850kHz 1A Buck DC/DC Converter General Description
The AAT1152 SwitchReg is a step-down switching converter ideal for applications where high efficiency, small size, and low ripple are critical. Able to deliver 1A with internal power MOSFETs, the current mode controlled IC is internally compensated for simplified system design and low external parts count. The AAT1152 features a Power-OK (POK) function which monitors the output, alerting the system if the output voltage falls out of regulation. The AAT1152 is available in a Pb-free MSOP-8 package and is rated over the -40°C to +85°C temperature range.
AAT1152
Features
• • • • • • • • • • • • • • • •
SwitchReg™
5.5V Max Supply Input Fixed or Adjustable VOUT 1.0V to 4.2V 1A Output Current Integrated Low On Resistance Power Switches Up to 95% Efficiency Power-OK Signal Internally Compensated Current Mode Control High Initial Accuracy: ±1% 850kHz Switching Frequency Constant Pulse Width Modulation (PWM) Mode Low Output Ripple with Light Load Internal Soft Start Current Limit Protection Over-Temperature Protection MSOP-8 Package -40°C to +85°C Temperature Range
Applications
• • • • • Cable/DSL Modems Computer Peripherals High Efficiency Conversion from 5V or 3.3V Supply Network Cards Set-Top Boxes
Typical Application
INPUT
100k
10μF
VP
AAT1152
POK
FB 4.1μH LX
ENABLE 100Ω VCC SGND 0.1μF PGND 3 x 22μF OUTPUT
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850kHz 1A Buck DC/DC Converter Pin Descriptions
Pin #
1 2 3 4 5 6 7 8
AAT1152
Symbol
FB SGND EN VCC VP LX POK PGND
Function
Feedback input pin. Signal ground. Converter enable pin. Small signal filtered bias supply. Input supply for converter power stage. Inductor connection pin. Power-OK indicator. Open-drain output is low when VOUT falls out of regulation. Power ground return for output stage.
Pin Configuration
MSOP-8
FB SGND EN VCC
1
8
PGND POK LX VP
1
2
7
2
3
6
4
5
2
1152.2006.09.1.7
850kHz 1A Buck DC/DC Converter Absolute Maximum Ratings1
TA = 25°C, unless otherwise noted. Symbol
VCC, VP VLX VFB VEN, VPOK TJ TLEAD VESD
AAT1152
Description
VCC, VP to GND LX to GND FB to GND POK, EN to GND Operating Junction Temperature Range Maximum Soldering Temperature (at leads, 10 sec) ESD Rating2 - HBM
Value
6 -0.3 to VP + 0.3 -0.3 to VCC + 0.3 -0.3 to 6 -40 to 150 300 3000
Units
V V V V °C °C V
Thermal Characteristics3
Symbol
ΘJA PD
Description
Maximum Thermal Resistance (MSOP-8) Maximum Power Dissipation (MSOP-8)
Value
150 833
Units
°C/W mW
Recommended Operating Conditions
Symbol
T
Description
Ambient Temperature Range
Rating
-40 to +85
Units
°C
1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at conditions other than the operating conditions specified is not implied. Only one Absolute Maximum Rating should be applied at any one time. 2. Human body model is a 100pF capacitor discharged through a 1.5kΩ resistor into each pin. 3. Mounted on a demo board. 1152.2006.09.1.7
3
850kHz 1A Buck DC/DC Converter Electrical Characteristics
VIN = VCC = VP = 5V, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA = 25°C. Symbol
VIN VOUT ILIM IQ ΔVOUT (VOUT*ΔVIN) ΔVOUT/VOUT FOSC RDSON(H) RDSON(L) VEN(H) VEN(L) IEN VUVLO VUVLO(hys) TSD THYS ISHDN VTH(POK) RPOK
AAT1152
Description
Operation Voltage DC Output Voltage Tolerance Current Limit Quiescent Supply Current Load Regulation Line Regulation Oscillator Frequency High-Side Switch On Resistance Low-Side Switch On Resistance Enable Input High Voltage Enable Input Low Voltage Enable Pin Leakage Current Under-Voltage Lockout
Conditions
IOUT = 500mA TA = 25°C Full Temp
Min
2.7 -1.0 -2.0 1.2
Typ
Max
5.5 1.0 2.0
Units
V % A μA % %/V kHz mΩ mΩ V V μA V mV °C °C
TA = 25°C No Load, VFB = 0 VIN = 4.2V, ILOAD = 0 to 1A VIN = 2.7V to 5.5V TA = 25°C TA = 25°C TA = 25°C VIN = 2.7V to 5.5V VIN = 2.7V to 5.5V VEN = 5.5V VIN Rising VIN Falling
700
160 3 0.2 850 110 100
300
1000 150 150 0.6 1 2.5
1.4
1.2 250 140 15 1 90 88 4
Under-Voltage Lockout Hysteresis Over-Temperature Shutdown Threshold Over-Temperature Shutdown Hysteresis Shutdown Current VEN = 0, VIN = 5.5V VFB Ramping Up Power-OK Threshold VFB Ramping Down Power-OK Pull-Down On Resistance
μA % of VFB Ω
4
1152.2006.09.1.7
850kHz 1A Buck DC/DC Converter Typical Characteristics
Efficiency vs. Output Current
(VOUT = 1.5V)
100 80
170
AAT1152
High Side RDS(ON) vs. Temperature
2.7V
RDS(ON) (mΩ)
150
3.6V 2.7V
Efficiency (%)
60
130 110 90 70 -20
4.2V
40 20 0 10 100 1000
3.6V
4.2V
5.5V
0
20
40
60
80
100
120
Output Current (mA)
Temperature (°C)
Low Side RDS(ON) vs. Temperature
170 150 130 120
RDS(ON) vs. Input Voltage
RDS(ON) (mΩ)
RDS(ON) (mΩ)
High Side
110 100 90 80 2.5 3 3.5 4 4.5 5 5.5
130 110 90 70 -20
3.6V 2.7V 5.5V 4.2V
0 20 40 60 80 100 120
Low Side
Temperature (°C)
Input Voltage (V)
Enable Threshold vs. Input Voltage
1.2 3.5
Oscillator Frequency Variation vs. Supply Voltage
Enable Threshold (V)
1.1 1
Variation (%)
VEN(H)
2.5 1.5 0.5 -0.5 -1.5
0.9 0.8
VEN(L)
0.7 2.5 3 3.5 4 4.5 5 5.5
2.5
3
3.5
4
4.5
5
5.5
Input Voltage (V)
Supply Voltage (V)
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850kHz 1A Buck DC/DC Converter Typical Characteristics
Oscillator Frequency Variation vs. Temperature
(VIN = 3.6V)
10 6 1.0 0.6 0.2 -0.2 -0.6 -1.0 -20
AAT1152
Output Voltage vs. Temperature
(IOUT = 900mA; VOUT = 1.5V)
Output Voltage Error (%)
Variation (%)
2 -2 -6 -10 -20
VIN = 2.7V
VIN = 3.6V
0
20
40
60
80
100
0
20
40
60
80
100
Temperature (°C)
Temperature (°C)
Line Regulation
(VOUT = 1.5V)
0.25 0.15
0 -1
Load Regulation
(VOUT = 1.5V; VIN = 3.6V)
Accuracy (%)
IOUT = 1.0A
0.05 -0.05 -0.15 -0.25 2.5 3 3.5 4 4.5 5 5.5
Error (%)
-2 -3 -4 -5 0 150 300 450 600 750 900
IOUT = 0.4A
Input Voltage (V)
IOUT (mA)
Load Regulation
(VOUT = 3.3V; VIN = 5.0V)
0 -1 100
Efficiency vs. Input Voltage
(VOUT = 1.5V)
IO = 1A
90
VOUT Error (%)
Efficiency (%)
-2 -3 -4 -5 0 150 300 450 600 750 900 1050
80 70 60 50 2.5 3 3.5
IO = 0.4A
Output Current (A)
4
4.5
5
5.5
Input Voltage (V)
6
1152.2006.09.1.7
850kHz 1A Buck DC/DC Converter Typical Characteristics
(CO = 22μF; VO = 1.5V; VIN = 3.6V; IO = 1A)
20 16 12 8 200 160 80 40 0 120 12
AAT1152
AAT1152 Loop Gain and Phase
No Load Input Current vs. Temperature
(VCC = VP)
VCC = 5.5V
VCC = 5.0V
Input Current (mA)
Phase
10 8 6 4 2 0 -20 -5 10 25 40 55 70 85
Phase (degrees)
Gain (dB)
4 0 -4 -8 -12 -16 -20 10
Gain 4 x 22μF 5 x 22μF
100
3 x 22μF
-40 -80 -120 -160 -200 1000
VCC = 4.2V
VCC = 3.6V
VCC = 2.7V
Frequency (kHz)
Temperature (°C)
Non-Switching IQ vs. Temperature
(FB = 0V; VP = VCC)
Switching Waveform
(VIN = 3.6V; VOUT = 1.5V; IOUT = 1.2A)
Operating Current (μA)
200 190 180 170 160 150 140 130 120 110 100 -20
VCC = 5.5V VCC = 5.0V VCC = 4.2V VCC = 2.7V
-5 10 25
V(LX) 2V/div
VCC = 3.6V
IL 500mA/div
70 85
40
55
Temperature (°C)
Time (500ns/div)
Transient Response
(VIN = 3.6V; VOUT = 1.5V; ILOAD = 0.25 to 1.2A) VOUT 50mV/div
Output Ripple
(VIN = 3.6V; VOUT = 1.5V; IOUT = 0A)
VOUT 5mV/div BW = 20MHz
Inductor Current 500mA/div
LX 2V/div
Time (20µs/div)
Time (500ns/div)
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850kHz 1A Buck DC/DC Converter Typical Characteristics
Output Ripple
(VIN = 3.6V; VOUT = 1.5V; IOUT = 1A)
AAT1152
Output Ripple
(VIN = 5.0V; VOUT = 3.3V; IOUT = 0A)
VOUT 5mV/div BW = 20MHz
VOUT 5mV/div BW = 20MHz
LX 2V/div
LX 2V/div
Time (500ns/div)
Time (500ns/div)
Output Ripple
(VIN = 5.0V; VOUT = 3.3V; IOUT = 1A)
VOUT 5mV/div BW = 20MHz
LX 2V/div
Time (500ns/div)
8
1152.2006.09.1.7
850kHz 1A Buck DC/DC Converter Functional Block Diagram
VCC VP = 2.7V to 5.5V
AAT1152
1.0V REF
FB
OP. AMP
CMP
DH
LOGIC OSC
LX
DL Temp. Sensing Power Good
SGND
POK
EN
PGND
Applications Information
Control Loop
The AAT1152 is a peak current mode buck converter. The inner wide bandwidth loop controls the peak current of the output inductor. The output inductor current is sensed through the P-channel MOSFET (high side) and is also used for short-circuit and overload protection. A fixed slope compensation signal is added to the sensed current to maintain stability. The loop appears as a voltage-programmed current source in parallel with the output capacitor. The voltage error amplifier output programs the current loop for the necessary inductor current to force a constant output voltage for all load and line conditions. The feedback resistive divider is internal, dividing the output voltage to the error amplifier ref-
erence voltage of 1V. The error amplifier does not have the large DC gain typical of most error amplifiers. This eliminates the need for external compensation components, while still providing sufficient DC loop gain for load regulation. The crossover frequency and phase margin are set by the output capacitor value only.
Soft Start/Enable
Soft start increases the inductor current limit point in discrete steps when the input voltage or enable input is applied. It limits the current surge seen at the input and eliminates output voltage overshoot (see Figure 1). When pulled low, the enable input forces the AAT1152 into a low-power, non-switching state. The total input current during shutdown is less than 1μA.
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850kHz 1A Buck DC/DC Converter
AAT1152
Enable 2V/div
VOUT 1V/div IL 0.5A/div
Time (200μs/div)
Figure 1: Inrush Limit (VIN = 3.6V; VOUT = 1.5V; IL = 1A).
Current Limit and Over-Temperature Protection
For overload conditions, the peak input current is limited. Figure 2 displays the current limit characteristics. As load impedance decreases and the output voltage falls closer to zero, more power is dissipated internally, raising the device temperature. Thermal protection completely disables switching when internal dissipation becomes excessive, protecting the device from damage. The junction over-temperature threshold is 140°C with 15°C of hysteresis.
Power and Signal Source
Separate small signal ground and power supply pins isolate the internal control circuitry from the noise associated with the output MOSFET switching. The low pass filter R1 and C3 (shown in schematic Figures 3 and 4) filters the noise associated with power switching.
3.5
Output Voltage (V)
3 2.5 2 1.5 1 0.5 0 0
VCC = VP = 5.0V VO = 3.3V
VCC = VP = 3.6V VO = 1.5V
0.5
1
1.5
2
2.5
Output Current (A)
Figure 2: Current Limit Characteristics.
10
1152.2006.09.1.7
850kHz 1A Buck DC/DC Converter
R5 100k U1 AAT1152-1.0 R1 100 R2 C1 10μF 100k C2 0.1μF EN VP VCC EN FB POK LX LX R4 10k 1% L1 2.7μH C3, C4, C5 3x 22μF 6.3V
AAT1152
POK
VIN+ 3.3V
R3 2.55k 1%
VO+ 1.25V 1A
SGND PGND
VC1 Murata 10μF 6.3V X5R GRM42-6X 5R106K6.3 C3, C4, C5 MuRata 22μF 6.3V GRM21BR60J226ME39L X5R 0805 L1 Sumida CDRH4D28-2R 7μH
Figure 3: 3.3V to 1.25V Converter.
Efficiency vs. Output Current
R5 100k U1 AAT1152-1.5 VP EN VCC EN FB POK LX LX C3, C4, C5 3x 22μF 6.3V L1 4.1μH POK
100
(VOUT = 1.5V)
VIN + 2.7V - 5.5V R1 100 R2 C1 10μF 100k C2 0.1μF
V O+ 1.5V 1A
80
2.7V
Efficiency (%)
60
4.2V
40 20 0 10 100 1000
SGND PGND
3.6V
VC1 Murata 10μF 6.3V X5R GRM42-6X5R106K6.3 C3, C4, C5 MuRata 22μF 6.3V GRM21BR60J226ME39L X5R 0805 L1 Sumida CDRH5D 18-4R 1μH
Output Current (mA)
Figure 4: Lithium-Ion to 1.5V Output Converter.
Power Good
The AAT1152 features an integrated POK comparator and open-drain output signal. The POK pin goes low when the converter output is 12% or more below its nominal regulation voltage or when the device is in shutdown. Connect a pull-up resistor from POK to the converter input or output. Typical resistor pull-up values range from 100k to 10k.
Inductor
The output inductor is selected to limit the ripple current to some predetermined value, typically 20% to 40% of the full load current at the maximum input
voltage. Manufacturer's specifications list both the inductor DC current rating, which is a thermal limitation, and the peak current rating, which is determined by the saturation characteristics. The inductor should not show any appreciable saturation under normal load conditions. During overload and short-circuit conditions, the average current in the inductor can meet or exceed the ILIMIT point of the AAT1152 without affecting converter performance. Some inductors may have sufficient peak and average current ratings yet result in excessive losses due to a high DCR. Always consider the losses associated with the DCR and its effect on the total converter efficiency when selecting an inductor.
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850kHz 1A Buck DC/DC Converter
For a 1A load and the ripple set to 30% at the maximum input voltage, the maximum peak-to-peak ripple current is 300mA. The inductance value required is 3.9μH.
⎛V⎞ VOUT ⋅ 1 - OUT IO ⋅ k ⋅ FS ⎝ VIN ⎠ 1.5V ⎛ 1.5V ⎞ ⋅11.0A ⋅ 0.3 ⋅ 830kHz ⎝ 4.2V⎠
AAT1152
Input Capacitor
The primary function of the input capacitor is to provide a low impedance loop for the edges of pulsed current drawn by the AAT1152. A low ESR/ESL ceramic capacitor is ideal for this function. To minimize the stray inductance, the capacitor should be placed as closely as possible to the IC. This keeps the high frequency content of the input current localized, minimizing radiated and conducted EMI while facilitating optimum performance of the AAT1152. Ceramic X5R or X7R capacitors are ideal for this function. The size required will vary depending on the load, output voltage, and input voltage source impedance characteristics. A typical value is around 10μF. The input capacitor RMS current varies with the input voltage and output voltage. The equation for the RMS current in the input capacitor is:
L= L=
L = 3.9μH
The factor "k" is the fraction of full load selected for the ripple current at the maximum input voltage. The corresponding inductor RMS current is:
⎛ ΔI 2 ⎞ IRMS = ⎜ IO2 + ≈ IO = 1A 12 ⎟ ⎝ ⎠
ΔI is the peak-to-peak ripple current which is fixed by the inductor selection above. For a peak-to-peak current of 30% of the full load current, the peak current at full load will be 115% of the full load. The 4.1μH inductor selected from the Sumida CDRH5D18 series has a 57mΩ DCR and a 1.95A DC current rating. At full load, the inductor DC loss is 57mW, which amounts to a 3.8% loss in efficiency.
IRMS = IO ⋅
VO ⎛ VO ⎞ ⋅ 1VIN ⎠ VIN ⎝
The input capacitor RMS ripple current reaches a maximum when VIN is two times the output voltage where it is approximately one half of the load current. Losses associated with the input ceramic capacitor are typically minimal and are not an issue. Proper placement of the input capacitor can be seen in the reference design layout in Figures 5 and 6.
Figure 5: AAT1152 Evaluation Board Layout Top Layer. 12
Figure 6: AAT1152 Evaluation Board Layout Bottom Layer.
1152.2006.09.1.7
850kHz 1A Buck DC/DC Converter
Output Capacitor
Since there are no external compensation components, the output capacitor has a strong effect on loop stability. Larger output capacitance will reduce the crossover frequency with greater phase margin. For the 1.5V 1A design using the 4.1μH inductor, three 22μF 6.3V X5R capacitors provide a stable output. In addition to assisting stability, the output capacitor limits the output ripple and provides holdup during large load transitions. The output capacitor RMS ripple current is given by:
1 2⋅ 3 VOUT ⋅ (VIN - VOUT) L ⋅ FS ⋅ VIN
AAT1152
Layout Considerations
Figures 5 and 6 display the suggested PCB layout for the AAT1152. The most critical aspect of the layout is the placement of the input capacitor C1. For proper operation, C1 must be placed as closely as possible to the AAT1152.
Thermal Calculations
There are two types of losses associated with the AAT1152 output switching MOSFET: switching losses and conduction losses. Conduction losses are associated with the RDS(ON) characteristics of the output switching device. At full load, assuming continuous conduction mode (CCM), a simplified form of the total losses is:
IRMS =
⋅
For a ceramic capacitor, dissipation due to the RMS current of the capacitor is not a concern. Tantalum capacitors with sufficiently low ESR to meet output voltage ripple requirements also have an RMS current rating much greater than that actually seen in this application.
PLOSS =
IO2 ⋅ (RDS(ON)H ⋅ VO + RDS(ON)L ⋅ (VIN - VO)) VIN
+ tsw ⋅ FS ⋅ IO ⋅ VIN + IQ ⋅ VIN
Adjustable Output
For applications requiring an output other than the fixed outputs available, the 1V version can be externally programmed. Resistors R3 and R4 of Figure 3 force the output to regulate higher than 1V. R4 should be 100 times less than the internal 1MΩ resistance of the FB pin. Once R4 is selected, R3 can be calculated. For a 1.25V output with R4 set to 10.0kΩ, R3 is 2.55kΩ.
Once the total losses have been determined, the junction temperature can be derived from the ΘJA for the MSOP-8 package.
R3 = (VO - 1) ⋅ R4 = 0.25 ⋅ 10.0kΩ = 2.55kΩ
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850kHz 1A Buck DC/DC Converter
Design Example:
Specifications IOUT IRIPPLE VOUT VIN Fs 1A 30% of full load at max VIN 1.5V 2.7V to 4.2V (3.6V nominal) 830kHz
AAT1152
Maximum Input Capacitor Ripple:
IRMS = IO ⋅ VO ⎛ VO ⎞ IO ⋅ 1= = 0.5ARMS, VIN = 2 ⋅ VO VIN ⎝ VIN⎠ 2
P = ESRCOUT ⋅ IRMS2 = 5mΩ ⋅ 0.52A = 1.25mW
Inductor Selection:
L=
⎛V⎞ VOUT 1.5V ⎛ 1.5V⎞ ⋅ 1 - OUT = ⋅ 1= 3.9μH IO ⋅ k ⋅ FS ⎝ VIN ⎠ 1A ⋅ 0.3 ⋅ 830kHz ⎝ 4.2V⎠
Select Sumida Inductor CDRH5D18 4.1μH 57mΩ 2.0mm height.
ΔI =
⎛ 1.5V ⎞ VO ⎛ V⎞ 1.5V ⋅ 1- O = ⋅ 1= 280mA VIN ⎠ 4.1μH ⋅ 830kHz ⎝ 4.2V⎠ L ⋅ FS ⎝
IPK = IOUT +
ΔI = 1A + 0.14A = 1.14A 2
P = IO2 ⋅ DCR = 57mW
Output Capacitor Dissipation:
IRMS = VOUT ⋅ (VIN - VOUT) 1.5V ⋅ (4.2V - 1.5V) 1 1 ⋅ ⋅ = = 82mARMS L ⋅ FS ⋅ VIN 2⋅ 3 2 ⋅ 3 4.1μH ⋅ 830kHz ⋅ 4.2V
PESR = ESRCOUT ⋅ IRMS2 = 5mΩ ⋅ 0.0822A = 33μW
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850kHz 1A Buck DC/DC Converter
AAT1152 Dissipation:
P= IO2 • (RDS(ON)H • VO + RDS(ON)L • (VIN -VO)) VIN + (tsw • FS • IO + IQ) • VIN
AAT1152
=
(0.14Ω • 1.5V + 0.145Ω • (3.6V - 1.5V)) 3.6V
+ (20ns • 830kHz • 1.0A + 0.3mA) • 3.6V = 0.203W
TJ(MAX) = TAMB + ΘJA • PLOSS = 85°C + 150°C/W • 0.203W = 115°C
Manufacturer
TaiyoYuden Toko Sumida Sumida MuRata MuRata
Part Number
NPO5DB4R7M A914BYW-3R5M-D52LC CDRH5D28-4R2 CDRH5D18-4R1 LQH55DN4R7M03 LQH66SN4R7M03
Value
4.7μH 3.5μH 4.2μH 4.1μH 4.7μH 4.7μH
Max DC Current
1.4A 1.34A 2.2A 1.95A 2.7A 2.2A
DCR
0.038 0.073 0.031 0.057 0.041 0.025
Size (mm) L×W×H Type 5.9 × 6.1 × 2.8 Shielded 5.0 × 5.0 × 2.0 Shielded 5.7 × 5.7 × 3.0 Shielded 5.7 × 5.7 × 2.0 Shielded 5.0 × 5.0 × 4.7 Non-Shielded 6.3 × 6.3 × 4.7 Shielded
Table 1: Surface Mount Inductors.
Manufacturer
MuRata MuRata MuRata MuRata
Part Number
GRM40 X5R 106K 6.3 GRM42-6 X5R 106K 6.3 GRM21BR60J226ME39L GRM21BR60J106ME39L
Value
10μF 10μF 22μF 10μF
Voltage
6.3V 6.3V 6.3V 6.3V
Temp. Co.
X5R X5R X5R X5R
Case
0805 1206 0805 0805
Table 2: Surface Mount Capacitors.
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850kHz 1A Buck DC/DC Converter Ordering Information
Output Voltage1
1.0V (Adj. VOUT ≥ 1.0V) 1.8V 2.5V 3.3V
AAT1152
Package
MSOP-8 MSOP-8 MSOP-8 MSOP-8
Marking2
LTXYY MLXYY MMXYY IAXYY
Part Number (Tape and Reel)3
AAT1152IKS-1.0-T1 AAT1152IKS-1.8-T1 AAT1152IKS-2.5-T1 AAT1152IKS-3.3-T1
All AnalogicTech products are offered in Pb-free packaging. The term “Pb-free” means semiconductor products that are in compliance with current RoHS standards, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. For more information, please visit our website at http://www.analogictech.com/pbfree.
Package Information
MSOP-8
4° ± 4° 1.95 BSC
3.00 ± 0.10
4.90 ± 0.10
0.60 ± 0.20 PIN 1 0.254 BSC
0.95 REF
3.00 ± 0.10 10° ± 5°
0.95 ± 0.15 0.85 ± 0.10
0.075 ± 0.075 0.65 BSC 0.30 ± 0.08
All dimensions in millimeters.
1. Contact Sales for other voltage options. 2. XYY = assembly and date code. 3. Sample stock is generally held on part numbers listed in BOLD.
16
GAUGE PLANE
0.155 ± 0.075
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850kHz 1A Buck DC/DC Converter
AAT1152
© Advanced Analogic Technologies, Inc. AnalogicTech cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in an AnalogicTech product. No circuit patent licenses, copyrights, mask work rights, or other intellectual property rights are implied. AnalogicTech reserves the right to make changes to their products or specifications or to discontinue any product or service without notice. Customers are advised to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and conditions of sale supplied at the time of order acknowledgement, including those pertaining to warranty, patent infringement, and limitation of liability. AnalogicTech warrants performance of its semiconductor products to the specifications applicable at the time of sale in accordance with AnalogicTech’s standard warranty. Testing and other quality control techniques are utilized to the extent AnalogicTech deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily performed. AnalogicTech and the AnalogicTech logo are trademarks of Advanced Analogic Technologies Incorporated. All other brand and product names appearing in this document are registered trademarks or trademarks of their respective holders.
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