AMC DOC. #: AMC34063_C
November 2002
Copyright 2002, ADD Microtech Corp. 1 www.addmtek.com
DESCRIPTION FEATURES
The AMC34063A is designed for the applications which require
DC - DC converters. It can be operated in a wide input range
from 3.0V to 40V and has the controlled duty cycle oscillator,
driver and high current output switch. Also, With the internal
temperature compensation circuit, the AMC34063A provides an
internally trimmed precision 2% reference voltage of 1.25V.
These features make the AMC34063A suitable for step-up,
step-down and voltage–inverting applications.
! Wide Input Operating Range:
3.0V to 40V
! Output Switch Current up to
1.5A
! 100KHz operational Frequency
! Low Standby Current
# Internally trimmed 2% 1.25V
Reference Voltage
# Adjustable Output Voltage
# Available in 8 Pin Plastic DIP
and 8 Pin S.O Packages
# Direct pin-to-pin replacement for
industrial product MC34063A.
APPLICATIONS PACKAGE PIN OUT
# Chargers
# Adaptors
# Mother Board
# Scanner
ORDER INFORMATION
Plastic DIP Plastic SO-8
TA (°C) M 8-pin DM 8-pin
0 to 70 AMC34063AM AMC34063ADM
Note: All surface-mount packages are available in Tape & Reel. Append the letter “T” to part number (i.e.
AMC34063ADMT).
DC - DC CONVERTER
CONTROL CIRCUITS
AMC34063A
1
2
3
4
8
7
6
5
M PACKAGE
(TOP VIEW)
1
2
3
4
8
7
6
5
DM PACKAGE
(TOP VIEW)
SC DrC
ISEN
SE
Cap VCC
V
FB
GND
SC DrC
ISEN
SE
Cap VCC
V
FB
GND
A
AA
ADD MICROTECH CORP.
AMC DOC. #: AMC34063_C AMC34063A
November 2002 DC - DC CONVERTER CONTROL CIRCUITS
Copyright 2002, ADD Microtech Corp. 2 www.addmtek.com
ABSOLUTE MAXIMUM RATINGS
Power Supply Voltage (VCC) ………………………………………………………………………………..…40V
Operating Junction temperature (M, DM Packages) ………………………………................................ 150 °C
Storage Temperature Range …………………………………………………………………...…. -65°C to 150°C
Lead temperature (Soldering, 10 seconds) …………………………………………………………..………300°C
Note 1: Exceeding these ratings could cause damage to the device. All voltages are with respect to Ground.
Currents are positive into, negative out of the specified terminal.
THERMAL DATA
M PACKAGE:
Power dissipation (PD), TA = 25 °C 1.31W
Thermal Resistance-Junction to Ambient, θJA 95°C /W
DM PACKAGE:
Power dissipation (PD), TA = 25 °C 757mW
Thermal Resistance-Junction to Ambient, θJA 165°C /W
BLOCK DIAGRAM
Oscillator
4
3
Gnd
Cap
1.25V
Reference
C
T
2
1
SE
SC
100
Q2
Q1 Q
Isen
5
6
V
FB
V
CC
7
8
R
S
SEN
I
DrC
Pin Assignment Descriptions
Pin 1 : SC - Switch Collector Pin 8 : DrC - Driver Collector
Pin 2 : SE - Switch Emitter Pin 7 : ISEN - I Peak Sense
Pin 3 : Cap - Oscillator Timing Capacitor Pin 6 : VCC - Power Supply
Pin 4 : GND - Ground Pin 5 : VFB - Comparator inverting input
AMC DOC. #: AMC34063_C AMC34063A
November 2002 DC - DC CONVERTER CONTROL CIRCUITS
Copyright 2002, ADD Microtech Corp. 3 www.addmtek.com
RECOMMENDED OPERATING CONDITIONS
Recommended Operating
Parameter Symbol Min. Typ. Max. Units
Comparator Input Voltage VFB -0.3 to + 40 V
Switch Collector Voltage VC(switch) 40 V
Switch Emitter Voltage (VPin1=40V) VE(switch) 40 V
Switch Collector to Emitter Voltage VCE(switch) 40 V
Driver Collector Voltage VC(driver) 40 V
Driver Collector Current (Note 1) IC(driver) 100 mA
Switch Current ISW 1.5 A
Timing Capacitor (connected to Cap pin) CT 1 nF
Operating Ambient Temperature Range TA 0 to +70 °C
Note 1: Maximum package power dissipation limits must be observed.
ELECTRICAL CHARACTERISTICS
VCC=5.0 V, TA=0°C to 70°C, unless otherwise specified.
AMC34063A
Parameter Symbol Test Conditions Min. Typ. Max. Units
OSCILLATOR
Frequency fosc VPin 5 = 0 V, CT = 1.0 nF, TA = 25°C 24 33 42 KHz
Charge Current Ichg VCC = 5.0 V to 40 V, TA = 25°C 24 35 42 µA
Discharge Current Idischg VCC = 5.0 V to 40 V, TA = 25°C 140 220 260 µA
Discharge to Charge Current Ratio Idischg/Ichg Pin 7 to VCC, TA = 25°C 5.2 6.5 7.5 -
Current Limit Sense Voltage Vsense Ichg = Idischg, TA = 25°C 250 300 350 mV
OUTPUT SWITCH
Saturation Voltage, Darlington Connection VCE(sat) I
SW = 1.0 A, Pins 1, 8 connected - 1.0 1.3 V
Saturation Voltage VCE(sat) ISW = 1.0 A, Rpin 8 =82 to VCC,
Forced β = 20 - 0.45 0.7 V
DC Current Gain hFE ISW = 1.0 A, VCE = 5.0 V, TA = 25°C 50 75 - -
Collector OffState Current IC(off) V
CE = 40 V - 0.01 100 µA
COMPARATOR
TA = 25°C 1.225 1.25 1.275
Threshold Voltage Vth TA =0°C to 70°C 1.21 - 1.29 V
Threshold Voltage Line Regulation Regline V
CC = 3.0 V to 40 V - 1.4 5.0 mV
Input Bias Current IIB V
FB = 0 V - -20 -400 nA
TOTAL DEVICE
Supply current ICC
VCC = 5.0 V to 40 V,
CT = 1.0nF, Pin 7 = VCC,
VFB > Vth, Pin 2= GND, remaining
pins open
- - 4.0 mA
AMC DOC. #: AMC34063_C AMC34063A
November 2002 DC - DC CONVERTER CONTROL CIRCUITS
Copyright 2002, ADD Microtech Corp. 4 www.addmtek.com
CHARACTERIZATION CURVES
SE pin (PIN#2) waveform
on 5V step down converter
VCC = 25V, 500mA load
CT = 470pF
Cap pin (PIN#3 ) waveform
Cap pin (PIN#3 ) waveform
Cap pin (PIN#3 ) waveform
VCC = 5V, Pin 1, 5, 8 open
CT = 1nF
VCC = 5V, Pin 1, 5, 8 open
CT = 1nF
VCC = 5V, Pin 1, 5, 8 open
CT = 1nF
23.3V
- 0.8V
AMC DOC. #: AMC34063_C AMC34063A
November 2002 DC - DC CONVERTER CONTROL CIRCUITS
Copyright 2002, ADD Microtech Corp. 5 www.addmtek.com
Figure 1 – Step-Up Converter Application Circuits
170uH
L
1.25V
Reference
Oscillator
28V/175mA
V
OUT
330uF
4
1500pF
3
C
T
2
Q1
1
Q2 Q
Isen
2.2K
5
47K
6
100uF
12V
V
IN
180
R
7
S
8
0.22
Rsc
Figure 2 – Step-Down Converter Application Circuit
Oscillator
1.25V
Reference
C
T
V
OUT
5V/500mA
470uF
4
470pF
3
220uH
L
1N5819
2
Q1
1
Q2 Q
V
IN
5
3.6K
6
1.2K
100uF
25V
Isen
R
7
S
8
Rsc
0.33
R1
R2
R1
R2
Co
Co
AMC DOC. #: AMC34063_C AMC34063A
November 2002 DC - DC CONVERTER CONTROL CIRCUITS
Copyright 2002, ADD Microtech Corp. 6 www.addmtek.com
Figure 3 – Voltage Inverting Converters
Note: For step-up, step-down or voltage inverting applications requiring peak current greater than
1.5A, external boost current circuitry by NPN or PNP transistors can be used.
1.25V
Reference
C
T
1500pF
-12V/100mA
V
OUT
1000uF
4
3
L
1N5819
88uH
2
1
Q2
Q1
V
IN
3.6K
5
6
1.2K
4.5V to 6.0V
100uF
Ipk
Oscillator
R
7
QS
8
0.24
Rsc
8.2K
953
R1
R2
Co
AMC DOC. #: AMC34063_C AMC34063A
November 2002 DC - DC CONVERTER CONTROL CIRCUITS
Copyright 2002, ADD Microtech Corp. 7 www.addmtek.com
Typical Design Reference Table:
Calculation Step-Down Step-Up Voltage-Inverting
ton/toff Vout + VF
Vin(min) Vsat Vout Vout + VF Vin(min)
Vin(min) Vsat !Vout! + VF
Vin Vsat
ton + toff 1
f 1
f 1
f
toff ton + toff
ton/tof f + 1 ton + toff
ton/tof f + 1 ton + toff
ton/tof f + 1
ton (ton + toff) toff (ton + toff) toff (ton + toff) toff
CT 4.0 × 10-5 ton 4.0 × 10-5 ton 4.0 × 10-5 ton
Ipk(switch) 2Iout(max) 2Iout(max) (ton/toff + 1) 2Iout(max) (ton/toff + 1)
RSC 0.3/Ipk(switch) 0.3/Ipk(switch) 0.3/Ipk(switch)
L(min) ((Vin(min) Vsat Vout)
Ipk(switch)
)
ton(max)
(
(Vin(min) Vsat)
Ipk(switch)
)
ton(max)
(
(Vin(min) Vsat)
Ipk(switch)
)
ton(max)
CO Ipk(switch)( ton + toff)
8Vripple(pp) 9 Iout ton
Vripple(pp)
9 Iout ton
Vripple(pp)
VF: Forward Voltage drop of the output rectifier
Vsat: Saturation voltage of the output switch.
The following power supply characteristics must be chosen:
Vin - Nominal input voltage
V
out - Desired output voltage, !Vout! = 1.25(1 + R1/R2)
I
out - Desired output current.
f
min – Minimum desired output switching frequency at the selected values of Vin and IO
V
ripple(pp) Desired peak – to – peak output ripple voltage.
Application concerns:
To get the best regulation performance, Low ESR capacitors at Vout are suggested.
AMC DOC. #: AMC34063_C AMC34063A
November 2002 DC - DC CONVERTER CONTROL CIRCUITS
Copyright 2002, ADD Microtech Corp. 8 www.addmtek.com
8-Pin Plastic DIP
INCHES MILLIMETERS
MIN TYP MAX MIN TYP MAX
A 0.355 0.365 0.400 9.02 9.27 10.16
B 0.240 0.250 0.280 6.10 6.35 7.11
C - - 0.210 - - 5.33
D - 0.018 - - 0.46 -
F - 0.060 - - 1.52 -
G - 0.100 - - 2.54 -
H 0.050 - 0.090 1.27 - 2.29
J 0.008 - 0.015 0.20 - 0.38
K 0.115 0.130 0.150 2.92 3.30 3.81
L 0.300 BSC. 7.62 BSC.
M - 15º - 15º
Note: For 8 -pin Pl astic package, 60 units pe r tube
8-Pin Plastic S.O.I.C.
INCHES MILLIMETERS
MIN TYP MAX MIN TYP MAX
A 0.183 - 0.202 4.65 - 5.13
B 0.144 - 0.163 3.66 - 4.14
C 0.068 - 0.074 1.73 - 1.88
D 0.010 - 0.020 0.25 - 0.51
F 0.015 - 0.035 0.38 - 0.89
G 0.050 BSC 1.27 BSC
J 0.007 - 0.010 0.19 - 0.25
K 0.005 - 0.010 0.13 - 0.25
L 0.189 - 0.205 4.80 - 5.21
M - - 8º - -
P 0.228 - 0.244 5.79 - 6.20
1
B
5
4
8
C
K
F
H G D
A
L
M
J
SEATING PLAN
A
D
F
P
B
K
C
M
L
J
G
SEATING PLANE
AMC DOC. #: AMC34063_C AMC34063A
November 2002 DC - DC CONVERTER CONTROL CIRCUITS
Copyright 2002, ADD Microtech Corp. 9 www.addmtek.com
IMPORTANT NOTICE
ADD Microtech (ADDM) reserves the right to make changes to its products or to discontinue any integrated circuit
product or service without notice, and advises its customers to obtain the latest version of relevant information to
verify, before placing orders, that the information being relied on is current.
A few applications using integrated circuit products may involve potential risks of death, personal injury, or severe
property or environmental damage. ADDM integrated circuit products are not designed, intended, authorized, or
warranted to be suitable for use in life-support applications, devices or systems or other critical applications. Use of
ADDM products in such applications is understood to be fully at the risk of the customer. In order to minimize
risks associated with the customers applications, the customer should provide adequate design and operating
safeguards.
ADDM assumes to no liability to customer product design or application support. ADDM warrants the performance
of its products to the specifications applicable at the time of sale.
U.S. Asia Pacific
ADD Microtech Inc.
492 Altamont Drive
Milpitas, CA 95035
ADD Microtech Corp
3F, 132, Sec. 4, Chung Hsiao E. Rd.,
Taipei, Taiwan
TEL: (408) 9410420 TEL: 2-27760166
FAX: (408) 9410864 FAX: 2-27764208