Page 1
HI-SINCERITY
MICROELECTRONICS CORP.
Spec. No. : HP200202
Issued Date : 1998.08.01
Revised Date : 2002.12.03
Page No. : 1/10
H3842P / HSMC3842
HIGH PERFORMANCE CURRENT MODE CONTROLERS
Description
The H3842P/HSMC3842 are high performance fixed frequency current mode
controllers. They are specifically designed for Off-Line and DC To DC converter
applications offering the designer a cost-effective solution with minimal external
components. These integrated circuits feature a trimmed oscillator for precise duty
cycle control. A temperature compensa-ted reference, high gain error amplifier,
current sensing comparator, and a high current totem pole output ideally suited for
driving a power MOSFET. Also included are protective features consisting of input and reference undervoltage
lockouts each with hysteresis, cycle-by-cycle current limiting, programmable output deadtime, and a latch for single
pulse metering.
Features
• Trimmed Oscillator for Precise Frequency Control
• Oscillator Frequency Guaranteed at 250 kHz
• Current Mode Operation to 500 kHz
• Automatic Feed Forward Compensation
• Latching PWM for Cycle-By-Cycle Current Limiting
• Internally Trimmed Reference with Undervoltage Lockout
• High Current Totem Pole Output
• Undervoltage Lockout with Hysteresis
• Low Startup and Operating Current
DIP-8Pin
Absolute Maximum Ratings
Symbol Parameter Value Unit
Vi Supply Voltage (low impedance source) 30 V
Vi Supply Voltage (Ii<30mA) Self Limiting
Io Output Current
±1
Eo Output Energy (capacitive load) 5 uJ
Analog Inputs (pin 2, 3) -0.3 to 5.5 V
Error Amplifier Output Sink Current 10 mA
Ptot
Power Dissipation at Tamb≤25
o
C
1.25 W
Tstg Storage Temperature Range -65 to 150
TJ Junction Operating Temperature -40 to 150
TL Lead Temperature (soldering 10s) 300
Block Diagram
Vcc
Ground
RT/CT
VFB
COMP
Current
Sense
7
5
4
2
1
3
34V
Error AMP.
+
-
2.50V
UVLO
OSC
S/R
2R
5V
REF
R
VREF Good
Logic
1V
Comparator
Current
Sense
Internal
Bias
T
S
R
PWM Latch
8
6
VREF
5V 50mA
Output
A
o
C
o
C
o
C
H3842P HSMC Product Specification
Page 2
HI-SINCERITY
MICROELECTRONICS CORP.
Pin Connection (Top View)
DIP-8P Function Description
This pin is the Error Amplifier output and is made available for
loop compensation.
This is the inverting input of the Error Amplifier. It’s normally
connected to the switching power supply output through a
resistor divider.
A voltage proportional to inductor current is connected to this
input. The PWM uses this information to terminate the output
switch conduction.
The oscillator frequency and maximum output duty cycle are
programmed by connecting resistor RT to Vref and cpacitor CT
to ground. Operation to 500kHz is possible.
This output directly drives the gate of a power MOSFET. Peak
currents up to 1A are sourced and sunk by this pin.
This is the reference output. It provides charging current for
capacitor CT through resistor RT.
5678
1234
Pin1: Compensation
Pin2: Voltage Feedback
Pin3: Current Sense
Pin4: RT/CT
Pin5: Ground This pin is the combined control circuitry and power ground.
Pin6: Output
Pin7: Vcc This pin is the positive supply of the control IC.
Pin8: Vref
Spec. No. : HP200202
Issued Date : 1998.08.01
Revised Date : 2002.12.03
Page No. : 2/10
Thermal Data
Symbol Description Max. Units
Rth j-amb Thermal Resistance Junction-ambient 100
Electrical Specifications
Parameter Test Conditions Min. Typ. Max. Units
Under-Voltage Lockout Sect ion
Start Threshold 14.5 16 17.5 V
Min. Operating Voltage After Turn On 8.5 10 11.5 V
Electrical Characteristics
Unless otherwise stated, specifications apply for 0≤Ta≤70°C Vcc =15V (Note 1); RT=680Ω, CT=0.022uF for
triangular mode, RT=10k, CT=3.3nf for sawtooth mode
Parameter Test Conditions Min. Typ. Max. Units
Reference Section
Reference Output Voltage
Line Regulation
Load Regulation
Temperature. Stability
Total Output Variation Line , Load , Temp (Note 2) 4.82 - 5.18 V
Output Noise Voltage
Long Term Stability
Output Short current
Oscillator Section
Frequency
Frequency Chnge with Temperature
Frequency Change with Temperature
Oscillator Voltage Swing Peak to Peak - 1.7 - V
Discharge Current
Tj=25°C,Io=1mA
12V≤Vin≤25V
1mA≤Io≤20mA
(Note 2)
10Hz≤f≤10kHz,Tj=25°C
Ta=125°C,1000Hrs
Ta=25°C
Tj=25°C
Tlow≤Ta≤Thigh
12V≤Vcc≤25V
Tlow≤Ta≤Thigh (Note 2)
Tj=25°C
Tj=25°C
Tlow≤Ta≤Thigh
(Note 2)
(Note 2)
4.90 5 5.1 V
-2.020mV
-3.025mV
-0.2-
-50- uV
-5-mV
-30 -100 -180 mA
47 52 57 KHz
46 52 60 KHz
-0.21 %
-5-%
-0.5- %
7.8 8.3 9.3 mA
7.2 - 9.5 mA
mV/°C
o
C/W
H3842P HSMC Product Specification
Page 3
HI-SINCERITY
MICROELECTRONICS CORP.
Spec. No. : HP200202
Issued Date : 1998.08.01
Revised Date : 2002.12.03
Page No. : 3/10
Parameter Test Conditions Min. Typ. Max. Units
Error Amplifier Section
Voltage Feedback Input Vo=2.5V 2.42 2.50 2.58 V
Input Bias Current VFB=5.0V - -0.1 -2.0 uA
Open Loop Voltage Gain
Unity Gain Bandwidth
Power Supply Rejection Ratio
Output Current
Output Voltage Swing
High State
2≤Vo≤4 V
Tj=25°C
(Note 2)
12V≤Vcc≤25V
Sink (Vo=1.1V, VFB=2.7V) 2.0 12 - mA
Source (Vo=5.0V, VFB=2.3V) -0.5 -1.0 - mA
VFB=2.3V, RL=15K to ground 5 6 - V
65 90 - dB
0.7 1.0 - MHz
60 70 - dB
Low State VFB=2.7V, RL=15K to Vref - 0.7 1.1 V
Current Sense Section
Current Sense Input Voltage Gain
Maximum Current Sense Input
Thresold
Ppwer Supply Rejection Ratio
(Notes 3 & 4)
(Note 3)
12V≤Vcc≤25V
(Note 3)
2.85 3.0 3.15 V/V
0.9 1.0 1.1 V
-70- dB
Input Bias Current - -2.0 -10 uA
Propagation Delay
Tj=25°C
(Note 2)
- 150 300 nS
Output Section
Low State (Isink=20mA) - 0.1 0.4 V
Output Voltage
Low State (Isink=200mA) - 1.5 2.2 V
High State (Isource=20mA) 13 13.5 - V
High State (Isource=200mA) 12 13.4 - V
Output Voltage Rise Time
Output Voltage Fall Time
Tj=25°C, CL=1.0nF
Tj=25°C, CL=1.0nF
(Note 2)
(Note 2)
- 50 150 nS
- 50 150 nS
Output Voltage with UVLO Activated Vcc=6V , Isink=1.0mA - -0.1 -1.1 V
Total Device
Start-Up Current - 0.1 0.5 mA
Operating Supply Current Vpin2=Vpin3=0, RT=10K, CT=3.3nF - 11 17 mA
Vcc Zener Voltage Icc=25 mA - 34 - V
Note 1: Adjust Vcc above the start threshold before setting at 15V.
Note 2: These parameters, although guaranteed are not 100% tested in production.
Note 3: Parameter measured at trip point of latch with Vpin2=0.
Note 4: Gain defined as: A=Vpin1/Vpin3, 0≤Vpin3≤0.8V
H3842P HSMC Product Specification
Page 4
HI-SINCERITY
MICROELECTRONICS CORP.
Characteristics Curve
Spec. No. : HP200202
Issued Date : 1998.08.01
Revised Date : 2002.12.03
Page No. : 4/10
10000K
1000K
fo(Hz)
8.5
Oscillator Frequency & Timing Resistance
CT=1.0nF
CT=2.2nF
CT=4.7nF
100K
10K
1K
100 1000 10000 100000
Oscillator Discharge Current & Temperate
9
RT(Ω)
Vi=15V
Vosc=2V
100
fo(Hz)
Maximum Duty Cycle & Timing Resistance
80
60
40
20
0
100 1000 10000 100000
RT(Ω)
Error Amp Open-Loop Gain and Phase &
Frequency
100
Vcc=15V
80
Gain
60
Vo=2V to 4V
L
=100K
R
o
C
Ta=25
Φ
30
60
8
Idischg (mA)
7.5
7
-50 -25 0 25 50 75 100 125
TA (oC)
Current Sense Input Threshold & Error Amp
Output Voltage
1.2
1
0.8
0.6
Vth (V)
0.4
0.2
Ta=25oC
Ta=125oC Ta=-40oC
Vcc=15V
40
(dB)
20
0
-20
10 100 1000 10000 100000 1000000 10000000
f (Hz)
Phase
Reference Voltage Change & Source Current
60
50
40
30
20
10
Ta=125oC Ta=25oC Ta=-40oC
Vcc=15V
90
120
150
180
0
02468
Vo (V)
0
0 20 40 60 80 100 120
Ire f (m A )
H3842P HSMC Product Specification
Page 5
HI-SINCERITY
MICROELECTRONICS CORP.
Spec. No. : HP200202
Issued Date : 1998.08.01
Revised Date : 2002.12.03
Page No. : 5/10
Reference Short Circuit Current &Temperature
110
100
90
80
Isc (mA)
70
60
50
-50 -25 0 25 50 75 100 125
Output Saturation Voltage & Load Current
0
-1
Ta=25oC
-2
Vsat (V)
Ta=-40oC
TA (oC)
Source Saturation
(Load to Ground)
Vcc=15V
0.1Ω
RL
≤
25
20
15
Ii (mA )
10
5
0
0 10203040
Supply Current & Supply Voltage
RT=10K
T
=3.3nF
C
Vi (V)
Output Saturation Voltage & Load Current
4
Sink Saturation
3
Ta=-40oC
2
Vsat (V)
(Load to Vcc)
Ta=25oC
-3
-4
0 200 400 600 800
Io (m A )
Vcc=15V
80us Puls ed Load
120Hz Rate
1
0
0 200 400 600 800
Io (m A )
Vcc=15V
80us Puls ed Load
120Hz Rate
H3842P HSMC Product Specification
Page 6
HI-SINCERITY
g
p
MICROELECTRONICS CORP.
Application Information
Open Loop Test Circuit
Spec. No. : HP200202
Issued Date : 1998.08.01
Revised Date : 2002.12.03
Page No. : 6/10
Vref
Error Amp.
Adjust
4.7KΩ
1KΩ
4.7KΩ
HPN2222A
100KΩ
I
Adjust
SENSE
5KΩ
RT
COMP
SENSE
I
RT/CT
REF
V
8
1
FB
V
2
H3842
3
4
CT
7
6
5
Vcc
Output
Ground
0.1uF
0.1uF
A
1W
1KΩ
Vcc
Output
Ground
High peak currents associated with capacitive loads necessitate careful grounding techniques. Timing and
bypass capacitors should be connected close to pin5 in a single point ground. The transistor and 5KΩ
otentiometerare used to samplethe oscillator waveform and apply an adjustable ramp to pin3.
Oscillator and Output Waveforms
Vcc
7
8
PWM
RT
4
Id
Clock
Oscillator
5V REG
1
2
CT
6
3
Output
Output
Large RT / Small CT
CT
CT
5
GND
Output
Error Amp Configuration Under Voltage Lockout
2.5V
+
V
2
Zi
Zf
FB
COMP
-
1
1mA
Vi
ON/OFF Command
7
To Rest Of IC
Von
Voff
H3842
16V
10V
Small RT / Lar
<17mA
<0.5mA
e CT
Icc
Voff Von
Vcc
H3842P HSMC Product Specification
Page 7
Current Sense Circuit
HI-SINCERITY
MICROELECTRONICS CORP.
Spec. No. : HP200202
Issued Date : 1998.08.01
Revised Date : 2002.12.03
Page No. : 7/10
Error Ampl.
COMP
Is
R
Rs C
Current
Sense
1
3
5
GND
Peak current (Is) is determined by the formula
Is(max.) ≈ 1V/Rs
A small RC filter may be required to suppress switch transients.
Slope Compensation Techniques
REG
V
8
RT
Is
Rs
SLOPE
R
R1
RT/CT
CT
SENSE
I
4
H3842
3
5
GND
2R
R1V
RT
RT/CT
Is
CT
Rs
R
R1
SLOPE
V
SENSE
I
REG
Current
Sense
Comparator
8
4
H3842
3
5
GND
Isolated MOSFET Drive and Current Transformer Sensing
Q1
Vin
VGS Waveforms
+
0
50%DC 25%DC
Ipk=((Vpin1-1.4)/3Rs)(Ns/Np)
+
0
-
Vcc
7
5.0Vref
+
-
+
COMP/Latch
H3842P HSMC Product Specification
+
-
6
S
Q
R
3
Isolation
Boundary
R
Rs Ns Np
C
Page 8
HI-SINCERITY
+
p
MICROELECTRONICS CORP.
Spec. No. : HP200202
Issued Date : 1998.08.01
Revised Date : 2002.12.03
Page No. : 8/10
Latched Shutdown
Error Amplifier Compensation
From Vo
Ri
Rd RfCf
From Vo
Rp
Cp
Ri
Rd
RfCf
2.5V
2
1
2.5V
2
1
2N3905
+
-
+
-
EA
EA
2N3903
4
8
R
R
+
2
-
1
EA
OSC
BIAS
+
1mA
2R
R
5
SCR must be selected for a holding current of less than
0.5mA at TA(min). The simple two transistor circuit can be
used in
1mA
2R
lace of the SCR as shown. All resistors are 10K.
Error Amp compensation circuit for
R
stabilizing any current-mode topology
except for boost and flyback converters
5
operating with continuous inductor
current
+
1mA
2R
Error Amp compensation circuit for
R
stabilizing current-mode boost and
flyback topologies operating with
5
continuous inductor current.
External Clock Synchronization
8
Vref
R
RT
R
4
CT
External
Sync Input
0.01uF
47Ω
H3842P HSMC Product Specification
2
1
+
-
+
EA
BIAS
OSC
2R
The diode clamp is
required if the Sync
R
5
amplitude is large enough
to cause the bottom side
of CT to go more than
300mV below ground
Page 9
HI-SINCERITY
MICROELECTRONICS CORP.
External Duty Cycle Clamp and Multi Unit Synchronization
Vref
RA
RB 5KΩ
6
5
8
+
-
5KΩ
+
2
C
-
5KΩ
1
f=1.44/((RA+2RB)C), Dmax=RB/(RA+2RB)
4
R
Q
S
NE555
Spec. No. : HP200202
Issued Date : 1998.08.01
Revised Date : 2002.12.03
Page No. : 9/10
8
R
BIAS
R
3
7
4
OSC
+
+
2
EA
1
To Additional
H3842
2R
R
5
Soft-Start Circuit
8
R
R
4
+
2
1MΩ
C
1
+
-
1mA
EA
Soft-Start and Error Amplifier Output Duty Cycle Clamp
8
R
R
4
2
R2
C
R1
1
BC109
+
+
-
1mA
EA
BIAS
OSC
Vclamp
2R
5
5Vref
+
BIAS
OSC
2R
R
5
5Vref
+
-
R
+
1V
-
1V
+
S
Q
R
Comp/Latch
S
+
-
7
Q
R
Vcc Vin
7
6
Q1
5
Rs
Vclamp=R1/(R1+R2) where 0<Vclamp<1V, Ipk(max)=Vclamp/RS
H3842P HSMC Product Specification
Page 10
HI-SINCERITY
g
MICROELECTRONICS CORP.
DIP-8P Dimension
87
1
65
32
Spec. No. : HP200202
Issued Date : 1998.08.01
Revised Date : 2002.12.03
Page No. : 10/10
Marking:
A
3842
PH
Date Code
4
B
J
DIP-8P Plastic Package
HSMC Packa
e Code: P
F
α1
C
DIM
A 0.2480 0.2520 6.29 6.40 H 0.0150 0.0210 0.38 0.53
B 0.3630 0.3670 9.22 9.32 I 0.0898 0.1098 2.28 2.79
C - *0.0600 - *1.52 J 0.2950 0.3050 7.49 7.74
D - *0.0500 - *1.27 K - *0.1181 - *3.00
E - *0.0390 - *0.99 L 0.3370 0.7470 8.56 8.81
F 0.1280 0.1320 3.25 3.35 M 0.0090 0.0150 0.229 0.381
G 0.1250 0.1400 3.17 3.55
Notes: 1.Dimension and tolerance based on our Spec. dated Sep. 07,1997.
2.Controlling dimension: millimeters.
3.Maximum lead thickness includes lead finish thickness, and minimum lead thickness is the minimum thickness of base material.
4.If there is any question with packing specification or packing method, please contact your local HSMC sales office.
Material:
• Lead: 42 Alloy; solder plating
• Mold Compound: Epoxy resin family, flammability solid burning class: UL94V-0
Inches Millimeters Inches Millimeters
Min. Max. Min. Max.
E
G
D
H
I
M
K
L
DIM
α194° 97° 94° 97°
Min. Max. Min. Max.
*: Typical
Important Notice:
• All rights are reserved. Reproduction in whole or in part is prohibited without the prior written approval of HSMC.
• HSMC reserves the right to make changes to its products without notice.
• HSMC semiconductor products are not warranted to be suitable for use in Life-Support Applications, or systems.
HSMC assumes no liability for any consequence of customer product design, infringement of patents, or application assistance.
•
Head Office And Factory:
• Head Office (Hi-Sincerity Microelectronics Corp.): 10F.,No. 61, Sec. 2, Chung-Shan N. Rd. Taipei Taiwan R.O.C.
Tel: 886-2-25212056 Fax: 886-2-25632712, 25368454
• Factory 1: No. 38, Kuang Fu S. Rd., Fu-Kou Hsin-Chu Industrial Park Hsin-Chu Taiwan. R.O.C
Tel: 886-3-5983621~5 Fax: 886-3-5982931
H3842P HSMC Product Specification
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