Semiconductor Components Industries, LLC, 2001
October, 2001 – Rev. 2 1Publication Order Number:
BC856AWT1/D
BC856AWT1 Series,
BC857BWT1 Series,
BC858AWT1 Series
Preferred Devices
General Purpose
Transistors
PNP Silicon
These transistors are designed for general purpose amplifier
applications. They are housed in the SOT–323/SC–70 which is
designed for low power surface mount applications.
Device Marking:
BC856AWT1 = 3A
BC856BWT1 = 3B
BC857BWT1 = 3F
BC857CWT1 = 3G
BC858AWT1 = 3J
BC858BWT1 = 3K
MAXIMUM RATINGS
Rating Symbol BC856 BC857 BC858 Unit
Collector–Emitter Voltage VCEO –65 –45 –30 V
Collector–Base Voltage VCBO –80 –50 –30 V
Emitter–Base V oltage VEBO –5.0 –5.0 –5.0 V
Collector Current –
Continuous IC–100 –100 –100 mAdc
THERMAL CHARACTERISTICS
Characteristic Symbol Max Unit
Total Device Dissipation
FR–5 Board (1)
TA = 25°C
PD150 mW
Thermal Resistance,
Junction to Ambient RJA 833 °C/W
Junction and Storage
Temperature Range TJ, Tstg –55 to +150 °C
1. FR–5 = 1.0 x 0.75 x 0.062 in
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Device Package Shipping
ORDERING INFORMATION
BC856BWT1 SOT–323
SOT–323/SC–70
CASE 419
STYLE 3
3000 Units/Reel
DEVICE MARKING
Preferred devices are recommended choices for future use
and best overall value.
BC857BWT1 SOT–323 3000 Units/Reel
BC858AWT1 SOT–323 3000 Units/Reel
See Device
Marking Listing
BC856AWT1 SOT–323 3000 Units/Reel
12
3
COLLECTOR
3
1
BASE
2
EMITTER
BC858BWT1 SOT–323 3000 Units/Reel
BC857CWT1 SOT–323 3000 Units/Reel
BC856AWT1 Series, BC857BWT1 Series, BC858AWT1 Series
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ELECTRICAL CHARACTERISTICS (TA = 25°C unless otherwise noted)
Characteristic Symbol Min Typ Max Unit
OFF CHARACTERISTICS
Collector–Emitter Breakdown Voltage BC856 Series
(IC = –10 mA) BC857 Series
BC858 Series
V(BR)CEO –65
–45
–30
V
Collector–Emitter Breakdown Voltage BC856 Series
(IC = –10 µA, VEB = 0) BC857B Only
BC858 Series
V(BR)CES –80
–50
–30
V
Collector–Base Breakdown Voltage BC856 Series
(IC = –10 A) BC857 Series
BC858 Series
V(BR)CBO –80
–50
–30
V
Emitter–Base Breakdown Voltage BC856 Series
(IE = –1.0 A) BC857 Series
BC858 Series
V(BR)EBO –5.0
–5.0
–5.0
V
Collector Cutoff Current (VCB = –30 V)
Collector Cutoff Current (VCB = –30 V, TA = 150°C) ICBO
–15
–4.0 nA
µA
ON CHARACTERISTICS
DC Current Gain BC856A, BC585A
(IC = –10 µA, VCE = –5.0 V) BC856B, BC857B, BC858B
BC857C
(IC = –2.0 mA, VCE = –5.0 V) BC856A, BC858A
BC856B, BC857B, BC858B
BC857C
hFE
125
220
420
90
150
270
180
290
520
250
475
800
Collector–Emitter Saturation Voltage
(IC = –10 mA, IB = –0.5 mA)
(IC = –100 mA, IB = –5.0 mA)
VCE(sat)
–0.3
–0.65
V
Base–Emitter Saturation Voltage
(IC = –10 mA, IB = –0.5 mA)
(IC = –100 mA, IB = –5.0 mA)
VBE(sat)
–0.7
–0.9
V
Base–Emitter On Voltage
(IC = –2.0 mA, VCE = –5.0 V)
(IC = –10 mA, VCE = –5.0 V)
VBE(on) –0.6
–0.75
–0.82
V
SMALL–SIGNAL CHARACTERISTICS
Current–Gain – Bandwidth Product
(IC = –10 mA, VCE = –5.0 Vdc, f = 100 MHz) fT100 MHz
Output Capacitance
(VCB = –10 V, f = 1.0 MHz) Cob 4.5 pF
Noise Figure
(IC = –0.2 mA, VCE = –5.0 Vdc, RS = 2.0 k,
f = 1.0 kHz, BW = 200 Hz)
NF 10 dB
BC856AWT1 Series, BC857BWT1 Series, BC858AWT1 Series
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BC857/BC858
Figure 1. Normalized DC Current Gain
IC, COLLECTOR CURRENT (mAdc)
2.0
Figure 2. “Saturation” and “On” Voltages
IC, COLLECTOR CURRENT (mAdc)
-0.2
0.2
Figure 3. Collector Saturation Region
IB, BASE CURRENT (mA)
Figure 4. Base–Emitter Temperature Coefficient
IC, COLLECTOR CURRENT (mA)
-0.6
-0.7
-0.8
-0.9
-1.0
-0.5
0
-0.2
-0.4
-0.1
-0.3
1.6
1.2
2.0
2.8
2.4
-1.2
-1.6
-2.0
-0.02 -1.0 -10
0-20
-0.1
-0.4
-0.8
hFE, NORMALIZED DC CURRENT GAIN
V, VOLTAGE (VOLTS)
VCE, COLLECTOR-EMITTER VOLTAGE (V)
VB, TEMPERATURE COEFFICIENT (mV/ C)°θ
1.5
1.0
0.7
0.5
0.3
-0.2 -10 -100
-1.0
TA = 25°C
VBE(sat) @ IC/IB = 10
VCE(sat) @ IC/IB = 10
VBE(on) @ VCE = -10 V
VCE = -10 V
TA = 25°C
-55°C to +125°C
IC = -100 mA
IC = -20 mA
-0.5 -1.0 -2.0 -5.0 -10 -20 -50 -100 -200 -0.1 -0.2 -0.5 -1.0 -2.0 -5.0 -10 -20 -50 -100
IC = -200 mAIC = -50 mAIC =
-10 mA
Figure 5. Capacitances
VR, REVERSE VOLTAGE (VOLTS)
10
Figure 6. Current–Gain – Bandwidth Product
IC, COLLECTOR CURRENT (mAdc)
-0.4
1.0
80
100
200
300
400
60
20
40
30
7.0
5.0
3.0
2.0
-0.5
C, CAPACITANCE (pF)
f, CURRENT-GAIN - BANDWIDTH PRODUCT (MHz)
T
TA = 25°C
Cob
Cib
-0.6 -1.0 -2.0 -4.0 -6.0 -10 -20 -30 -40
150
-1.0 -2.0 -3.0 -5.0 -10 -20 -30 -50
VCE = -10 V
TA = 25°C
TA = 25°C
1.0
BC856AWT1 Series, BC857BWT1 Series, BC858AWT1 Series
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BC856
Figure 7. DC Current Gain
IC, COLLECTOR CURRENT (mA)
Figure 8. “On” Voltage
IC, COLLECTOR CURRENT (mA)
-0.8
-1.0
-0.6
-0.2
-0.4
1.0
2.0
-0.1 -1.0 -10 -200
-0.2
0.2
0.5
-0.2 -1.0 -10 -200
TJ = 25°C
VBE(sat) @ IC/IB = 10
VCE(sat) @ IC/IB = 10
VBE @ VCE = -5.0 V
Figure 9. Collector Saturation Region
IB, BASE CURRENT (mA)
Figure 10. Base–Emitter Temperature Coefficient
IC, COLLECTOR CURRENT (mA)
-1.0
-1.2
-1.6
-2.0
-0.02 -1.0 -10
0-20
-0.1
-0.4
-0.8
VCE, COLLECTOR-EMITTER VOLTAGE (VOLTS)
VB, TEMPERATURE COEFFICIENT (mV/ C)°θ
-0.2 -2.0 -10 -200
-1.0
TJ = 25°C
IC =
-10 mA
hFE, DC CURRENT GAIN (NORMALIZED)
V, VOLTAGE (VOLTS)
VCE = -5.0 V
TA = 25°C
0-0.5 -2.0 -5.0 -20 -50 -100
-0.05 -0.2 -0.5 -2.0 -5.0
-100 mA
-20 mA
-1.4
-1.8
-2.2
-2.6
-3.0
-0.5 -5.0 -20 -50 -100
-55°C to 125°C
θVB for VBE
-2.0 -5.0 -20 -50 -100
Figure 11. Capacitance
VR, REVERSE VOLTAGE (VOLTS)
40
Figure 12. Current–Gain – Bandwidth Product
IC, COLLECTOR CURRENT (mA)
-0.1 -0.2 -1.0 -50
2.0 -2.0 -10 -100
100
200
500
50
20
20
10
6.0
4.0
-1.0 -10 -100
VCE = -5.0 V
C, CAPACITANCE (pF)
f, CURRENT-GAIN - BANDWIDTH PRODUCT
T
-0.5 -5.0 -20
TJ = 25°C
Cob
Cib
8.0
-50 mA -200 mA
BC856AWT1 Series, BC857BWT1 Series, BC858AWT1 Series
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Figure 13. Thermal Response
t, TIME (ms)
1.0
r(t), TRANSIENT THERMAL
2.0 5.01.00.50.20.1
RESISTANCE (NORMALIZED)
0.7
0.5
0.3
0.2
0.1
0.07
0.05
0.03
0.02
0.01
20 5010 200 500100 1.0k 2.0k 5.0k 10k
Figure 14. Active Region Safe Operating Area
VCE, COLLECTOR-EMITTER VOLTAGE (V)
-200
-1.0
IC, COLLECTOR CURRENT (mA)
TA = 25°C
D = 0.5
0.2
0.1 0.05 SINGLE PULSE
SINGLE PULSE
BONDING WIRE LIMIT
THERMAL LIMIT
SECOND BREAKDOWN LIMIT
3 ms
TJ = 25°C
ZθJC(t) = r(t) RθJC
RθJC = 83.3°C/W MAX
ZθJA(t) = r(t) RθJA
RθJA = 200°C/W MAX
D CURVES APPLY FOR POWER
PULSE TRAIN SHOWN
READ TIME AT t1
TJ(pk) – TC = P(pk) RθJC(t)
t1
t2
P(pk)
DUTY CYCLE, D = t1/t2
-100
-50
-10
-5.0
-2.0
-5.0 -10 -30 -45 -65 -100
1 s
BC858
BC857
BC856
The safe operating area curves indicate I C–VCE lim-
its of the transistor that must be observed for reliable op-
eration. Collector load lines for specific circuits must fall
below the limits indicated by the applicable curve.
The data of Figure 14 is based upon TJ(pk) = 150°C; TC
or TA is variable depending upon conditions. Pulse curves
are valid for duty cycles to 10% provided TJ(pk) 150°C.
TJ(pk) may be calculated from the data in Figure 13. At
high case or ambient temperatures, thermal limitations
will reduce the power that can be handled to values less
than the limitations imposed by the secondary breakdown.
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PD = TJ(max) – TA
RθJA
PD = 150°C – 25°C
0.625°C/W = 200 milliwatts
The soldering temperature and time should not exceed
260°C for more than 10 seconds.
When shifting from preheating to soldering, the
maximum temperature gradient should be 5°C or less.
After soldering has been completed, the device should
be allowed to cool naturally for at least three minutes.
Gradual cooling should be used as the use of forced
cooling will increase the temperature gradient and
result in latent failure due to mechanical stress.
Mechanical stress or shock should not be applied dur-
ing cooling
* Soldering a device without preheating can cause exces-
sive thermal shock and stress which can result in damage
to the device.
INFORMATION FOR USING THE SC–70/SOT–323 SURFACE MOUNT PACKAGE
MINIMUM RECOMMENDED FOOTPRINT FOR SURFACE MOUNTED APPLICATIONS
Surface mount board layout is a critical portion of the total
design. The footprint for the semiconductor packages must
be the correct size to insure proper solder connection
SC–70/SOT–323 POWER DISSIPATION
The power dissipation of the SC–70/SOT–323 is a func-
tion of the pad size. This can vary from the minimum pad
size for soldering to the pad size given for maximum power
dissipation. Power dissipation for a surface mount device
is determined by TJ(max), the maximum rated junction tem-
perature of the die, RθJA, the thermal resistance from the
device junction to ambient; and the operating temperature,
TA. Using the values provided on the data sheet, PD can be
calculated as follows.
The values for the equation are found in the maximum
ratings table on the data sheet. Substituting these values into
the equation for an ambient temperature TA of 25°C, one
can calculate the power dissipation of the device which in
this case is 200 milliwatts.
The 0.625°C/W assumes the use of the recommended
footprint on a glass epoxy printed circuit board to achieve
a power dissipation of 200 milliwatts. Another alternative
would be to use a ceramic substrate or an aluminum core
board such as Thermal Clad. Using a board material such
as Thermal Clad, a higher power dissipation of 300 milli-
watts can be achieved using the same footprint.
interface between the board and the package. With the
correct pad geometry, the packages will self align when
subjected to a solder reflow process.
SOLDERING PRECAUTIONS
The melting temperature of solder is higher than the rated
temperature of the device. When the entire device is heated
to a high temperature, failure to complete soldering within
a short time could result in device failure. Therefore, the
following items should always be observed in order to
minimize the thermal stress to which the devices are
subjected.
Always preheat the device.
The delta temperature between the preheat and
soldering should be 100°C or less.*
When preheating and soldering, the temperature of the
leads and the case must not exceed the maximum
temperature ratings as shown on the data sheet. When
using infrared heating with the reflow soldering
method, the difference should be a maximum of 10°C.
mm
inches
0.035
0.9
0.075
0.7
1.9
0.028
0.65
0.025
0.65
0.025
BC856AWT1 Series, BC857BWT1 Series, BC858AWT1 Series
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STEP 1
PREHEAT
ZONE 1
RAMP"
STEP 2
VENT
SOAK"
STEP 3
HEATING
ZONES 2 & 5
RAMP"
STEP 4
HEATING
ZONES 3 & 6
SOAK"
STEP 5
HEATING
ZONES 4 & 7
SPIKE"
STEP 6
VENT
STEP 7
COOLING
200°C
150°C
100°C
50°C
TIME (3 TO 7 MINUTES TOTAL) TMAX
SOLDER IS LIQUID FOR
40 TO 80 SECONDS
(DEPENDING ON
MASS OF ASSEMBLY)
205° TO 219°C
PEAK AT
SOLDER JOINT
DESIRED CURVE FOR LOW
MASS ASSEMBLIES
100°C
150°C
160°C
140°C
Figure 15. Typical Solder Heating Profile
DESIRED CURVE FOR HIGH
MASS ASSEMBLIES
170°C
For any given circuit board, there will be a group of
control settings that will give the desired heat pattern. The
operator must set temperatures for several heating zones,
and a figure for belt speed. Taken together, these control
settings make up a heating “profile” for that particular
circuit board. On machines controlled by a computer, the
computer remembers these profiles from one operating
session t o the next. Figure 7 shows a typical heating profile
for use when soldering a surface mount device to a printed
circuit board. This profile will vary among soldering
systems but it is a good starting point. Factors that can
affect the profile include the type of soldering system in
use, density and types of components on the board, type of
solder used, and the type of board or substrate material
being used. This profile shows temperature versus time.
SOLDER STENCIL GUIDELINES
Prior to placing surface mount components onto a printed
circuit board, solder paste must be applied to the pads. A
solder stencil is required to screen the optimum amount of
solder paste onto the footprint. The stencil is made of brass
or stainless steel with a typical thickness of 0.008 inches.
The stencil opening size for the surface mounted package
should be the same as the pad size on the printed circuit
board, i.e., a 1:1 registration.
TYPICAL SOLDER HEATING PROFILE
The line on the graph shows the actual temperature that
might be experienced on the surface of a test board at or
near a central solder joint. The two profiles are based on a
high density and a low density board. The Vitronics
SMD310 convection/infrared reflow soldering system was
used to generate this profile. The type of solder used was
62/36/2 Tin Lead Silver with a melting point between
177–189°C. When this type of furnace is used for solder
reflow work, the circuit boards and solder joints tend to
heat first. The components on the board are then heated by
conduction. The circuit board, because it has a lar ge surface
area, absorbs the thermal energy more efficiently, then
distributes this energy to the components. Because of this
effect, the main body of a component may be up to 30
degrees cooler than the adjacent solder joints.
BC856AWT1 Series, BC857BWT1 Series, BC858AWT1 Series
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PACKAGE DIMENSIONS
SOT–323/SC–70
CASE 419–02
ISSUE G
STYLE 3:
PIN 1. BASE
2. EMITTER
3. COLLECTOR
CRN
AL
D
G
V
SB
H
J
K
3
12
NOTES:
1. DIMENSIONING AND TOLERANCING PER ANSI
Y14.5M, 1982.
2. CONTROLLING DIMENSION: INCH.
DIM MIN MAX MIN MAX
MILLIMETERSINCHES
A0.071 0.087 1.80 2.20
B0.045 0.053 1.15 1.35
C0.035 0.049 0.90 1.25
D0.012 0.016 0.30 0.40
G0.047 0.055 1.20 1.40
H0.000 0.004 0.00 0.10
J0.004 0.010 0.10 0.25
K0.017 REF 0.425 REF
L0.026 BSC 0.650 BSC
N0.028 REF 0.700 REF
R0.031 0.039 0.80 1.00
S0.079 0.087 2.00 2.20
V0.012 0.016 0.30 0.40
0.05 (0.002)
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without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular
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including without limitation special, consequential or incidental damages. “Typical” parameters which may be provided in SCILLC data sheets and/or
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4–32–1 Nishi–Gotanda, Shinagawa–ku, Tokyo, Japan 141–0031
Phone: 81–3–5740–2700
Email: r14525@onsemi.com
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Sales Representative.
BC856AWT1/D
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