ETC BM34063

BM34063
DC-DC CONVERTER
Features
Description
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The BM34063 Series is a monolithic control circuit
containing the primary functions required for DC-to-DC
converters. These devices consist of an internal
temperature compensated reference, comparator,
controlled duty cycle oscillator with an active current limit
circuit, driver and high current output switch.
3V to 40V Input Voltage Operation
Internal 1.6A Peak Current Switch
Internal ±1.8% Reference
Low Quiescent Current at 1.6mA
Frequency Operation from 100Hz~100KHz
Output Voltage Adjustable
Active Current Limiting
Step-Up, Step-Down or Inverting Switching
Regulators
Pin Assignment
DIP/SOP-8
1
SWC
DRC
8
2
SWE
Ipk
7
3
TC
VCC
6
4
GND
FB
5
Pin1: Switch Collector (SWC)
Pin5: Comparator Inverting Input (FB)
Pin2: Switch Emitter (SWE)
Pin6: Voltage Supply (Vcc)
Pin3: Timing Capacitor (TC)
Pin7: Ipk Sense (Ipk)
Pin4: Ground (GND)
Pin8: Voltage Driver Collector (DRC)
Ordering Information
Part Number
BM34063HP
BM34063HS
2004/06/15
Package
DIP-8
SOP-8
1
BM34063
DC-DC CONVERTER
Absolute Maximum Ratings
(Ta=25°C, Unles Otherwise Specified)
Parameter
Symbol
Value
Unit
Power Supply Voltage
VCC
40
V
Comparator Input Voltage Range
Vir
-0.3~+40
V
Switch Collector Voltage
VC(SW)
40
V
Switch Emitter Voltage
VSWE
40
V
Switch Emitter to Collector Voltage
VCE
40
V
VC(DR)
40
V
Switch Current
ISW
1.5
A
Power Dissipation at Ta=25oC
PD
Operating Ambient Temperature Range
Topr
Driver Collector Voltage
Storage Temperature Range
DIP-8
1
SO-8
0.625
Tstg
Operating Junction Temperature
Topj
Thermal Resistance Junction-ambient
θJA
W
0~+70
o
-65~+150
o
120
o
C
C
C
o
125
C/W
Block Diagram
DRI
SC
Pin8: Driver Collector
Pin1: 1.6A Switch Collector
Q
Q2
Q1
S
R
80Ω
IPK
SE
Pin2: Darlington Switch Emitter
IPK
CT
Pin7: Highside Current Sense
Input, VCC-VIPK=300mV
Oscillator
VCC
TC
Comparator
Pin3: Oscilletor Timing Capacitor
1.25V
Reference Voltage
GND
Pin4: Power GND
2004/06/15
Pin6: Power Supply Input
+
FB
Pin5: Feedback Comparator
Inverting Input
2
BM34063
DC-DC CONVERTER
Electrical Characteristics (VCC=5V,Ta=0~70°C, unless otherwise specified)
Parameter
Symbol
Test Condition
Min.
Typ.
Max.
Unit
10
25
40
uA
140
190
240
uA
28
33
40
KHz
5.2
6
7.5
250
300
350
mV
Oscillator
Charging Current
Ichg
Discharge Current
Idischg
Frequency
fOSC
Discharge to Charge Current Ratio
Idischg/Ichg
Current Limit Sense Voltage
VIPK
VCC=5~40V, Ta=25oC
o
VCC=5~40V, Ta=25 C
o
VPIN5=0, CT=1nF, Ta=25 C
o
VPIN7=VCC, Ta=25 C
o
Idischg=Ichg, Ta=25 C
Output Switch
Saturation Voltage,
Darlington Connection
Saturation Voltage
VCE(sat) 1
ISW=1A, VC(SW)=VC(DR)
-
1
1.3
V
VCE(sat) 2
ISW=1A, IC(DR)=50mA
-
0.4
0.7
V
35
120
-
-
10
100
uA
1.23
1.25
1.27
V
VCC=5~40V
-
1.5
6
mV
IIB
VIN=0V
-
40
400
nA
ICC
VCC=5~40V, VPIN7=VCC, VPin5>VFB,
CT=0.001uF, Pin7=GND,
Remaining pins open
-
1.6
3
mA
DC Current Gain
hFE
Collector Off-State Current
ICC(off)
ISW=1A, VCE=5V
o
VCE=40V, Ta=25 C
Comparator
Threshold Voltage
VFB
Threshold Voltage Line Regulation
Input Bias Current
∆VFB
Total Device
Supply Current
Application Information
Design Formula 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(max)-Vsat)
(ton+toff) max
1/Fmin
1/Fmin
1/Fmin
-5
-5
CT
4*10 ton
4*10 ton
4*10-5ton
IC(sw)
2*Iout(max)
2*Iout(max)(ton+toff/toff)
2*Iout(max)(ton+toff/toff)
RS
0.3/IC(sw)
0.3/IC(sw)
0.3/IC(sw)
L(min)
(Vin(min)-Vsat/Ipk(sw))*ton(max)
(Vin(min)-Vsat/Ipk(sw))*ton(max)
(Vin(min)-Vsat/Ipk(sw))*ton(max)
CO
(Ipk(sw)*(ton+toff))/(8*Vripple(P-P))
Iout*ton/Vripple(P-P)
Iout*ton/Vripple(P-P)
Vsat: Saturation voltage of the output switch.
VF: Forward voltage drop of the ringback rectifier.
The following power supply characteristics must be chosen:
Vin: Nominal input voltage.
Vout: Desired output voltage. |Vout|=1.25*(1+RB/RA)
Iout: Desired output current
Fmin: Minimum desired output switching frequency at the selected values for Vin and Iout.
Vripple(P-P): Desired peak to peak output ripple voltage in practice, the calculated value will need to be increased due to
the capacitor equivalent series resistance and board layout. The ripple voltage should be kept to a low value since it
will directly effect the line and load regulation.
2004/06/15
3
BM34063
DC-DC CONVERTER
Application Information (Continued)
D1
L1
200uH
R1
1N5819
BM34063
150Ω
RSC
0.22
Vin
C1
8
1
7
2
6
3
5
4
Vout
28V / 200mA
Cout
220uF
CT
680pF
100uF
RB
RA
Line Regulation: 100mV (Vin=8V~16V, @Io=200mA)
Load Regulation: 5mV (Vin=12V, @Io=80mA~200mA)
47kΩ
2.2kΩ
Fig.2 Step-Up Converter
L1
BM34063
R1
RSC
Vin
8
1
7
2
6
3
5
4
Vout
D1
Q1
C1
CT
Cout
R2
RB
RA
Fig.3 Step-Up Converter With External NPN Switch
L1
BM34063
RSC
0.25
8
1
7
2
6
3
5
Vin
200uH
Vout
5V / 500mA
Cout
D1
4
470uF
1N5819
CT
470pF
RB
C1
100uF
RA
1.2kΩ
3.6kΩ
Line Regulation: 40mV (Vin=10V~20V, @Io=500mA)
Load Regulation: 5mV (Vin=15V, @Io=10mA~500mA)
Short Circuit Current: 1.3A (Vin=15V, @RL=0.1Ω
Fig.4 Step-Down Converter
2004/06/15
4
BM34063
DC-DC CONVERTER
BM34063
R2
RSC
Vin
8
1
7
2
6
3
5
4
R1
Q1
L1
Vout
CT
D1
Cout
RB
C1
RA
Fig.5 Step-Down Converter With External PNP Saturation Switch
D1
Vout
-12V / 100mA
BM34063
RSC
0.25
Vin
4.5V-6V
8
1
7
2
6
3
4
5
1N5819
L1
Cout
100uH
470uF
CT
680pF
RA
C1
100uF
RB
953Ω
8.2kΩ
Line Regulation: 20mV (Vin=4.5V~6V, @Io=100mA)
Load Regulation: 100mV (Vin=5V, @Io=10mA~100mA)
Fig.6 Voltage Inverting Converter
BM34063
RSC
Vin
8
1
7
2
6
3
5
4
R2
R1
Q1
L1
D1
CT
RA
Vout
C1
RB
Cout
Fig.7 Voltage Inverting Converter With External PNP Saturation Switch
2004/06/15
5
BM34063
DC-DC CONVERTER
DIP-8 (P) Dimension
6
7
8
DIM
A
B
C
D
E
F
G
H
I
J
K
L
M
α1
5
A
1
2
4
3
B
J
F
E
C
α1 K
G
Min.
6.29
9.22
3.25
3.17
0.38
2.28
7.49
8.56
0.229
o
94
Max.
6.40
9.32
*1.52
*1.27
*0.99
3.35
3.55
0.53
2.79
7.74
*3.00
8.81
0.381
o
97
*: Typical, Unit: mm
D
I
M
H
L
8-Lead DIP-8
Plastic Package
SOP-8 (S) Dimension
A
7
8
B
G
6
C
Pin1 Index
2
3
I
5
H
4
J
D
K
E
Part A
Part A
M
L
N
O
DIM
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
Min.
4.85
3.85
5.80
1.22
0.37
3.74
1.45
4.80
0.05
0.30
0.19
0.37
0.23
0.08
0.00
Max.
5.10
3.95
6.20
1.32
0.47
3.88
1.65
5.10
0.20
0.70
0.25
0.52
0.28
0.13
0.15
*: Typical, Unit: mm
F
8-Lead SO-8 Plastic
Surface Mounted Package
2004/06/15
6
BM34063
DC-DC CONVERTER
Soldering Methods
1. Storage environment: Temperature=10oC~35oC Humidity=65%±15%
2. Reflow soldering of surface-mount devices
Figure 1: Temperature profile
tP
Critical Zone
TL to TP
TP
Ramp-up
TL
tL
Temperature
Tsmax
Tsmin
tS
Preheat
Ramp-down
25
t 25oC to Peak
Time
Profile Feature
Sn-Pb Eutectic Assembly
Pb-Free Assembly
<3 C/sec
<3oC/sec
100oC
150oC
60~120 sec
150oC
200oC
60~180 sec
<3oC/sec
<3oC/sec
Time maintained above:
- Temperature (TL)
- Time (tL)
183oC
60~150 sec
217oC
60~150 sec
Peak Temperature (TP)
240oC +0/-5oC
260oC +0/-5oC
Time within 5 C of actual Peak
Temperature (tP)
10~30 sec
20~40 sec
Ramp-down Rate
<6oC/sec
<6oC/sec
<6 minutes
<8 minutes
Peak temperature
Dipping time
245 C ±5 C
5sec ±1sec
Average ramp-up rate (TL to TP)
Preheat
- Temperature Min (Tsmin)
- Temperature Max (Tsmax)
- Time (min to max) (ts)
Tsmax to TL
- Ramp-up Rate
o
o
Time 25oC to Peak Temperature
3. Flow (wave) soldering (solder dipping)
Products
Pb devices.
Pb-Free devices.
2004/06/15
o
o
o
o
260 C +0/-5 C
5sec ±1sec
7