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ACT3704
TYPICAL APPLICATION CIRCUIT
Rev2, 26-Jul-07
12V Linear-Mode Battery Charger for Li+/Li-polymer Cells
FEATURES
• Internal High Voltage MOSFET
• Up to 12V Input Voltage
• ±0.5% Output Voltage Accuracy
• Charge Current Thermal Foldback
• Programmable Termination Voltage
• Programmable Fast Charge Current
• Programmable Charging Timer
• No Blocking Diode Required
• Low Reverse Leakage
• Preconditioning for Deeply Depleted Battery
• Low Quiescent Current Standby Mode
• Space-Saving, Thermally-Enhanced SOP-
8/EP, TDFN33-8
APPLICATIONS
• Mobile Phone
• Wireless Headsets
• Portable Media Players
• Cradle Chargers
• Portable Devices
GENERAL DESCRIPTION
The ACT3704 is a complete linear charging solution
for single cell Lithium Ion and Lithium Polymer bat-
teries. It incorporates an internal 12V power MOS-
FET for Constant-Current, Constant-Voltage control
(CC/CV).
The battery regulation voltage accuracy is ± 0.5%
and can be set to either 4.1V or 4.2V. The charge
current is programmed with an external resistor to a
maximum of 1A to minimize total charge time.
The reverse leakage current from the battery is less
than 1µA if the input adaptor is disconnected or if
there is a reverse battery connection. The ACT3704
is available in thermally-enhanced SOP-8/EP, and
TDFN33-8 packages to accommodate high charge
current operation and minimize total charging time.
ACT3704
Rev2, 26-Jul-07
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ORDERING INFORMATION
PART NUMBER TEMPERATURE RANGE PACKAGE PINS PACKING
ACT3704YH -40°C to 85°C SOP-8/EP 8 TUBE
ACT3704YH-T -40°C to 85°C SOP-8/EP 8 TAPE & REEL
ACT3704NH-T -40°C to 85°C TDFN33-8 8 TAPE & REEL
PIN DESCRIPTIONS
PIN NUMBER PIN NAME PIN DESCRIPTION
1 nEOC
Open-Drain Charge Status Indicator. nEOC is a high voltage output and can with-
stand up to 12V, allowing it to drive LEDs that are directly connected to IN or to a
lower voltage supply. nEOC features an internal 7mA current limit, allowing this
pin to directly drive an LED for a visual charge-status indicator. For a logic-level
charge status indicator, simply connect a 10kΩ or greater pull-up resistor between
nEOC and a suitable voltage supply.
2 ADJ
Charge Termination Voltage Adjust. Connect ADJ to G to select 4.10V termination
voltage or connect ADJ to IN to select 4.20V termination voltage.
3 IN
Power Input. IN can be withstand operating voltages of up to 12V. Bypass to G
with a 1µF or larger capacitor.
4 ISET
Charge Current Set. Program the maximum charge current by connecting a resis-
tor (RISET) between ISET and G. See the Charge Current Programming section for
more information.
5 TIMER Safety Timer program pin. Connect to capacitor CTIMER.
6 BAT
Charge Battery Output. Connect this pin to the positive terminal of the battery.
Bypass this pin as close as possible to IC with 1µF ceramic capacitor.
7 G Ground.
8 nSTAT
Open-Drain Charge Status Indicator. nSTAT can withstand up to 12V, allowing it
to drive LEDs that are directly connected to IN or to a lower voltage supply,
nSTAT features an internal 7mA current limit, allowing this pin to directly drive an
LED for a visual charge-status indicator. For a logic-level charge status indicator,
simply connect a 10kΩ or greater pullup resistor between nSTAT and a suitable
voltage supply.
EP EP
Exposed Pad. The exposed thermal pad should be connected to board ground
plane and G. The ground plane should include a large exposed copper pad under
the package to connect the entire pad for thermal dissipation (see package out-
line).
PIN CONFIGURATION
ACT3704
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ABSOLUTE MAXIMUM RATINGSc
ELECTRICAL CHARACTERISTICS
c: Do not exceed these limits to prevent damage to the device. Exposure to absolute maximum rating conditions for long periods may
affect device reliability.
(VIN = VTERM + 1V, VBAT = 3.6V, TA = 25°C, unless otherwise specified.)
PARAMETER CONDITIONS MIN TYP MAX UNIT
Input Supply Voltage, VIN 4.2 12 V
ADJ = G 4.079 4.1 4.121
V
TA = -40°C to 85°C 4.059 4.141
ADJ = IN 4.179 4.2 4.221
TA = -40°C to 85°C 4.158 4.242
Line Regulation VIN = VTERM + 1V to 12V, IBAT = 10mA 0.03 0.1 %/V
Load Regulation VIN = VTERM + 1V, IBAT = 10mA to 250mA 0.05 0.1 %
Precondition Threshold 2.55 2.75 2.95 V
Precondition Threshold Hysteresis 125 mV
Constant Current Adjust Range 100 1000 mA
Fast Charge Constant Current VBAT = 3.8V, RISET = 50k 0.45 0.51 0.57 A
Precondition Charge Current VBAT = 2.5V, RISET = 50k 51 mA
End-of-Charge Threshold RISET = 50k 51 mA
Charge Restart Threshold VBAT Falling VTERM - 0.1 V
PMOS On Resistance VBAT = 3.8V, IBAT = 100mA 0.7 1.2 Ω
UVLO Threshold IN Rising 3.8 4.0 4.2 V
UVLO Hysteresis IN Falling 1 V
BAT Reserve Leakage Current Input floating or charger disabled 0.4 4 µA
IN Supply Current Charger Standby 500 800 µA
IN Supply Current Charger Enable 0.7 2 mA
ADJ Voltage Threshold 1.7 V
Battery Termination Voltage,
VTERM
Thermal Regulation Threshold 120 °C
PARAMETER VALUE UNIT
IN, ADJ, nSTAT, nEOC to G -0.3 to 15 V
BAT to G -0.3 to 7 V
ISET, TIMER to G -0.3 to 6 V
ISET, TIMER Current ±5 mA
Junction to Ambient Thermal
Resistance (θJA)
SOP-8/EP 45 °C/W
TDFN33-8 36.7 °C/W
Maximum Power Dissipation SOP-8/EP 1.8 W
TDFN33-8 2 W
Maximum Junction Temperature 125 °C
Storage Temperature -65 to 150 °C
Lead Temperature (Soldering, 10 sec) 300 °C
ACT3704
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PARAMETER CONDITIONS MIN TYP MAX UNIT
nSTAT, nEOC Outputs
Sink Current VnSTAT = VnEOC = 2V 4 7 10 mA
Output Low Voltage ISINK = 1mA 0.4 V
Leakage Current VnSTAT = VnEOC = 12V 1 µA
Charge Current Setting
ISET Pin Voltage 1.15 1.20 1.25 V
IBAT to ISET Current Ratio 22 kA/A
Charge Timers
TIMER Frequency TIMER Floating 0.8 1.5 2.2 kHz
POR Start Delay 1 ms
Transition Out of Preconditioning Delay 0.1 ms
Current Rise Time Out of Preconditioning 300 µs
Normal Safety Timer CTIMER = 2.2nF 0.5 hr
Precondition Safety Timer CTIMER = 2.2nF 20 mins
Total Safety Timer CTIMER = 2.2nF 1 hr
Time to End of Charge CTIMER = 2.2nF 10 mins
ELECTRICAL CHARACTERISTICS CONT’D
(VIN = VTERM + 1V, VBAT = 3.6V, TA = 25°C, unless otherwise specified.)
ACT3704
Rev2, 26-Jul-07
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1000
TYPICAL PERFORMANCE CHARACTERISTICS
(VIN = 5V, TA = 25°C, unless otherwise specified.)
4.50
4.00
3.50
3.00
2.50
2.00
1.50
1.00
0.50
0.00
200 400 0 600 800
Battery Termination Voltage vs. Charge Current
IBAT (mA)
VTERM (V)
600
550
500
450
400
350
200
150
100
0
IBAT (mA)
300
250
50
1.0 2.0 0.5 3.0 3.5 4.5
VBAT (V)
4.0 2.5 1.5
Charge Current vs. Battery Termination Voltage
600
500
400
100
IBAT (mA)
300
200
6.5 8.5 4.5 12.5 14.5
VIN (V)
10.5
Charge Current vs. Supply Voltage
575
550
525
500
475
450
350
325
300
IBAT (mA)
425
400
375
3.00
VBAT (V)
Charge Current vs. Battery Voltage
275
3.10 3.20 3.30 3.40 3.50 3.60 3.70 3.80 3.90 4.00 4.10
1000
900
800
700
600
500
200
100
IBAT (mA)
400
300
50 100
0 250 300 350
RISET (k)
150
Charge Current vs. RISET
0
200
4.300
4.275
4.250
4.225
4.200
4.125
VTERM (V)
4.175
4.150
5.5 6.0 5.0 8.0 8.5 9.0
VIN (V)
6.5
Battery Termination Voltage vs. Supply Voltage
7.0 7.5
ACT3704-001
ACT3704-002 ACT3704-004
ACT3704-003 ACT3704-005
ACT3704-006
VIN = 5V
RISET = 27k
ADJ = G
VIN = 5V
RISET = 47k
ADJ = G
VIN = 5V
VBAT = 3.7V
RISET = 47k
VIN = 5V
RISET = 47k
ADJ = G
VIN = 5V
VBAT = 3.7V
ADJ = G
RISET = 47k
IBAT = 100mA
ADJ = IN
4.100
Thermal Regulation Circuitry Active
ACT3704
Rev2, 26-Jul-07
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TYPICAL PERFORMANCE CHARACTERISTICS CONT’D
(VIN = 5V, TA = 25°C, unless otherwise specified.)
Battery Termination Voltage vs. Temperature
4.120
4.110
4.090
Battery Termination Voltage VTERM (V)
4.100
50 75
Temperature (°C)
25 -25
Battery Termination Voltage vs. Temperature
550
530
510
470
IBAT (mA)
490
-20 0
-40 40
Temperature (°C)
20
Charge Current vs. Ambient Temperature
450
2.85
2.83
2.81
2.73
Precondition Threshold Voltage (V)
2.79
-40
Temperature (°C)
Precondition Threshold Voltage vs. Ambient Temperature
4.20
4.10
4.00
UVLO (V)
3.90
-15 -40 60 85
Temperature (°C)
10
Undervoltage Lockout Voltage vs. Temperature
3.80
35
ACT3704-007
ACT3704-008 ACT3704-010
ACT3704-009 ACT3704-0011
ACT3704-0012
4.220
4.210
4.200
4.190
4.180
0
4.080
-50
80 60
2.75
2.77
-20 0 20 40 60 80
VIN = 5V
RISET = 47k
ADJ = G
VIN = 5V
ADJ = G
VIN = 5V
RISET = 47k
ADJ = VIN
85
Battery Termination Voltage VTERM (V)
Temperature (°C)
50 75 25 -25 0 -50 85
2.70
2.71
-40
Internal Charge Timer Frequency vs. Temperature
Temperature (°C)
1.275
1.175
1.025
Frequency (kHz)
1.075
1.325
1.000
-15 10 35 60 85
1.125
1.225 VIN = 7V
VIN = 5V
VIN = 5V
ADJ = IN
ACT3704
Rev2, 26-Jul-07
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FUNCTIONAL BLOCK DIAGRAM
7mA
nSTAT
G
BAT
1V
CVAMP
CHARGE
CONTROL
OSCILLATOR
nEOC
TIMER
ISET
UVLO REG
REF VREF = 1.20V
Thermal
Foldback
TJ> 120°C
BODY
Q1
BAT
CCAMP
EOCCOMP
+
-
-
+
+
-
-
+
IN
7mA
ADJ ADJCTRL
ACT3704
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FUNCTIONAL DESCRIPTION
The ACT3704 is an intelligent, stand-alone Con-
stant-Current, Constant-Voltage control (CC/CV),
linear-mode, single-cell charger for Lithium-Based
cell chemistries. The device incorporates current
and voltage sense circuitry, an internal 12V power
MOSFET, a 120°C thermal-regulation loop that mini-
mizes total charge time, a complete state-machine
that implements charge safety features, and circuitry
that eliminates the reverse-blocking diode required
by conventional charger designs.
The ACT3704 features an accurate charge termina-
tion voltage, programmable fast-charge constant
current, and a programmable charge safety timeout
period. Other features include current-limited nSTAT
and nEOC outputs that can directly drive LED indi-
cators without external resistors or provide a logic-
level status signal to the host microprocessor.
CC/CV Regulation Loop
At the core of the ACT3704 is a CC/CV regulation
loop, which regulates either current or voltage as
necessary to ensure fast and safe charging of the
battery.
In a normal charge cycle, this loop regulates the cur-
rent to the value set by RISET. Charging continues at
this current until the battery voltage reaches the
charge termination voltage. At this point the CV loop
takes over, and charge current is allowed to de-
crease as necessary to maintain charging at the
charge termination voltage.
Setting The Charge Termination Voltage
The ACT3704 offers two pin-programmable battery
termination voltages; connect ADJ to G to select a
4.10V termination voltage, connect ADJ to IN (or to
a voltage greater than 1.4V) to select a 4.20V termi-
nation voltage.
Charge Current Programming
The maximum charging current is programmed by
an external resistor (RISET) connected from ISET to
G.
Calculate RISET as follows:
Where IBAT is Amps.
The voltage at ISET is fixed at 1.20V, and the maxi-
mum charge current at BAT is set by:
The RISET values in Table 1 are standard 1%. Note
that the actual charging current may be limited to a
current that is lower than the programmed fast-
charge current due to the ACT3704’s internal ther-
mal-regulation loop. See the Thermal Regulation
Loop section for more information.
Thermal Regulation Loop
The ACT3704 features an internal thermal regula-
tion loop that reduces the charging current as nec-
essary to ensure that the die temperature does not
rise beyond the thermal regulation threshold of
120°C. This feature protects the ACT3704 against
excessive junction temperature and makes the
ACT3704 more accommodating to aggressive ther-
mal designs. Note, however, that attention to good
thermal designs is required to achieve the fastest
possible charge time by maximizing charge current.
In order to account for the extended total charge
time resulting from operation in thermal regulation
mode, the charge timeout periods are extended
proportionally to the reduction in charge current. In
order to ensure a safe charge, the maximum time-
out periods are limited to 2x the room temperature
values.
The conditions that cause the ACT3704 to reduce
charge current in accordance to the internal thermal
regulation loop can be approximated by calculating
the power dissipated in the part. Most of the power
dissipation is generated from the internal charge
MOSFET (Q1 in the Functional Block Diagram).
The power dissipation is calculated to be approxi-
mately:
Table 1:
Charge Current Programming
RISET(kΩ) Charge Current (mA)
89 297
64 413
56 470
47 562
33 800
27 989
()
ISETBAT R/V20.1Ωk22I ×= (2)
()
BATISET I/V20.1Ωk22R ×= (1)
(
)
BATBATIND IV-VP
×
=
(3)
PD is the power dissipated, VIN is the input supply
voltage, VBAT is the battery voltage and IBAT is the
charge current. The approximate ambient tempera-
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()
JABATBATINA IV-V-C120T
θ
××°=
()()
C45mA7003.4V-5V-C120TA°×
×
°=
C6.69T A°=
()
()
A/C72
C50
W/C453.4V-V5
C70-C120
IBAT °
°
=
°×
°°
=
mA694TA=
(4)
(5)
(6)
(7)
Example: The ACT3704 is operating from a 5V wall
adapter and is programmed to supply 700mA fast
charge current to a discharged Li-Ion battery with a
voltage of 3.4V. Assuming θJA is 45°C/W, the ambi-
ent temperature at which the device will begin to
reduce the charge current is approximately:
The ACT3704 can be used above 69.6°C ambient,
but the charge current will be reduced from 700mA.
The approximate current at a given ambient tem-
perature can be approximated by:
Using the previous example with an ambient tem-
perature of 70°C, the charge current will be reduced
to approximately:
ACT3704 applications do not need to be designed
for worst-case thermal conditions, since the part will
automatically reduce power dissipation if the ther-
mal regulation threshold of approximately 120°C is
reached.
However, in order to deliver maximum charge cur-
rent under all conditions, it is critical that the ex-
posed metal pad on the backside of the package
exposed pad (EP) is soldered directly to the PC
board ground. Correctly soldered to a double sided
1oz copper board, the ACT3704 has a thermal re-
sistance of approximately 45°C/W with SOP8 and
36.7°C/W with TDFN33-8. Failure to make thermal
contact between the exposed pad on the backside
pf the package and the copper board will result in
thermal resistances far greater than 45°C/W with
SOP8 and 36.7°C/W with TDFN33-8. For example,
a correctly soldered ACT3704 can deliver up to
()
()
JABATIN
A
BAT VV
TC120
I
θ
×−
−°
=
C4.50C120C45W12.1C120TA°−°=°×−°=
JADA PC120T
θ
×−°=
1000mA to a battery from a 5V supply at 25°C.
Without a good backside thermal connection, this
number could drop to less than 500mA.
State Machine
Precondition State
A new charging cycle begins with the PRECONDI-
TION state, and operation continues in this state
until VBAT exceeds the Precondition Threshold Volt-
age of 2.8V.
When operating in PRECONDITION state, the cell
is charged at a reduced current given by:
Which is 10% of the programmed maximum fast-
charge constant current, IBAT.
Once VBAT reaches the Precondition Threshold Volt-
age the state machine jumps to the NORMAL state.
If VBAT does not reach the Precondition Threshold
Voltage before the Precondition Timeout period
(TPRECONDITION) expires, then a damaged cell is de-
tected and the state machine jumps to the TIME-
OUT-FAULT State. The Precondition Timeout pe-
riod is default to 20mins with an external 2.2nF
CTIMER capacitor, or it can be increased with a larger
value capacitor. See the Safely Timers section for
more information.
Normal State
Normal state is made up of two operating modes,
fast charge Constant-Current (CC) and Constant-
Voltage (CV).
In CC mode, the ACT3704 charges at the current
programmed by RISET (see the Charge Current Pro-
gramming section for more information). During a
normal charge cycle fast-charge continues in CC
mode until VBAT reaches the charge termination volt-
age (VTERM), at which point the ACT3704 charges in
CV mode. Charging continues in CV mode until the
charge current drops to 10% of the programmed
maximum charge current (IBAT), at which point the
state machine jumps to the TOP-OFF state.
If VBAT does not proceed out of the NORMAL state
before the Normal Timeout period (TNORMAL) expires,
then a damaged cell is detected and the state ma-
chine jumps to the TIMEOUT-FAULT State.
The Normal Timeout period is default to 30mins, or
it can be increased with an external 2.2nF CTIMER
capacitor or can be changed with a larger value
external capacitor. See the Safety Times section for
more information.
ture at which the thermal regulation begins to pro-
tect the IC is given by :
(8)
(
)
ISETISETONPRECONDITI R/V200.2I
×
=
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Top-Off State
In the TOP-OFF state, the cell is charged in con-
stant-voltage (CV) mode, with the charge current
limited by the internal chemistry of the cell, decreas-
ing as charging continues.
If the ACT3704 state machine does not complete a
charging cycle before the TOP-OFF Timeout period
(TTOPOFF) expires, then a damaged cell is detected
and the state machine jumps to the TIMEOUT-
FAULT State.
The TOP-OFF Timeout period is default to 60mins
with a 2.2nF CTIMER capacitor, or it can be increased
with a larger value external capacitor. See the
Safety Timers section for more information.
In TOP-OFF state, nSTAT indicates charge com-
plete but charge current still continues. After another
delay of 60mins, then charging stops and charge
current becomes zero. When the battery voltage
drops below the charge restart voltage, the charging
process will start again.
End of Charge State
In the End of Charge (EOC) state, the ACT3704
presents a high-impedance to the battery, allowing
the cell to “relax” and minimize battery leakage cur-
rent. The ACT3704 continues to monitor the cell
voltage, however, so that it can reinitiate charging
cycles as necessary to ensure that the cell remains
fully charged.
Charge Restart
Under normal operation, the state machine initiates
a new charging cycle by jumping to the NORMAL
CHARGE state when VBAT drops below the Charge
Termination Threshold by more than the Charge Re-
start Threshold of 100mV (typ).
Timeout-Fault State
In TIMEOUT-FAULT state, both nSTAT and nEOC
indicators are OFF, or high-Z.
Charge and EOC Status Outputs
nSTAT and nEOC are open-drain outputs that sink
current when asserted and are high-Z otherwise. For
more information regarding the state of nSTAT and
nEOC throughout the entire charging cycle, see Ta-
ble 3. These outputs have internal 7mA current lim-
its, and are capable of directly driving LEDs, without
the need of current-limiting resistors or other exter-
nal circuitry, for a visual charge-status indication. To
drive an LED, simply connect the LED between
each pin and an appropriate supply (typically VIN).
For a logic-level indication, simply connect a resistor
from each output to an appropriate voltage supply.
Reverse Battery & Shutdown
The ACT3704 includes internal circuitry that elimi-
nates the need for series blocking diodes, reducing
solution size and cost as well as dropout voltage
relative to conventional battery chargers. When VIN
goes below the ACT3704’s under voltage-lockout
(UVLO) voltage, or when VIN drops below VBAT, the
ACT3704 automatically goes into SUSPEND mode
and reconfigures its power switch to minimize cur-
rent drain from the battery.
Safety Timers
The ACT3704 has several internal charge safety
timers, for each of the PRECONDITION and NOR-
MAL charge states as well as TOPOFF timeout pe-
riod. If any of these timers expire before charge suc-
cessfully proceeds through the associated state, the
ACT3704 enters the TIMEOUT-FAULT state. The
TIMEOUT-FAULT state can only be reset by power-
cycling the ACT3704.
Each of these timers are internally set according to
the following ratios:
All the timers could be set by an external capacitor
by (CTIMER in nF) where TO is given by:
When operating in thermal regulation mode the
timeout periods are extended in order to compen-
sate for the effect of the reduced charging current
on total charge time. In order to ensure a safe
charge, the maximum timeout periods are limited to
2x the room temperature values.
OONPRECONDITI T1T
×
=
ONORMAL T5.1T
×
=
OTOTAL T3T
×
=
%15C9T TIMERO
±
×
=
(9)
(10)
(11)
(12)
ACT3704
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Table 2:
Safety Timer Settings
CTIMER
(nF)
TPRECONDITION
(minutes)
TNORMAL
(minutes)
TTOTAL
(minutes)
2.2 20 30 60
3.3 30 45 90
6 60 90 180
10 90 120 270
30 210 315 630
STATE DIAGRAM
ANY STATE
SUSPEND
PRECONDITION
NORMAL
TOP OFF
END OF CHARGE
VIN < 4.0V
VIN > 4.0V
VBAT < 2.7V
VBAT < VTERM -0.1V
Time > TTOTAL
VBAT = VREG
Time > TNORMAL
VBAT > 2.8V
Time > TPRECONDITION
TIMEOUT-FAULT
VBAT < VREG
IBAT < 10% ICHRG
and T > TEOC
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STATUS AND EOC INDICATORS
Table 3:
nSTAT and nEOC Indicator States
STATE nSTAT nEOC
SHUTDOWN OFF OFF
PRECONDITION ON OFF
NORMAL ON OFF
TOPOFF ON OFF
END OF CHARGE OFF ON
TIMEOUT FAULT OFF OFF
DELAY TIME TO EOC OFF ON
Figure 1:
Typical Li+ Charge Profile and ACT3704 Charge States
VTERM
IBAT
VPRECONDITION
IPRECONDITION, IEOC
A B C D
4.20V
510mA
2.75V
51mA
A: PRECONDITION State
B: NORMAL State
C: TOP-OFF State
D: END OF CHARGE State
Current
Voltage
STATE
TEOC
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APPLICATION INFORMATION
Figure 2:
Application Circuit for 4.1V Battery, 470mA Charge
Figure 3:
Application Circuit for 4.2V Battery, 800mA Charge
CIN
10µF
RISET
56k
nEOC
ADJ
IN
ISET
nSTAT
BAT
TIMER
G
VIN
CTIMER = 10nF CBAT
1µF
Li+ or
Li-POLYMER
BATTERY
ACT3704
ACT3704
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SYMBOL
DIMENSION IN
MILLIMETERS
DIMENSION IN
INCHES
MIN MAX MIN MAX
A 1.350 1.750 0.053 0.069
A1 0.050 0.150 0.002 0.006
A2 1.350 1.550 0.053 0.061
b 0.330 0.510 0.013 0.020
c 0.170 0.250 0.007 0.010
D 4.700 5.100 0.185 0.200
D1 3.202 3.402 0.126 0.134
E 3.800 4.000 0.150 0.157
E1 5.800 6.200 0.228 0.244
E2 2.313 2.513 0.091 0.099
e 1.270 TYP 0.050 TYP
L 0.400 1.270 0.016 0.050
θ 0° 8° 0° 8°
PACKAGE OUTLINE
SOP-8/EP PACKAGE OUTLINE AND DIMENSIONS
D1
b
D
e
ACT3704
Rev2, 26-Jul-07
Innovative Products. Active Solutions. - 15 - www.active-semi.com
Copyright © 2007 Active-Semi, Inc.
PACKAGE OUTLINE
TDFN33-8 PACKAGE OUTLINE AND DIMENSIONS
SYMBOL
DIMENSION IN
MILLIMETERS
DIMENSION IN
INCHES
MIN MAX MIN MAX
A 0.700 0.800 0.028 0.031
A1 0.000 0.050 0.000 0.002
A3 0.153 0.006
D 2.900 3.100 0.114 0.122
E 2.900 0.114
D2 2.200 0.087
E2 0.055
b 0.200 0.320 0.008 0.013
e 0.650 TYP 0.026 TYP
L 0.375 0.575 0.015 0.023
1.400
3.100 0.122
0.253 0.010
2.400
1.600
0.094
0.063
