
%
5.05
5.10
5.15
V
107.5
112.0
116.5
mV
Gmerr
150
µA/V
5.8
V
2.0
V
150
100
°C
°C
Output over voltage protection section
Output over voltage protection
Vovp
Output short circuit protection section
Short circuit fold back voltage
Over temperature protection section
Thermal shut-down temperature
Vscp
Totp,r
Totp,f
Temperature rising
Temperature falling
■Marking
SOP-8
Mark
652
a to o
8-4
Content
Product No.code
Assembly lot No.
Rev.1.1
ELM652DA Dual-channeling CV/CC mode 36V switching controller
■Application notes
1. CC current setting
The constant current value of ELM652DA is set by R2 resistor and R3 resistor. The output current of CC mode
and these resistors are set by the following equations:
R2 = 0.112 / IC1
R3 = 0.112 / IC2
2. Input capacitor selection
The bulk input capacitor selection is based on the voltage rating, the RMS current carrying capability, and the
required input voltage ripple.
The capacitor voltage rating is recommended with 1.5 times for the maximum input voltage as conservative
guideline, depending on the application condition.
The capacitor RMS current rating is considered for stress condition, and the trapezoid current waveform as the
simplified formula is described:
Irms = Iout(max) * √ ( Vout / Vin )
Vin = input voltage ; Vout = output voltage ; Iout(max) = maximum output current.
The capacitor values with respect to the required input voltage ripple if neglect ESR is described:
C = Iout(max) * ΔT / ΔV
ΔT = capacitor supplied charging time ; ΔV = allowable input voltage ripple.
3. Output inductor selection
The output inductor is selected for the trade-offs between the output inductor current ripple, dc resistance for
power loss, load transient response time, and the physical size.
The output inductor current ripple determines the output voltage ripple requirement, and the inductor’s dc resistance concerns the power loss. The larger the inductor value, the smaller the inductor ripple current, but the
slower the transient response time, the larger the inductor dc resistance, and hence the larger the power loss.
The inductance value is described:
L = Vout * ( 1 - Vout / Vin ) * Tsw / ΔLl
Vin = input voltage ; Vout = output voltage ;
Tsw = switching period ; ΔLl = inductor ripple current.
4. Output capacitor selection
The output capacitor is selected for the trade-offs between output ripple voltage requirement, the output voltage
rating, the RMS current rating, the ESR and ESL for the load transient, and the physical size.
The capacitor voltage rating is recommended with 1.5 times for the maximum output voltage as conservative
guideline.
The capacitor RMS current rating is considered for stress condition’ and the trapezoid current waveform as the
simplified formula is described:
Irms = ΔLl / 2√3 ; ΔLl = inductor ripple current.
The output ripple voltage with respect to the capacitor ESR is described:
ΔV = ΔI * ( ESR + Tsw / ( 8 * C ) )
ΔI = capacitor ripple current’ which is equivalent to the inductor ripple current ;
ESR = capacitor equivalent series resistance ; Tsw = switching period.
8-5
Rev.1.1
ELM652DA Dual-channeling CV/CC mode 36V switching controller
5. FET selection
The FET transistor is selected depend on the application specification.
When the input voltage is under 30V like 24V car battery, the following FET is recommended. ELM35603KA
is complementary power MOSFET.
N-ch:Vds= 40V, Id= 10.0A
P-ch:Vds=-40V, Id= -7.0A
When the input voltage is under 20V like 12V car battery, the following FET is recommended. ELM35604KA
is complementary power MOSFET.
N-ch:Vds= 30V, Id= 8.5A
P-ch:Vds=-30V, Id= -7.0A
8-6
Rev.1.1
ELM652DA Dual-channeling CV/CC mode 36V switching controller
■Typical characteristics
• Vin=12V, R1=100kΩ, R2=0.1Ω, R3=0.05Ω, NMOS=ELM33410CA, PMOS=ELM34401AA
L=100µH, C1=100µF, C2=47nF, C3=47pF, C4=220µF, Top=25°C
Iout-Vout
6.000
Iout-Efficiency
100.00
Vin=24V, Iload=2A
90.00
5.000
Vin=12V,
Iload=2A
Vin=12V,
Iload=1A
Efficiency (%)
Vout (V)
4.000
80.00
3.000
2.000
Vin=24V,
Iload=1A
1.000
0.000
0.000
60.00
50.00
40.00
30.00
Vin=12V,
Iload=1A Vin=24V,
Iload=2A
Vin=12V,
Iload=2A
Vin=24V,
Iload=1A
20.00
10.00
0.500
1.000 1.500
Iout (A)
Vin-Vout
5.20
2.000
0.00
0.000
2.500
0.500
1.000
1.500
2.000
2.500
Iout (A)
Vin-Freq
Iload=500mA
110.00
5.15
Iload=500mA
105.00
Freq (kHz)
Vout (V)
70.00
5.10
5.05
100.00
95.00
5.00
0
10
20
Vin (V)
Vin-Vcs
90.00
0
40
30
20
Vin (V)
Vin-Vout
Iload=1A
130
10
5.20
30
40
Iload=500mA
125
5.15
Vout (V)
Vcs1 (V)
120
115
5.10
110
5.05
105
100
0
5
10
15 20 25
Vin (V)
30
35
5.00
0
40
8-7
10
20
Vin (V)
30
40
Rev.1.1
ELM652DA Dual-channeling CV/CC mode 36V switching controller
Top-Freq
Top-Vcs
Iload=500mA
Iload=1A
120
115
Vcs (mV)
100.00
95.00
110
105
90.00
-30
0
30
Top (°C)
60
100
-30
90
0
60
30
Top (°C)
90
Top-Efficiency
Iload=500mA
95.00
Efficiency (%)
Freq (kHz)
105.00
90.00
85.00
80.00
-30
8-8
0
30
Top (°C)
60
90
Rev.1.1