TI TL2843BDR-8

TL284xB, TL384xB
HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
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FEATURES
•
•
•
•
•
•
•
•
Low Start-Up Current (<0.5 mA)
Trimmed Oscillator Discharge Current
Current Mode Operation to 500 kHz
Automatic Feed-Forward Compensation
Latching PWM for Cycle-by-Cycle Current
Limiting
Internally Trimmed Reference With
Undervoltage Lockout
High-Current Totem-Pole Output
Undervoltage Lockout With Hysteresis
Double-Pulse Suppression
SLVS610A – AUGUST 2006 – REVISED SEPTEMBER 2006
D (SOIC) OR P (PDIP) PACKAGE
(TOP VIEW)
COMP
VFB
ISENSE
RT/CT
1
8
2
7
3
6
4
5
VREF
VCC
OUTPUT
GND
D (SOIC) PACKAGE
(TOP VIEW)
COMP
NC
VFB
NC
ISENSE
NC
RT/CT
1
14
2
13
3
12
4
11
5
10
6
7
9
8
VREF
NC
VCC
VC
OUTPUT
GND
POWER GROUND
NC − No internal connection
DESCRIPTION/ORDERING INFORMATION
The TL284xB and TL384xB series of control integrated circuits provide the features that are necessary to
implement off-line or dc-to-dc fixed-frequency current-mode control schemes, with a minimum number of
external components. Internally implemented circuits include an undervoltage lockout (UVLO) and a precision
reference that is trimmed for accuracy at the error amplifier input. Other internal circuits include logic to ensure
latched operation, a pulse-width modulation (PWM) comparator that also provides current-limit control, and a
totem-pole output stage designed to source or sink high-peak current. The output stage, suitable for driving
N-channel MOSFETs, is low when it is in the off state.
The TL284xB and TL384xB series are pin compatible with the standard TL284x and TL384x with the following
improvements. The start-up current is specified to be 0.5 mA (max), while the oscillator discharge current is
trimmed to 8.3 mA (typ). In addition, during undervoltage lockout conditions, the output has a maximum
saturation voltage of 1.2 V while sinking 10 mA (VCC = 5 V).
Major differences between members of these series are the UVLO thresholds and maximum duty-cycle ranges.
Typical UVLO thresholds of 16 V (on) and 10 V (off) on the TLx842B and TLx844B devices make them ideally
suited to off-line applications. The corresponding typical thresholds for the TLx843B and TLx845B devices are
8.4 V (on) and 7.6 V (off). The TLx842B and TLx843B devices can operate to duty cycles approaching 100%. A
duty-cycle range of 0% to 50% is obtained by the TLx844B and TLx845B by the addition of an internal toggle
flip-flop, which blanks the output off every other clock cycle.The TL284xB-series devices are characterized for
operation from –40°C to 85°C. The TL384xB-series devices are characterized for operation from 0°C to 70°C.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2006, Texas Instruments Incorporated
TL284xB, TL384xB
HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
www.ti.com
SLVS610A – AUGUST 2006 – REVISED SEPTEMBER 2006
ORDERING INFORMATION
PACKAGE (1)
TA
PDIP – P
SOIC – D (8 pin)
–40°C to 85°C
SOIC – D (14 pin)
PDIP – P
SOIC – D (8 pin)
0°C to 70°C
SOIC – D (14 pin)
(1)
2
ORDERABLE PART NUMBER
Tube of 50
TL2842BP
TL2842BP
TL2843BP
TL2843BP
TL2844BP
TL2844BP
TL2845BP
TL2845BP
Tube of 75
TL2842BD-8
Reel of 2500
TL2842BDR-8
Tube of 75
TL2843BD-8
Reel of 2500
TL2843BDR-8
Tube of 75
TL2844BD-8
Reel of 2500
TL2844BDR-8
Tube of 75
TL2845BD-8
Reel of 2500
TL2845BDR-8
Tube of 75
TL2842BD
Reel of 2500
TL2842BDR
Tube of 75
TL2843BD
Reel of 2500
TL2843BDR
Tube of 75
TL2844BD
Reel of 2500
TL2844BDR
Tube of 75
TL2845BD
Reel of 2500
TL2845BDR
Tube of 50
TOP-SIDE MARKING
2842B
2843B
2844B
2845B
TL2842B
TL2843B
TL2844B
TL2845B
TL3842BP
TL3842BP
TL3843BP
TL3843BP
TL3844BP
TL3844BP
TL3845BP
TL3845BP
Tube of 75
TL3842BD-8
Reel of 2500
TL3842BDR-8
Tube of 75
TL3843BD-8
Reel of 2500
TL3843BDR-8
Tube of 75
TL3844BD-8
Reel of 2500
TL3844BDR-8
Tube of 75
TL3845BD-8
Reel of 2500
TL3845BDR-8
Tube of 75
TL3842BD
Reel of 2500
TL3842BDR
Tube of 75
TL3843BD
Reel of 2500
TL3843BDR
Tube of 75
TL3844BD
Reel of 2500
TL3844BDR
Tube of 75
TL3845BD
Reel of 2500
TL3845BDR
3842B
3843B
3844B
3845B
TL3842B
TL3843B
TL3844B
TL3845B
Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at
www.ti.com/sc/package.
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TL284xB, TL384xB
HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
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SLVS610A – AUGUST 2006 – REVISED SEPTEMBER 2006
FUNCTIONAL BLOCK DIAGRAM
VCC
7
34 V NOM
GND
UVLO
5
−
5-V VREF
8
EN
+
VREF
Internal
Bias
2.5 V
VREF
Good
Logic
RT/CT
4
6
OSC
OUTPUT
T
Error
Amplifier
VFB
COMP
ISENSE
A.
2
1
+
−
S
2R
R
R
3
1V
PWM
Latch
CurrentSense
Comparator
Pin numbers shown are for the 8-pin D package.
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TL284xB, TL384xB
HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
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SLVS610A – AUGUST 2006 – REVISED SEPTEMBER 2006
Absolute Maximum Ratings (1) (2)
over operating free-air temperature range (unless otherwise noted)
MIN
Low impedance source
MAX
UNIT
30
VCC
Supply voltage
VI
Analog input voltage range
6.3
V
ICC
Supply current
30
mA
IO
Output current
±1
A
IO(sink)
Error amplifier output sink current
10
mA
θJA
Package thermal impedance (3) (4)
Self
limiting
ICC < 30 mA
VFB and ISENSE
D package
–0.3
8 pin
97
14 pin
86
P package
Output energy
TJ
Virtual junction temperature
Tstg
Storage temperature range
Tlead
Lead temperature
(1)
(2)
(3)
(4)
V
°C/W
85
Capacitive load
–65
Soldering, 10 s
5
µJ
150
°C
150
°C
300
°C
Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings
only, and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating
conditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
All voltages are with respect to the device GND terminal.
Maximum power dissipation is a function of TJ(max), θJA, and TA. The maximum allowable power dissipation at any allowable ambient
temperature is PD = (TJ(max) – TA)/θJA. Operating at the absolute maximum TJ of 150°C can impact reliability.
The package thermal impedance is calculated in accordance with JESD 51-7.
Recommended Operating Conditions
MIN
VCC
Supply voltage
VI
Input voltage
VO
Output voltage
ICC
Supply current, externally limited
IO
IO(ref)
fosc
Oscillator frequency
TJ
Operating free-air temperature
(1)
4
NOM
MAX
VCC
30
VC (1)
30
RT/CT
0
5.5
VFB and ISENSE
0
5.5
0
30
–0.1
1
OUTPUT
POWER GROUND (1)
UNIT
V
V
V
25
mA
Average output current
200
mA
Reference output current
–20
mA
500
kHz
100
TL284xB
–40
85
TL384xB
0
70
The recommended voltages for VC and POWER GROUND apply only to the 14-pin D package.
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°C
TL284xB, TL384xB
HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
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SLVS610A – AUGUST 2006 – REVISED SEPTEMBER 2006
Reference Section Electrical Characteristics
VCC = 15 V (1), RT = 10 kΩ, CT = 3.3 nF, over recommended operating free-air temperature range (unless otherwise specified)
PARAMETER
TEST CONDITIONS
TL284xB
TL384xB
UNIT
MIN
TYP (2)
MAX
MIN
TYP (2)
MAX
4.95
5
5.05
4.9
5
5.1
V
Output voltage
IO = 1 mA, TJ = 25°C
Line regulation
VCC = 12 V to 25 V
6
20
6
20
mV
Load regulation
IO = 1 mA to 20 mA
6
25
6
25
mV
0.2
0.4
0.2
0.4
mV/°C
5.18
V
Average temperature
coefficient of output voltage
Output voltage, worst-case
variation
VCC = 12 V to 25 V,
IO = 1 mA to 20 mA
Output noise voltage
f = 10 Hz to 10 kHz, TJ = 25°C
4.9
(1)
(2)
4.82
50
Output-voltage long-term drift After 1000 h at TJ = 25°C
Short-circuit output current
5.1
–30
µV
50
5
25
–100
–180
–30
5
25
mV
–100
–180
mA
Adjust VCC above the start threshold before setting it to 15 V.
All typical values are at TJ = 25°C.
Oscillator Section (1) Electrical Characteristics
VCC = 15 V (2), RT = 10 kΩ, CT = 3.3 nF, over recommended operating free-air temperature range (unless otherwise specified)
PARAMETER
Initial accuracy
Voltage stability
TEST CONDITIONS
TL284xB
MIN
MAX
MIN
TYP (3)
MAX
TJ = 25°C, RT = 62 kΩ,
CT = 1 nF, Min = 225 kHz,
Max = 275 kHz
49
52
55
49
52
55
TJ = Full range
48
56
48
VCC = 12 V to 25 V
0.2
Temperature stability
Amplitude
Discharge current
(1)
(2)
(3)
TL384xB
TYP (3)
1
Peak to peak
7.8
RT/CT = 2 V
7.5
8.3
1
5
1.7
TJ = 25°C, RT/CT = 2 V
7.8
8.8
7.6
8.3
%
%
1.7
8.8
kHz
56
0.2
5
UNIT
V
8.8
8.8
mA
Output frequency equals oscillator frequency for the TL3842B and TL3843B. Output frequency is one-half the oscillator frequency for the
TL3844B and TL3845B.
Adjust VCC above the start threshold before setting it to 15 V.
All typical values are at TJ = 25°C.
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HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
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SLVS610A – AUGUST 2006 – REVISED SEPTEMBER 2006
Error-Amplifier Section Electrical Characteristics
VCC = 15 V (1), RT = 10 kΩ, CT = 3.3 nF, over recommended operating free-air temperature range (unless otherwise specified)
PARAMETER
Feedback input voltage
TEST CONDITIONS
COMP = 2.5 V
TL284xB
UNIT
TYP (2)
MAX
MIN
TYP (2)
MAX
2.45
2.5
2.55
2.42
2.5
2.58
V
–0.3
–1
–0.3
–2
µA
Input bias current
Open-loop voltage
amplification
TL384xB
MIN
VO = 2 V to 4 V
65
90
65
90
dB
MHz
Gain-bandwidth product
0.7
1
0.7
1
Supply-voltage rejection ratio VCC = 12 V to 25 V
60
70
60
70
dB
2
6
2
6
mA
–0.5
–0.8
–0.5
–0.8
mA
5
6
5
6
Output sink current
VFB = 2.7 V, COMP = 1.1 V
Output source current
VFB = 2.3 V, COMP = 5 V
High-level output voltage
VFB = 2.3 V,
RL = 15 kΩ to GND
Low-level output voltage
VFB = 2.7 V,
RL = 15 kΩ to GND
(1)
(2)
0.7
1.1
0.7
V
1.1
V
Adjust VCC above the start threshold before setting it to 15 V.
All typical values are at TJ = 25°C.
Current-Sense Section Electrical Characteristics
VCC = 15 V (1), RT = 10 kΩ, CT = 3.3 nF, over recommended operating free-air temperature range (unless otherwise specified)
PARAMETER
TEST CONDITIONS
Voltage amplification (3) (4)
Current-sense comparator
threshold (3)
COMP = 5 V
Supply-voltage rejection
ratio (3)
VCC = 12 V to 25 V
Input bias current
Delay time to output
(1)
(2)
(3)
(4)
6
VFB = 0 V to 2 V
TL284xB
TL384xB
UNIT
MIN
TYP (2)
MAX
MIN
TYP (2)
MAX
2.85
3
3.15
2.85
3
3.15
V/V
0.9
1
1.1
0.9
1
1.1
V
70
70
dB
–2
–10
–2
–10
µA
150
300
150
300
ns
Adjust VCC above the start threshold before setting it to 15 V.
All typical values are at TJ = 25°C.
Measured at the trip point of the latch, with VFB at 0 V.
Measured between ISENSE and COMP, with the input changing from 0 V to 0.8 V.
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HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
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SLVS610A – AUGUST 2006 – REVISED SEPTEMBER 2006
Output Section Electrical Characteristics
VCC = 15 V (1), RT = 10 kΩ, CT = 3.3 nF, over recommended operating free-air temperature range (unless otherwise specified)
PARAMETER
High-level output voltage
TEST CONDITIONS
TL284xB
MIN
TYP (2)
IOH = –20 mA
13
IOH = –200 mA
12
TL384xB
MIN
TYP (2)
13.5
13
13.5
13.5
12
13.5
MAX
MAX
UNIT
V
IOL = 20 mA
0.1
0.4
0.1
0.4
IOL = 200 mA
1.5
2.2
1.5
2.2
Rise time
CL = 1 nF, TJ = 25°C
50
150
50
150
ns
Fall time
CL = 1 nF, TJ = 25°C
50
150
50
150
ns
UVLO saturation
VCC = 5 V, IOL = 1 mA
0.7
1.2
0.7
1.2
V
Low-level output voltage
(1)
(2)
V
Adjust VCC above the start threshold before setting it to 15 V.
All typical values are at TJ = 25°C.
Undervoltage-Lockout Section Electrical Characteristics
VCC = 15 V (1), RT = 10 kΩ, CT = 3.3 nF, over recommended operating free-air temperature range (unless otherwise specified)
PARAMETER
Start threshold voltage
Minimum operating voltage
after start-up
(1)
(2)
TEST CONDITIONS
TL284xB
TL384xB
MIN
TYP (2)
MAX
MIN
TYP (2)
MAX
TLx842B, TLx844B
15
16
17
14.5
16
17.5
TLx843B, TLx845B
7.8
8.4
9
7.8
8.4
9
TLx842B, TLx844B
9
10
11
8.5
10
11.5
TLx843B, TLx845B
7
7.6
8.2
7
7.6
8.2
UNIT
V
V
Adjust VCC above the start threshold before setting it to 15 V.
All typical values are at TJ = 25°C.
Pulse-Width Modulator Section Electrical Characteristics
VCC = 15 V (1), RT = 10 kΩ, CT = 3.3 nF, over recommended operating free-air temperature range (unless otherwise specified)
PARAMETER
Maximum duty cycle
TEST CONDITIONS
TL284xB
TYP (2)
MAX
MIN
TYP (2)
MAX
TL3842B, TL3843B
94
96
100
94
96
100
TL3844B, TL3845B
47
48
50
47
48
50
Minimum duty cycle
(1)
(2)
TL384xB
MIN
0
0
UNIT
%
%
Adjust VCC above the start threshold before setting it to 15 V.
All typical values are at TJ = 25°C.
Supply Voltage Electrical Characteristics
VCC = 15 V (1), RT = 10 kΩ, CT = 3.3 nF, over recommended operating free-air temperature range (unless otherwise specified)
PARAMETER
TEST CONDITIONS
TL284xB
MIN
Start-up current
Operating supply current
VFB and ISENSE at 0 V
Limiting voltage
ICC = 25 mA
(1)
(2)
30
TL384xB
TYP (2)
MAX
0.3
11
34
UNIT
TYP (2)
MAX
0.5
0.3
0.5
mA
17
11
17
mA
MIN
30
34
V
Adjust VCC above the start threshold before setting it to 15 V.
All typical values are at TJ = 25°C.
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HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
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SLVS610A – AUGUST 2006 – REVISED SEPTEMBER 2006
TYPICAL CHARACTERISTICS
AVOL – Open-Loop Voltage Gain – dB
25
15
5
TL2842
10
TL2845
ICC – Supply Current – mA
20
100
200
80
150
60
Phase
40
50
20
0
Gain
VCC = 15 V
0
-50
kΩ
RL = 100 kX
TA = 25°C
-20
0
1 . E +0 1
0
5
10
15
20
25
30
35
100
Phase Margin – deg
ERROR AMPLIFIER OPEN-LOOP
GAIN AND PHASE
vs
FREQUENCY
SUPPLY CURRENT
vs
SUPPLY VOLTAGE
10
40
1 . E +0 2
100
1 . E +0 3
1 . E +0 4
1 . E +0 5
10k 100k
1k
f – Frequency – Hz
1 . E +0 6
1M
-100
10M
1 . E +0 7
VCC – Supply Voltage – V
CURRENT-SENSE INPUT THRESHOLD
vs
ERROR AMPLIFIER OUTPUT VOLTAGE
OSCILLATOR DISCHARGE CURRENT
vs
TEMPERATURE
9.2
VIN = 15 V
Idisharge – Oscillator Discharge Current – mA
Vth – Current-Sense Input Threshold – V
1.2
1
0.8
TA = 125°C
0.6
TA = 25°C
0.4
TA = -55°C
0.2
0
0
1
2
3
4
5
6
7
8
VOSC = 2 V
8.8
8.6
8.4
8.2
8
7.8
7.6
7.4
-55 -35 -15
VO – Error Amplifier Output Voltage – V
8
VIN = 15 V
9
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5
25
45
65
85 105 125 145
TA – Temperature – °C
TL284xB, TL384xB
HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
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SLVS610A – AUGUST 2006 – REVISED SEPTEMBER 2006
TYPICAL CHARACTERISTICS (continued)
REFERENCE VOLTAGE
vs
SOURCE CURRENT
REFERENCE VOLTAGE
vs
TEMPERATURE
5.2
0
5.15
Vref – Reference Voltage – V
Reference Voltage Delta – mV
-10
-20
TA = -40°C
-30
TA = 125°C
-40
TA = 25°C
-50
5.1
5.05
5
4.95
4.9
4.85
-60
0
20
40
60
80
100
120
140
4.8
-55
160
-30
-5
Isrc – Source Current – mA
20
45
70
95
120
145
TA – Temperature – °C
REFERENCE SHORT-CIRCUIT CURRENT
vs
TEMPERATURE
OUTPUT SATURATION VOLTAGE
vs
LOAD CURRENT
10
180
VIN = 15 V
0
Source Saturation
TA = 25°C
9
-1
8
Sink Saturation Voltage – V
ISC – Short-Circuit Current – mA
160
140
120
100
80
-2
TA = -55°C
7
-3
6
-4
5
-5
4
-6
Sink Saturation
3
2
-8
60
TA = 25°C
1
40
-55
-7
TA = -55°C
-9
0
-30
-5
20
45
70
95
120
145
0
100
200
300
400
500
600
700
-10
800
IO – Output Load Current – mA
TA – Temperature – °C
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HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
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SLVS610A – AUGUST 2006 – REVISED SEPTEMBER 2006
TYPICAL CHARACTERISTICS (continued)
MAXIMUM OUTPUT DUTY CYCLE
vs
TIMING RESISTOR
100
Dmax – Maximum Duty Cycle – %
VCC = 15 V
CT = 3.3 nF
90
TA = 25°C
80
70
60
50
40
0.1
1
kΩ
RT – Timing Resistor – k€
OUTPUT WAVEFORM
10
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10
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HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
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SLVS610A – AUGUST 2006 – REVISED SEPTEMBER 2006
APPLICATION INFORMATION
The error-amplifier configuation circuit is shown in Figure 1.
2.5 V
0.5 mA
Error
Amplifier
VFB
Zi
COMP
Zf
A.
+
−
Error amplifier can source or sink up to 0.5 mA.
Figure 1. Error-Amplifier Configuration
The current-sense circuit is shown in Figure 2.
Error
Amplifier
IS
(see Note A)
2R
+
−
R
COMP
Rf
RS
1V
Current-Sense
Comparator
ISENSE
Cf
GND
A.
Peak current (IS) is determined by the formula: IS(max) = 1 V/RS
B.
A small RC filter formed by resistor Rf and capacitor Cf may be required to suppress switch transients.
Figure 2. Current-Sense Circuit
The oscillator frequency is set using the circuit shown in Figure 3. The frequency is calculated as:
f = 1 / RTCT
For RT > 5 kΩ:
f ≈ 1.72 / RTCT
VREF
RT
RT/CT
CT
GND
Figure 3. Oscillator Section
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HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
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SLVS610A – AUGUST 2006 – REVISED SEPTEMBER 2006
APPLICATION INFORMATION (continued)
TIMING RESISTANCE
vs
FREQUENCY
DEAD TIME
vs
TIMING CAPACITANCE
100
100
CT = 10 nF
VCC = 15 V
RT ≥ 5 kΩ
TA = 25°C
40
CT = 4.7 nF
CT = 22 nF
R T − Timing Resistance − k Ω
Dead Time − µ s
40
10
4
1
CT = 1 nF
CT = 22 nF
10
CT = 47 nF
CT = 100 nF
4
0.4
VCC = 15 V
TA = 25°C
1
100
0.1
0
4
10
40
100
1k
10k
100k
1M
f − Frequency − Hz
CT − Timing Capacitance − nF
Open-Loop Laboratory Test Fixture
In the open-loop laboratory test fixture (see Figure 4), high peak currents associated with loads necessitate
careful grounding techniques. Timing and bypass capacitors should be connected close to the GND terminal in a
single-point ground. The transistor and 5-kΩ potentiometer sample the oscillator waveform and apply an
adjustable ramp to the ISENSE terminal.
REF
RT
A
4.7 kΩ
VCC
2N2222
100 kΩ
1-kΩ
Error Amplifier Adjust
VFB
5 kΩ
VREF
COMP
TL284xB
TL384xB
0.1 µF
VCC
0.1 µF
ISENSE
OUTPUT
1 kΩ, 1 W
OUTPUT
4.7 kΩ
ISENSE
Adjust
RT/CT
GND
GND
CT
Figure 4. Open-Loop Laboratory Test Fixture
12
Submit Documentation Feedback
TL284xB, TL384xB
HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
www.ti.com
SLVS610A – AUGUST 2006 – REVISED SEPTEMBER 2006
APPLICATION INFORMATION (continued)
Shutdown Technique
The PWM controller (see Figure 5) can be shut down by two methods: either raise the voltage at ISENSE above
1 V or pull the COMP terminal below a voltage two diode drops above ground. Either method causes the output
of the PWM comparator to be high (refer to block diagram). The PWM latch is reset dominant so that the output
remains low until the next clock cycle after the shutdown condition at the COMP or ISENSE terminal is removed.
In one example, an externally latched shutdown can be accomplished by adding an SCR that resets by cycling
VCC below the lower UVLO threshold. At this point, the reference turns off, allowing the SCR to reset.
1 kΩ
VREF
COMP
Shutdown
330 Ω
ISENSE
500 Ω
Shutdown
To Current-Sense
Resistor
Figure 5. Shutdown Techniques
A fraction of the oscillator ramp can be summed resistively with the current-sense signal to provide slope
compensation for converters requiring duty cycles over 50% (see Figure 6). Note that capacitor C forms a filter
with R2 to suppress the leading-edge switch spikes.
VREF
0.1 µF
RT
RT/CT
CT
R1
ISENSE
R2
ISENSE
C
RSENSE
Figure 6. Slope Compensation
Submit Documentation Feedback
13
PACKAGE OPTION ADDENDUM
www.ti.com
6-Dec-2006
PACKAGING INFORMATION
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
TL2842BD
ACTIVE
SOIC
D
14
50
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2842BDG4-8
ACTIVE
SOIC
D
8
75
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2842BDR
ACTIVE
SOIC
D
14
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2842BDRG4-8
ACTIVE
SOIC
D
8
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2842BP
ACTIVE
PDIP
P
8
50
Pb-Free
(RoHS)
CU NIPDAU
N / A for Pkg Type
TL2842BPE4
ACTIVE
PDIP
P
8
50
Pb-Free
(RoHS)
CU NIPDAU
N / A for Pkg Type
TL2843BD
ACTIVE
SOIC
D
14
50
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2843BD-8
ACTIVE
SOIC
D
8
75
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2843BDG4
ACTIVE
SOIC
D
14
50
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2843BDG4-8
ACTIVE
SOIC
D
8
75
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2843BDR
ACTIVE
SOIC
D
14
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2843BDR-8
ACTIVE
SOIC
D
8
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2843BDRG4
ACTIVE
SOIC
D
14
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2843BDRG4-8
ACTIVE
SOIC
D
8
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2843BP
ACTIVE
PDIP
P
8
CU NIPDAU
N / A for Pkg Type
TL2843BPG4
ACTIVE
PDIP
P
8
TL2844BD
ACTIVE
SOIC
D
TL2844BD-8
ACTIVE
SOIC
TL2844BDG4
ACTIVE
TL2844BDG4-8
Lead/Ball Finish
MSL Peak Temp (3)
50
Pb-Free
(RoHS)
TBD
Call TI
14
50
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
D
8
75
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
SOIC
D
14
50
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
ACTIVE
SOIC
D
8
75
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2844BDR
ACTIVE
SOIC
D
14
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2844BDR-8
ACTIVE
SOIC
D
8
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2844BDRG4
ACTIVE
SOIC
D
14
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2844BDRG4-8
ACTIVE
SOIC
D
8
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2844BP
ACTIVE
PDIP
P
8
CU NIPDAU
N / A for Pkg Type
50
Addendum-Page 1
Pb-Free
(RoHS)
Call TI
PACKAGE OPTION ADDENDUM
www.ti.com
6-Dec-2006
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
TL2844BPE4
ACTIVE
PDIP
P
8
50
Pb-Free
(RoHS)
CU NIPDAU
N / A for Pkg Type
TL2845BD
ACTIVE
SOIC
D
14
50
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2845BD-8
ACTIVE
SOIC
D
8
75
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2845BDG4
ACTIVE
SOIC
D
14
50
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2845BDR
ACTIVE
SOIC
D
14
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2845BDR-8
ACTIVE
SOIC
D
8
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2845BDRG4
ACTIVE
SOIC
D
14
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL2845BP
ACTIVE
PDIP
P
8
50
Pb-Free
(RoHS)
CU NIPDAU
N / A for Pkg Type
TL2845BPE4
ACTIVE
PDIP
P
8
50
Pb-Free
(RoHS)
CU NIPDAU
N / A for Pkg Type
TL3842BD
ACTIVE
SOIC
D
14
50
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3842BD-8
ACTIVE
SOIC
D
8
75
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3842BDG4-8
ACTIVE
SOIC
D
8
75
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3842BDR
ACTIVE
SOIC
D
14
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3842BDR-8
ACTIVE
SOIC
D
8
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3842BDRG4
ACTIVE
SOIC
D
14
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3842BDRG4-8
ACTIVE
SOIC
D
8
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3842BP
ACTIVE
PDIP
P
8
50
Pb-Free
(RoHS)
CU NIPDAU
N / A for Pkg Type
TL3842BPE4
ACTIVE
PDIP
P
8
50
Pb-Free
(RoHS)
CU NIPDAU
N / A for Pkg Type
TL3843BD
ACTIVE
SOIC
D
14
50
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3843BD-8
ACTIVE
SOIC
D
8
75
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3843BDG4
ACTIVE
SOIC
D
14
50
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3843BDG4-8
ACTIVE
SOIC
D
8
75
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3843BDR
ACTIVE
SOIC
D
14
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3843BDRG4
ACTIVE
SOIC
D
14
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3843BP
ACTIVE
PDIP
P
8
50
Pb-Free
(RoHS)
CU NIPDAU
N / A for Pkg Type
TL3843BPE4
ACTIVE
PDIP
P
8
50
Pb-Free
(RoHS)
CU NIPDAU
N / A for Pkg Type
Addendum-Page 2
Lead/Ball Finish
MSL Peak Temp (3)
PACKAGE OPTION ADDENDUM
www.ti.com
6-Dec-2006
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
TL3844BD
ACTIVE
SOIC
D
14
50
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3844BD-8
ACTIVE
SOIC
D
8
75
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3844BDG4
ACTIVE
SOIC
D
14
50
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3844BDG4-8
ACTIVE
SOIC
D
8
75
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3844BDR-8
ACTIVE
SOIC
D
8
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3844BDRG4
ACTIVE
SOIC
D
14
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3844BDRG4-8
ACTIVE
SOIC
D
8
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3844BP
ACTIVE
PDIP
P
8
50
Pb-Free
(RoHS)
CU NIPDAU
N / A for Pkg Type
TL3844BPE4
ACTIVE
PDIP
P
8
50
Pb-Free
(RoHS)
CU NIPDAU
N / A for Pkg Type
TL3845BD
ACTIVE
SOIC
D
14
50
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3845BD-8
ACTIVE
SOIC
D
8
75
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3845BDG4
ACTIVE
SOIC
D
14
50
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3845BDG4-8
ACTIVE
SOIC
D
8
75
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3845BDR
ACTIVE
SOIC
D
14
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3845BDR-8
ACTIVE
SOIC
D
8
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3845BDRG4
ACTIVE
SOIC
D
14
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3845BDRG4-8
ACTIVE
SOIC
D
8
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TL3845BP
ACTIVE
PDIP
P
8
50
Pb-Free
(RoHS)
CU NIPDAU
N / A for Pkg Type
TL3845BPE4
ACTIVE
PDIP
P
8
50
Pb-Free
(RoHS)
CU NIPDAU
N / A for Pkg Type
Lead/Ball Finish
MSL Peak Temp (3)
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in
a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check
http://www.ti.com/productcontent for the latest availability information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and
Addendum-Page 3
PACKAGE OPTION ADDENDUM
www.ti.com
6-Dec-2006
package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS
compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder
temperature.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is
provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the
accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take
reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on
incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited
information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI
to Customer on an annual basis.
Addendum-Page 4
MECHANICAL DATA
MPDI001A – JANUARY 1995 – REVISED JUNE 1999
P (R-PDIP-T8)
PLASTIC DUAL-IN-LINE
0.400 (10,60)
0.355 (9,02)
8
5
0.260 (6,60)
0.240 (6,10)
1
4
0.070 (1,78) MAX
0.325 (8,26)
0.300 (7,62)
0.020 (0,51) MIN
0.015 (0,38)
Gage Plane
0.200 (5,08) MAX
Seating Plane
0.010 (0,25) NOM
0.125 (3,18) MIN
0.100 (2,54)
0.021 (0,53)
0.015 (0,38)
0.430 (10,92)
MAX
0.010 (0,25) M
4040082/D 05/98
NOTES: A. All linear dimensions are in inches (millimeters).
B. This drawing is subject to change without notice.
C. Falls within JEDEC MS-001
For the latest package information, go to http://www.ti.com/sc/docs/package/pkg_info.htm
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