Advanced
Monolithic
Systems
FEATURES
•
Wide Input Voltage Operating Range from 2.5V to 40V
•
Low Standby Current
•
Current Limiting
•
Output Switch Current of 1.5A
•
Output Voltage Adjustable from 1.25 to 40V
•
Frequency of Operation to 100kHz
AMS34063
DC-TO-DC CONVERTER CONTROL CIRCUIT
APPLICATIONS
•
Step-Up Converter
•
Step-Down Converter
•
Voltage Inverting Application
GENERAL DESCRIPTION
The AMS34063 series is a control circuit containing the basic functions required for DC-to-DC converters. The device consists
of an internal temperature compensated reference, a comparator, a controlled duty cycle oscillator with an active current limit
circuit, a driver and a high current output switch. Designed specifically to be incorporated in Step-Up, Step-Down and Voltage
-Inverting applications, the AMS34063 requires a minimum number of external components.
The AMS34063 is available in the 8-lead plastic SOIC and 8-lead plastic DIP packages.
ORDERING INFORMATION
PACKAGE TYPE
8 LEAD PDIP
AMS34063P
8 LEAD SOIC
AMS34063S
OPER. TEMP
RANGE
-40°C to +85°C
PIN CONNECTIONS
8 LEAD SOIC/ 8 LEAD PDIP
SWITCH
COLLECTOR
SWITCH
EMITTER
TIMING
CAPACITOR
GND
1
2
3
4
DRIVER
COLLECTOR
7 I
PK
SENSE
8
6 V
CC
5 COMPARATOR
INVERTING
INPUT
Top View
Advanced Monolithic Systems, Inc.
6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
AMS34063
ABSOLUTE MAXIMUM RATINGS
(Note 1)
Power Supply Voltage, V
CC
40V
Comparator Input Voltage Range, V
IR
-0.3V to +40V
Switch Collector Voltage, V
C(switch)
40V
Switch Emitter Voltage, V
E(switch)
40V
Switch Collector to Emitter Voltage, V
CE(switch)
40V
Driver Collector Voltage, V
C(driver)
Switch Current, I
SW
Power Dissipation
Maximum Junction Temperature
Storage Temperature
40V
1.5A
(Note 3)
+125°C
-65°C to +150°C
ELECTRICAL CHARACTERISTICS
PARAMETER
Oscillator
Charging Current
Discharge Current
Voltage Swing
Discharge to Charge Current
Ratio
Current Limit Sense Voltage
Output Switch
(Note 2)
Saturation Voltage, Darlington
Connection
Saturation Voltage
DC Current Gain
Collector Off-State Current
Comparator
Threshold Voltage
Threshold Voltage Line
Regulation
Input Bias Current
Total Device
3.0V
≤
V
CC
≤
40V
V
IN
= 0V
Electrical Characteristics at V
CC
= 5.0V, -40°C
≤T
A
≤+85°C,
unless otherwise noted.
CONDITIONS
Min.
5.0V
≤
V
CC
≤
40V, T
A
= 25°C
5.0V
≤
V
CC
≤
40V, T
A
= 25°C
T
A
= 25°C
I
PK(sense)
= V
CC
, T
A
= 25°C
I
CHG
= I
DISCHG
, T
A
= 25°C
250
20
150
AMS34063
Typ.
35
200
0.5
6.0
300
Units
Max.
50
250
µA
µA
V
P-P
_
350
mV
I
SW
= 1.0A, V
C(driver)
= V
C(switch)
I
SW
= 1.0A, I
C(driver)
= 50mA, (Forced
β ≈
20)
I
SW
= 1.0A, V
CE
= 5.0V, T
A
= 25°C
V
CE
= 40V, T
A
= 25°C
1.0
0.45
35
10
1.3
0.7
120
V
V
nA
1.18
1.25
0.04
40
1.32
0.2
400
V
mV/V
nA
5.0V
≤
V
CC
≤
40V, I
PK(sense)
= V
CC
,
2.4
3.5
mA
C
T
= 0.001µF, V pin 5 > V
th
,
Pin 2 = Gnd, Remaining pins open
Note 1:
Absolute Maximum Ratings are limits beyond which damage to the device may occur. For guaranteed performance limits and associated test
conditions, see the Electrical Characteristics tables.
Note 2:
To minimize power dissipation, low duty cycle pulse testing is used.
Note 3:
Power dissipation at T
A
= 25°C is equal to 1.0W for the 8 lead P DIP package and 625mW for the SO-8 package. For operation at temperatures above
T
A
= 25°C derate the power dissipation at 10mW/°C.
Supply Current
Advanced Monolithic Systems, Inc.
6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
AMS34063
FUNCTIONAL BLOCK DIAGRAM
DRIVE
COLLECTOR
8
S
R
170
I
PK
SENSE
7
I
PK
OSC
V
CC
6
+
COMP.
-
COMPARATOR
INVERTING
INPUT
5
1.25V
REF
REG
4
GND
2
SWITCH
EMITTER
Q
Q
2
Q
1
1
SWITCH
COLLECTOR
C
T
3
TIMING
CAPACITOR
TYPICAL PERFORMANCE CHARACTERISTICS
Output Switch On-Off Time vs
Oscillator Timing Capacitor
OUTPUT SWITCH ON-OFF TIME (µs)
1000
SUPPLY CURRENT (mA)
V
CC
= 5.0V
I
PK(sense)
= V
CC
Pin 5 = GND
Standby Supply Current vs
Supply Voltage
3.2
C
T
= 0.001µF
I
PK(sense)
= V
CC
Pin 2 = GND
2.4
100
1.6
10
0.8
1.0
100
0.1
1.0
10
OSCILLATOR TIMING CAPACITOR
0
0
5.0 10 15 20 25 30 35 40
SUPPLY VOLTAGE (V)
Emitter-Follower Configuration
Output Switch Saturation Voltage
vs Emitter Current
1.6
SATURATION VOLTAGE (V)
1.5
1.4
1.3
1.2
1.1
1.0
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4
EMITTER CURRENT (A)
SATURATION VOLTAGE (V)
V
CC
= 5.0V
Pins 1,7,8 = V
CC
Pin 3,5 = GND
Common-Emitter Configuration
Output Switch Saturation Voltage
vs Collector Current
1.2
1.0
0.8
0.6
0.4
0.2
0
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4
COLLECTOR CURRENT (A)
V
CC
= 5.0V
Pin 7 = V
CC
Pin 2,3,5 = GND
Darlington Connection
Forced Beta
≈20
Advanced Monolithic Systems, Inc.
6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
AMS34063
TYPICAL APPLICATIONS
Step-Down Converter
8
S
R
Q
Q
2
Q
1
1
7
I
PK
OSC
6
100
µF
+
+
COMP.
-
5
1.25V
REF
REG
2
R
SC
0.33
V
IN
25V
C
T
1N5822
3
C
T
470
pF
4
L
220µH
R
2
R
1
1.2 k
3.6 k
470
µF
+
C
O
V
OUT
5.0V/500mA
Test
Line Regulation
Load Regulation
Output Ripple
Short Circuit Current
Efficiency
Conditions
V
IN
= 15 to 25V, I
O
= 500mA
V
IN
= 25V, I
O
= 50 to 500mA
V
IN
= 25V, I
O
= 500mA
V
IN
= 25V, R
L
= 0.1Ω
V
IN
= 25V, I
O
= 500mA
15mV
5.0mV
Results
40 mV
P-P
2.3A
84.7%
External Current Boost Connections for I
C
Peak Greater than 1.5A
a. External NPN Switch
b. External PNP Saturated Switch
8
1
8
1
V
OUT
7
R
SC
V
IN
6
2
V
OUT
R
SC
V
IN
7
2
6
Advanced Monolithic Systems, Inc.
6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
AMS34063
TYPICAL APPLICATIONS
(Continued)
Step-Up Converter
170µH
L
8
180
S
R
Q
Q
2
Q
1
1
7
I
PK
OSC
6
100
µF
+
+
COMP.
-
5
1.25V
REF
REG
2
R
SC
0.22
V
IN
12V
C
T
3
C
T
1500
pF
4
1N5819
R
2
R
1
2.2 k
47 k
150
µF
+
C
O
V
OUT
28V/175mA
Test
Line Regulation
Load Regulation
Output Ripple
Short Circuit Current
Efficiency
Conditions
V
IN
= 8 to 16V, I
O
= 175 mA
V
IN
= 12V, I
O
= 75 to 175 mA
V
IN
= 12V, I
O
= 175 mA
V
IN
= 12V, R
L
= 0.1Ω
V
IN
= 12V, I
O
= 175 mA
12 mV
5.0 mV
Results
40 mV
P-P
2.3A
84.7%
External Current Boost Connections for I
C
Peak Greater than 1.5A
a. External NPN Switch
b. External NPN Saturated Switch
18
0
8
1
V
OUT
8
180
1
V
OUT
7
R
SC
V
IN
6
2
R
SC
V
IN
7
2
6
R 0 for
constant V
IN
Advanced Monolithic Systems, Inc.
6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
京公网安备 11010802033920号
EEWORLD
