APW38HC42A/3A/4A/5A
CMOS Current-Mode PWM Voltage Controller
Features
•
•
•
•
•
•
•
•
•
•
•
Ultralow start-up current (25µA typical)
Low operating current (2mA typical)
Fast output rise/fall times :
General Description
The APW38HC4XA family are fixed frequency, high
performance, current-mode PWM controller with 1.2
A drive current capability. Undervoltage lockout cir-
cuitry allows the APW38HC42A and APW38HC44A
versions to start up at 14.5V and operate down to
9V, and the APW38HC43A and APW38HC45A ver-
sions start at 8.4V with operateion down to 7.6V. All
versions operate up to 24V. The ultra low start-up
current 25µA (typical), and operating current 2mA
(typical) have been designed to improve the converter
efficiency. High output driving capability up to 1.2A
ensures the fast switching to minimize the switching
losses. The APW38HC4XA features a trimmed and
temperature compensated oscillator discharge cur-
rent and bandgap reference. APW38HC4XA is avail-
able in both 8-pin plastic DIP and SOP packages.
−
15ns rise/10ns fall
High output drive (1.2A peak current)
CMOS outputs with rail-to-rail swing
Current-mode operation up to 1MHz
Trimmed 5V bandgap reference
Pin-to-pin compatible with MIC38HC4X
Trimmed oscillator discharge current
UVLO with hysteresis
Low cross-conduction currents
Applications
•
•
•
Current-mode , Off-line , Switched-mode Power
Supplies
Current-mode , DC-to-DC converters
Various converters ( step-down, step-up, flyback
, forward, and synchronous FET)
Pin Description
COMP
FB
ISNS
RT/CT
1
2
3
4
8
7
6
5
VREF
VDD
OUT
GND
Ordering and Marking Information
APW 38HC4XA
Lead Free Code
Handling Code
Temp. Range
Package Code
Package Code
J : DIP - 8
K : SOP-8
Temp. Range
C : 0 to 70
°
C
I : -40 to 85
°
C
Handling Code
TU : Tube
TR : Tape & Reel
Lead Free Code
L : Lead Free Device
Blank : Original Device
X - 2/3/4/5
XXXXX - Date Code
APW 384XA J :
APW 38HC4XA
XXXXX
APW 38HC4XA
X - 2/3/4/5
XXXXX - Date Code
APW 384XA K :
XXXXX
ANPEC reserves the right to make changes to improve reliability or manufacturability without notice, and advise
customers to obtain the latest version of relevant information to verify before placing orders.
Copyright
ANPEC Electronics Corp.
Rev. A.7 - Jan., 2003
1
www.anpec.com.tw
APW38HC42A/3A/4A/5A
Selection Guide
Duty Cycle
0~96%
0~50%
Startup 8.4V
Minimum Operating 7.6V
APW38HC43A
APW38HC45A
Startup 14.5V
Minimum Operating 9V
APW38HC42A
APW38HC44A
Block Diagram
VDD
5V
Reference
VREF
UVLO
RT/CT
Oscillator
OUT
T
Q
FB
2.5V
-
E. A.
2R
-
R
S
Q
R
+
+
COMP
GND
ISNS
Functional Pin Description
Pin Name
1
2
3
4
5
6
7
8
Pin Number
COMP
FB
ISNS
RT/CT
GND
OUT
VDD
VREF
Function Description
Compensation: Connect external compensation network to
modify the error amplifier output.
Feedback (Input): Error amplifier input. Feedback is 2.5V at
desired output voltage.
Current Sense (Input): Current sense comparator input.
Connect to current sensing resistor or current transformer.
Timing Resistor/Timing Capacitor: Connect external RC
network to select switching frequency.
Ground: Combined analog and power ground.
Power Output: Totem-pole output.
Analog Supply (Input): Controller circuitry supply input. Return
to analog ground (AGND).
5V Reference (Output): Connect external RC network.
2
www.anpec.com.tw
Copyright
ANPEC Electronics Corp.
Rev. A.7 - Jan., 2003
APW38HC42A/3A/4A/5A
Absolute Maximum Ratings
Symbol
V
DD
V
ISNS
V
FB
T
J
T
STG
T
SDR
V
ESD
Supply Voltage
Current Sense Voltage
Feedback Voltage
Junction Temperature Range
Storage Temperature
Soldering Temperature
Minimum ESD Rating
Parameter
Rating
24
-0.3 to 5.5
-0.3 to 5.5
300
-65 to 150
300,10 Seconds
±3
Unit
V
V
V
°C
°C
°C
kV
Thermal Characteristics
Symbol
θ
JA
Parameter
Thermal Resistance in Free Air
DIP
SOP
Value
125
175
Unit
°C/W
Electrical Characteristics
V
DD
=15V, Note3 ; RT=9.09KΩ; CT=3.3nF; -40
o
C
≤
T
A
≤
85
o
C; unless noted
Symbol
Parameter
Test Conditions
T
A
=25°C, I
O
(Output Current)=1mA
12V≤ V
DD
≤
18V, I
O
=5µA
1mA≤ I
O
≤
20mA
Line, Load, Temp.
10Hz≤ f
≤10kHz,
T
A
= 25
o
C
T
A
= 125
o
C, 1000 hrs
APW38HC4XA
Min.
Typ. Max.
4.90
5.00
1
6
0.2
50
5
-55
52
0.2
0.03
8.4
8.4
1.6
2.50
5.10
20
25
5.18
25
-120
55
1.0
9.0
9.5
Unit
V
mV
mV
mV/°C
V
µV
mV
mA
kHz
%
%/°C
mA
V
P-P
2.58
V
REFERENCE VOLTAGE
V
REF
Reference Voltage
REG
line
Line Regulation
REG
load
Load Regulation
Temp. Stability
Total Output Variation
Output Noise Voltage
Long Term Stability
I
SC
Output Short Circuit
OSCILLATOR
F
OSC
Initial Accuracy
Voltage Stability
Temp. Stability
I
DISCHG
Clock Ramp Reset
Current
4.82
-25
T
A
=25°C, Note 4
12V≤ V
DD
≤
18V
T
MIN
≤
T
A
≤
T
MAX
T
A
=25°C, V
RT/CT
=2V
T
A
=T
MIN
to T
MAX
V
RT/CT
peak to peak
V
COMP
=2.5V
3
49
7.7
7.2
V
OSC
Amplitude
ERROR AMPLIFIER
Input Voltage
Copyright
ANPEC Electronics Corp.
Rev. A.7 - Jan., 2003
2.42
www.anpec.com.tw
APW38HC42A/3A/4A/5A
Electrical Characteristics (Cont.)
V
DD
=15V, Note3 ; RT=9.09KΩ; CT=3.3nF; -40
o
C
≤
T
A
≤
85
o
C; unless noted
Symbol
ERROR
I
FB
A
VOL
BW
Parameter
Test Conditions
V
FB
=5V
2≤ V
O
≤
4V
12≤ V
DD
≤
18V
V
FB
=2.7V, V
COMP
=1.1V
V
FB
=2.3V, V
COMP
=5V
V
FB
=2.3V, R
L
=15k to GND
V
FB
=2.7V, R
L
=15k to VREF
Notes 1,2
V
COMP
=5V, Note 1
12≤ V
DD
≤
18V, Note 1
V
ISNS
=5V
60
0.7
60
2
-0.5
5
70
1.0
7
-1
5.4
0.01
3.0
1.0
70
120
Sourcing Current = 200mA
Sinking Current = 200mA
T
A
=25°C, C
L
=1nF
T
A
=25°C, C
L
=1nF
APW38HC42/4A 13.5
APW38HC43/5A 7.8
APW38HC42/4A 8.0
APW38HC43/5A 7.0
APW38HC42/3A
APW38HC44/5A
94
46
6.3
4
15
10
14.5
8.4
9.0
7.6
96
50
0
30
25
2.0
150
150
4.0
30
20
15.5
9.0
10.0
8.2
APW38HC4XA
Min.
Typ.
Max.
0.1
Unit
µA
dB
MHz
dB
mA
mA
V
V
V/V
V
dB
µA
ns
Ω
ns
ns
V
V
AMPLIFIER
Input Bias Current
Open Loop Gain
Unity Gain Bandwidth
PSRR
Output Sink Current
Output Source Current
V
OH
Output Voltage (High)
V
OL
Output Voltage (Low)
CURRENT SENSE
A
Gain
V
THM
Maximum Threshold
PSRR
I
ISNS
Input Bias Current
T
D
Delay to Output
OUTPUT
R
DS(ON)
High
R
DS(ON)
Low
t
R
Rise Time
t
F
Fall Time
UNDERVOLTAGE LOCKOUT
V
DD(ST)
Start Threshold
V
DD(MIN)
Minimum Operating Voltage
PULSE WIDTH MODULATOR
D
MAX
D
MIN
Maximum Duty Cycle
Minimum Duty Cycle
1.1
3.15
1.1
0.1
250
2.85
0.9
%
%
TOTAL STANDBY CURRENT
V
DD
=13V, APW38HC42/4A
V
DD
=7.5V, APW38HC43/5A
I
DD(OP)
Operating Supply Current
V
FB
=V
ISNS
= 0V, C
L
=1nF
Note 1 : Parameter measured at trip point of latch with V
FB
=0V.
I
DD(ST)
Start-Up Current
µA
mA
Note 2 : Gain defined as :
A=
∆V
COMP
, 0<V
TH(ISNS)
<0.8V
∆V
TH(ISNS)
Note 3 : Adjust V
DD
above the start threshold before setting at 15V.
Note 4 : Output frequency equals oscillator frequency for the APW38HC42A and APW38HC43A. Output
frequency for APW38HC44A and APW38HC45A equals one half of the oscillator frequency.
Copyright
ANPEC Electronics Corp.
Rev. A.7 - Jan., 2003
4
www.anpec.com.tw
APW38HC42A/3A/4A/5A
Typical Characteristics
Oscillator Frequency Configuration
100
Output Dead Time vs. Oscillator Frequency
100
RT Resistance (kΩ)
Output Dead Time ( %)
20
F
0p
47
0p
F
1n
F
10nF
4.7nF
10
7n
4.
F
nF
10
10
1.8nF
8n
1.
F
200pF
470pF
1nF
1
10
100
1000
1
10
100
1000
Oscillator Frequency (kHz)
Oscillator Frequency (kHz)
Oscillator Discharge Current vs.
Temperature
Oscillator Discharge Current (mA)
8.8
8.6
8.4
8.2
8.0
7.8
7.6
7.4
7.2
7.0
-60
-30
0
30
60
90
120
150
Current Sense Amplifier Threshold vs.
Error Amplifier Output
Current Sense AMP Threshold (V)
1.2
1.0
0.8
0.6
0.4
0.2
0.0
0
1
2
3
4
5
6
7
-50
o
C
25
o
C
125
o
C
9.0
V
DD
= 15V
V
RTCT
= 2V
Temperature (°C)
Error Amplifier Output (V)
Copyright
ANPEC Electronics Corp.
Rev. A.7 - Jan., 2003
5
www.anpec.com.tw
