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MIC3838/3839
Micrel
MIC3838/3839
Flexible Push-Pull PWM Controller
General Description
The MIC3838 and MIC3839 are a family of complementary output push-pull PWM control ICs that feature high speed and low power consumption. The MIC3838/9 are ideal for telecom level (36V to 75V) isolated step down dc/dc conversion applications where high output current, small size, and high efficiency are required The MIC3838/9 are designed for high flexibility with minimum pin-count. The devices are easily configurable for either voltage-mode or current-mode control. Additionally, the MIC3838/9 can easily implement a volt-second clamp that automatically limits the duty cycle during input transients, allowing designers to use the smallest possible transformers and power components. A 3V reference output is also available that eliminates the need for an external reference. The dual-ended push-pull architecture of the MIC3838/9 allows more efficient utilization of the transformer than singleended topologies, allowing smaller size dc/dc solutions. Additionally, the out-of-phase push-pull topology allows a higher effective duty cycle, reducing input and output ripple as well as stress on the external components. The dead-time between the two outputs is adjustable between 60ns to 200ns, limiting the duty cycle of each output stage to less than 50%. The MIC3838 has a turn-on threshold of 12.5V whereas the MIC3839 has a lower turn-on threshold of 4.3V. Both devices are available in a small size MSOP-10 package with an operating range of -40C to +85C. Data sheets and support documentation can be found on Micrel's web site at www.micrel.com.
Features
Dual output drive stages in push-pull configuration Configurable for current-mode or voltage-mode control Easily implements volt-second clamp Leading edge current-sense blanking 3V reference output available 130A typical start-up current 1mA typical run current Operation to 1MHz On-chip error amplifier with 4MHz gain bandwidth product * Internal soft start * On-chip VDD clamping * Output drive stages capable of 500mA peak source current, 1A peak sink current * * * * * * * * *
Applications
* High efficiency "brick" power supply modules * Half bridge converters * Full bridge converters * Push-pull converters * Voltage-fed push-pull converters * Telecom equipment and power supplies * Industrial power supplies * 42V automotive power supplies * Base stations * Networking power supplies
Typical Application
VIN 36V to 75V Start-Up Circuitry VOUT 12V 100W
MIC3838x-x
VREF RC GND
VDD
OUTB
COMP RAMP FB ILIM
Driver
Feed Forward Ramp/ Volt Sec Clamp Reference & Isolation
OUTA
Voltage-Mode Half-Bridge Converter CIrcuit
Micrel, Inc. * 1849 Fortune Drive * San Jose, CA 95131 * USA * tel + 1 (408) 944-0800 * fax + 1 (408) 944-0970 * http://www.micrel.com
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MIC3838/3839
MIC3838/3839
Micrel
Ordering Information
Part Number MIC3838BMM MIC3839BMM Turn On Threshold 12.5V 4.3V Turn Off Threshold 8.3V 4.1V Temperature Range -40C to +85C -40C to +85C Package MSOP-10 MSOP-10
Pin Configuration
COMP 1 FB 2 ILIM 3 RAMP 4 RC 5 10 VREF 9 VDD 8 OUTA 7 OUTB 6 GND
MSOP-10 (MM)
Pin Description
Pin Number 1 Pin Name COMP Pin Function COMP is the output of the error amplifier and the input of the PWM comparator. The error amplifier in the MIC3838 is a true low-output impedance, 4MHz operational amplifier. As such, the COMP pin can both source and sink current. However, the error amplifier is internally current limited, so that zero duty cycle can be externally forced by pulling COMP to GND. The MIC3838 family features built-in full cycle soft start. Soft start is implemented as a clamp on the maximum COMP voltage. The inverting input to the error amplifier. The input to the peak current, and overcurrent comparators. The overcurrent comparator is only intended for fault sensing. Exceeding the overcurrent threshold will cause a soft start cycle. An internal MOSFET discharges the current sense filter capacitor to improve dynamic performance of the power converter. Input to the PWM comparator. Sawtooth ramp for PWM control. Allows for either current-mode or voltage-mode control. An internal MOSFET discharges the current sense filter capacitor. The oscillator programming pin. Only two components are required to program the oscillator, a resistor (tied between VDD and RC), and a capacitor (tied between RC and GND). The approximate oscillator frequency is determined by the simple formula:
2 3
FB ILIM
4
RAMP
5
RC
FOSCILLATOR =
1.41 RxC
The recommended range of timing resistors is between 7k and 200k and range of timing capacitors is between 100pF and 1000pF. Timing resistors less than 7k should be avoided. For best performance, keep the leads between components as short as possible. Separate ground and VDD traces to the external timing network are encouraged. 6 GND Ground. Return path for signal and gate drive functions.
MIC3838/3839
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MIC3838/3839
Micrel
Pin Description
Pin Number 7, 8 Pin Name OUTB, OUTA Pin Function Alternating high current output stages. Both stages are capable of driving the gate of a power MOSFET. Each stage is capable of 500mA peak source current, and 1A peak sink current. The output stages switch at half the oscillator frequency, in a push/pull configuration. When the voltage on the RC pin is rising, one of the two outputs is high, but during fall time, both outputs are off. This "dead time" between the two outputs, along with a slower output rise time than fall time, insures that the two outputs can not be on at the same time. This dead time is typically 60ns to 200ns and depends upon the values of the timing capacitor and resistor. The high-current output drivers consist of MOSFET output devices, which switch from VDD to GND. Each output stage also provides a very low impedance to overshoot and undershoot. This means that in many cases, external Schottky clamp diodes are not required. The power input connection for this device. Total VDD current is the sum of quiescent VDD current and the average gate drive (OUT) current. Knowing the operating frequency and the MOSFET gate charge (Qg), average OUT current can be calculated from IOUT = Qg * F, where Qg is the total gate change of all MOSFETs (OUTA and OUTB) and F is oscillator switching frequency. To prevent noise problems, bypass VDD to GND with a ceramic capacitor as close to the chip as possible. A 1F decoupling capacitor is recommended. Internal 3V supply. Will source 1mA maximum.
9
VDD
10
VREF
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MIC3838/3839
MIC3838/3839
Micrel
Absolute Maximum Rating (Note 1)
Supply Voltage (IDD 10mA) ...................................... +15V Supply Current ........................................................... 20mA OUTA/OUTB Source Current (peak) ...................... -0.5A OUTA/OUTB Sink Current (peak) ............................ 1.0A COMP Pin .................................................................... VDD Analog Inputs (FB, ILIM, RAMP) ......... -0.3V to VDD +0.3V NOT TO EXCEED 6V Junction Temperature .............................. -55C to +150C Storage Temperature (TS) ....................... -65C to +150C Lead Temperature (soldering, 10 sec.) ................... +300C ESD Rating, Note 3 ...................................................... 2kV
Operating Ratings (Note 2)
VDD Input Voltage (VDD) .......................................... Note 4 Oscillator Frequency (fOSC) ....................... 10kHz to 1MHz Ambient Temperature (TA) ......................... -40C to +85C Package Thermal Resistance MSOP-10 (JA) .................................................. 115C/W
Electrical Characteristics (Note 5)
TA = TJ = -40C to +85C, VDD=10V, Note 10,1F capacitor from VDD to GND, R=22k, C=330pF. Parameter Internal Reference Section Output voltage Line Regulation Load Regulation Oscillator Section Oscillator Frequency Oscillator Amplitude/VDD Error Amp Section Input Voltage Input Bias Current Open Loop Voltage Gain COMP Sink Current COMP Source Current COMP PM Clamp Voltage PWM Section Maximum Duty Cycle Minimum Duty Cycle Current Sense Section Gain ILIM Maximum Input Signal ILIM to Output Delay Ramp or ILIM Source Current Ramp or ILIM Sink Current ILIM Over Current Threshold COMP to Ramp Offset Output Section OUT Low Level OUT High Level Rise Time Fall Time I = 100mA I = -50mA, VDD - OUT CL = 1nF CL = 1nF 0.5 0.5 25 25 1 1 60 60 V V ns ns Ramp = ILIM = 0V Ramp = ILIM = 0.5V, RC = 5.5V Note 10 Guaranteed by design, Note 8 Note 9 COMP = 3V, ILIM from 0mV to 600mV -200 5 0.7 0.35 10 0.75 0.8 0.8 1.2 1.9 0.45 2.2 0.5 70 2.5 0.55 200 V/V V ns nA mA V V Measured at OUTA or OUTB COMP = 0V 48 49 50 0 % % (Guaranteed by design) FB = 2.2V, COMP = 1V FB = 1.3V, COMP = 3V, Note 7 VFB = 0V COMP = 2V 1.95 -1 60 0.3 -0.15 3.1 80 2.5 -0.5 3.6 4.0 2 2.05 1 V A dB mA mA V Note 6 180 0.44 200 0.5 220 0.56 kHz V/VDD IOUT = 0mA MIC3838 9V VDD 12V MIC3839 5V VDD 12V IOUT = 1mA 2.85 3.0 2 14 3.15 10 30 V mV mV Condition Min Typ Max Units
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MIC3838/3839
Parameter Undervoltage Lockout Section Start Threshold MIC3838, Note 11 MIC3839 Minimum Operating Voltage After Start Hysteresis MIC3838 MIC3839 MIC3838 MIC3839 Soft Start Section COMP Rise Time Overall Section Startup Current Operating Supply Current VDD Zener Shunt Voltage
Note 1. Note 2. Note 3. Note 4. Note 5. Note 6. Note 7.
Micrel
Condition Min Typ Max Units
11.5 4.1 7.6 3.9 3.5 0.1
12.5 4.3 8.3 4.1 4.2 0.2
13.5 4.5 9 4.3 5.1 0.3
V V V V V V
FB = 1.8V, Rise from 0.5V to 3V
2.5
20
ms A mA V
VDD < Start Threshold (MIC3839) FB = 0V, Ramp = ILIM = 0V, Notes 11, 12 IDD = 10mA, Note 13 13
130 1.5 14
260 2 15
Exceeding the absolute maximum rating may damage the device. The device is not guaranteed to function outside its operating rating. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF. Maximum operating voltage is equal to the VDD (zener) shunt voltage. When operating at or near the shunt voltage, care must be taken to limit the VDD pin current less than the 20mA VDD maximum current rating. Specification for packaged product only. Measured at RC. COMP pin is internally clamped to 3.65V(typ.). COMP pin source current is measured at VCOMP = 3.0V to avoid interferring with clamp. Minimum source current is higher as VCOMP approaches VCLAMP. Gain is defined by A =
Note 8. Note 9.
VCOMP
VCS , 0 VCS 0.4V.
Parameter measured at trip point of latch with FB at 0V
Note 10. The internal current sink on the Ramp and ILIM pin are designed to discharge an external filter capacitor. It is not intended to be a DC sink path. Internal discharge FET should be able to discharge the Volt-Sec clamp and feed-forward circuits in the figure below within 50ns. Note 11. For MIC3838, set VDD above the start threshold before setting at 10V. Note 12. Does not include current in the external oscillator network. Note 13. Start threshold and Zener Shunt threshold track one another.
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MIC3838/3839
MIC3838/3839
Micrel
Typical Characteristics
MIC3838 IDD Current MIC3839 IDD Current
16.0 14.0
IDD CURRENT (mA) IDD CURRENT (mA)
20
40
60
-40
-20
80
0
100
120 120 100
TEMPERATURE (C)
1.400
MIC3839 IDD Current vs. Temperature
1M
Oscillator Frequency vs. RC Values
C = 100pF
FREQUENCY (kHz)
RC Pin Capacitance vs. Deadtime
200 175
DEADTIME (ns)
VDD = 10V
IDD CURRENT (mA)
1.300
VIN = 10V
1.200
100k
C = 220pF C = 270pF C = 330pF C = 470pF C = 680pF
150 125 100 75
1.100
VIN = 5V
TEMPERATURE (C)
50k 100k 150k RESISTANCE (k)
200k
CAPACITANCE (pF)
RC Pin Resistance vs. Deadtime
89
FREQUENCY VARIATION (%)
1.50 1.00 0.50 0.00 -0.50 -1.00
MIC3838 Oscillator Variation vs. Temperature
FREQUENCY VARIATION (%)
2.000 1.500 1.000 0.500 0.000 -0.500 -1.000
MIC3839 % Oscillator Variation vs. Temperature
VIN = 5V
88
DEADTIME (ns)
VIN = 10V
87 86 85 84
VIN = 10V
0 20 40 60 80 100 120 140
160 180 200
-40
-20
-40
-20
20
40
60
80
20
40
60
100
120
140
80
0
0
100
RESISTANCE (k)
TEMPERATURE (C)
TEMPERATURE (C)
0.4 0.3
MIC3839 Oscillator Variation vs. VDD
2.04 2.02 2.00
VREF (V)
MIC3839 Error Amplifier Reference vs. VDD
2.040 2.030
VREF (V)
MIC3838 Error Amplifier Reference vs. Temperature
0.35
OSCILLATOR (%)
0.25 0.2 0.15 0.1 0.05 0 -0.05 -0.1 0 OPERATING
2.020 2.010 2.000 1.990
VIN = 10V
1.98 1.96 1.94
-40
-20
20
40
60
80
120
2
4
6 8 10 VDD (V)
12
14
6
8
10 12 14 VDD (V)
16
18
TEMPERATURE (C)
MIC3838/3839
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August 2003
140
1.92 4
0
140
83
-1.500
1000
0
100
200
300
400
500
600
700
800
100
120
140
900
20
40
60
-40
-20
80
0
1.000
10k 0
C = 1000pF
50
140
10.0 9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0
1.260
MIC3838 IDD Current vs. Temperature
IDD CURRENT (mA)
12.0 10.0 8.0 6.0 4.0 2.0
1.250
1.240 VIN = 10V
1.230
0
2
4
6 8 10 12 14 VDD (V)
0
0
2
4
6 8 10 12 14 VDD (V)
1.220
MIC3838/3839
Micrel
2.040
MIC3839 Error Amplifier Reference vs. Temperature VIN = 5V
VTHRESHOLD (V)
0.56 0.55 0.54 0.53 0.52 0.51
MIC3838 Current Limit Threshold vs. VDD
0.540
MIC3839 Peak Current Limit vs. VDD
2.020
VIN = 10V
VTHRESHOLD (V)
2.030
VREF (V)
0.535
0.530
2.010
0.525
20
40
60
-40
-20
80
0
100
120
140
2.000
0.5 8
9
TEMPERATURE (C)
10 11 12 13 14 15 16 VDD (V)
0.520
0
2
4
6 8 10 12 14 VDD (V)
0.545 0.540 VTHRESHOLD (V) 0.535 0.530 0.525 0.520
MIC3838 Peak Current Limit vs. Temperature
MIC3839 Peak Current Limit vs. Temperature
0.550 0.545 0.540 0.535 VIN = 10V 0.530 VIN = 5V 0.525 0.520 0.515 0.510 0.505 0.500 -40 -20 0 20 40 60 80 100120140 TEMPERATURE (C) 3.020 3.010 3.000
VREF (V)
MIC3839 3V Reference Voltage vs. VDD
VIN = 10V
VTHRESHOLD (V)
2.990 2.980 2.970 2.960 4 5 6 7 8 9 10 11 12 13 14 VDD (V)
0.515 -40 -20 0 20 40 60 80 100120140 TEMPERATURE (C)
3.020 3.010 3.000
MIC3838 3V Reference vs. Temperature
2.990 2.980 2.970 2.960
40 20 0 -20
1E+0 1E+1 1E+2 1E+3 1E+4 1E+5 1E+6
90
45
FREQUENCY (Hz)
3.02 3.01 3.00
MIC3839 3V Reference Voltage vs. Current
VREF (V)
VDD = 4.3V 2.99 2.98 2.97 2.96 0 0.5 1.0 1.5 REFERENCE CURRENT (mA) VDD = 10.0V
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MIC3838/3839
1E+7
2.950 -40 -20 0 20 40 60 80 100120140 TEMPERATURE (C)
-40
0
PHASE ()
GAIN (dB)
VREF (V)
VREF (V)
VIN = 10V
3.060 3.050 3.040 3.030 VIN = 5V 3.020 3.010 3.000 2.990 VIN = 10V 2.980 2.970 2.960 2.950 -40 -20 0 20 40 60 80 100120140 TEMPERATURE (C)
MIC3839 3V Reference vs. Temperature
120 100 80 60
MIC3838 Error Amplifier Phase-Gain vs. Frequency
180
135
MIC3838/3839
Micrel
Functional Diagram
FB
COMP
RAMP
ILIM
VDD Overcurrent Comparator 0.75V 2.0V 2.2V Error Amplifier OUTA VDD OK Oscillator 3.65V Peak Current Comparator 14V
0.5V
S Q R 1.2R VDD 1V S S Q R R Q T /Q 0.8V PWM Comparator PWM Latch Q
0.5V
VDD
R Soft Start OUTB
VREF
Voltage Reference Slope = 1V/ms
GND
RC
Figure 1. MIC3838 Block Diagram
VIN = 36V to 75V MIC3838
150k 13k
50k 4.5k
VCOMP
PWM Comparator
330pF
0.5V
Peak Current Comparator
330pF 0.75V Over Current Comparator
VMAX at Ramp Input = 1.5V VMAX at ILIM Input = 0.5V
Oscillator
Figure 2. Volt Second Clamp and Voltage Feed Forward Circuit
Functional Description
The MIC3838/9 is a high-speed power supply controller with push-pull output drive capability. MIC3838 has a higher VDD turn-on threshold and more hysteresis between VDD turn-on and turn-off than the MIC3839. The outputs of the controller operate in a push-pull fashion with a guaranteed dead time between them. A block diagram of the MIC3838/9 controller is shown in Figure 1.
VDD and Turn-on Sequence The oscillator and output gate drive signals are disabled when VDD is lower than the turn on threshold. Circuitry in the output drivers eliminates glitching or random pulsing during the start-up sequence. The oscillator is enabled when VDD is applied and reaches the turn-on threshold. The VDD comparator also turns off the internal soft-start discharge FET, slowly bringing up the COMP pin voltage. The VDD pin is internally clamped. As VDD approaches this clamp voltage, the VDD current will increase over the normal current draw of the IC. IDD currents greater than 20mA may cause excessive power dissipation in the MIC3838/9. 8 August 2003
MIC3838/3839
MIC3838/3839
Soft Start The soft start feature helps reduce surge currents at the power supply input source. An internal current source and capacitor ramp up from 0V to near VDD at a typical rate of 1V/ms. The soft start feature limits the output voltage of the error amplifier at the COMP pin. As the soft start voltage rises, it allows the COMP pin voltage to rise, which in turn allows the duty cycle of the output drivers to increase. The internal soft start voltage is discharged and remains discharged during the following conditions: 1. The VDD voltage drops below the turn-off threshold. 2. The voltage on the CS pin exceeds the overcurrent comparator threshold. Once the internal soft start discharge FET is turned on, it cannot be turned off until the internal soft start voltage drops down below 0.5V. This insures a clean restart. Oscillator The oscillator operates at twice the switching frequency of either OUTA or OUTB. The oscillator generates a sawtooth waveform on the RC pin. The rising edge of the waveform is controlled by the external resistor/capacitor combination. The fall time is set by the on-resistance of the discharge FET (see Figure 3). The fall time sets the delay (dead time) between the turn-off of one output driver and the turn-on of the other driver. A toggle flip-flop insures that drive signals to OUTA and OUTB are alternated and therefore insures a maximum duty cycle of less than 50% for each output driver. Graphs of component values vs. oscillator frequency and dead time are shown in the typical characteristic section of this specification.
VDD
Micrel
Graphs of oscillator frequency and dead time vs component values are shown in the Typical Characteristic section of this specification. The recommended range of timing resistors and capacitors is 7k to 200k and 100pF to 1000pF. To minimize oscillator noise and insure a stable waveform the following layout rules should be followed: 1. The higher impedance of capacitor values less than 100pF may causes the oscillator circuit to become more susceptible to noise. Parasitic pin and etch trace capacitances become a larger part of the total RC capacitance and may influence the desired switching frequency. 2. The circuit board etch between the timing resistor, capacitor, RC pin and ground must be kept as short as possible to minimize noise pickup and insure a stable oscillator waveform. 3. The ground lead of the capacitor must be routed close to the ground lead of the MIC3838/9. Current Sensing and Overcurrent Protection The features are: * Peak current limit * Overcurrent limit * Internal current sense discharge * Front edge blanking In current mode control, a PWM comparator uses the inductor current signal and the error amplifier signal to determine the operating duty cycle. In the MIC3838/9 the signal at the CS pin is level shifted up before it reaches the PWM comparator as shown in Figure 1. This allows operation of the error amplifier and PWM comparator in a linear region. There are two current limit thresholds in the MIC3838/9; peak current limit and overcurrent limit. The normal operating voltage at the ILIM pin is designed less than these thresholds. A pulse-by-pulse current limit occurs when the inductor current signal at the ILIM pin exceeds the peak current limit threshold. The on-time is terminated for the remainder of the switching cycle, regardless of whether OUTA or OUTB is active. If the signal at the ILIM pin goes past the peak threshold and exceeds the overcurrent limit threshold, the overcurrent limit comparator forces the soft start node to discharge and initiates a soft start reset. An internal FET discharges the RAMP and ILIM pins at the end of the oscillator charge time. The FET turns on when the voltage on the RC pin reaches the upper threshold (VDD/2) and remains on for the duration of the RC pin discharge time and for typically 100ns after the start of the next on-time period. The 100ns period at the beginning of the on-time implements a front edge blanking feature that prevents false triggering of the PWM comparator due to noise spikes on the leading edge of the current turn-on signal. The front edge blanking also sets the minimum on-time for OUTA and OUTB. The timing diagram for the RAMP pin is shown in Figure 4.
4
RC VDD 2 S Q R 0.2V OSCILLATOR OUTPUT
Figure 3. Oscillator The voltage source to the resistor/capacitor timing components is VDD. The internal turn-off comparator threshold in the oscillator circuit is VDD/2. This allows the oscillator to track changes in VDD and minimize frequency variations in the oscillator. The oscillator frequency can be roughly approximated using the following formula: 1.41 RxC Where: frequency is in Hz Resistance is in ohms Capacitance is in Farads. FOSCILLATOR =
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MIC3838/3839
MIC3838/3839
Max ON time dead time
Micrel
Output Drivers OUTA and OUTB are alternating output stages, which switch at half the oscillator frequency. A toggle flip-flop in the MIC3838/9 guarantee both outputs will not be on at the same time. The RC discharge time is the dead time, where both outputs are off. This provides an adjustable non-overlap time to prevent shoot through currents and transformer saturation in the power supply. The output drivers are inhibited when VDD is below the undervoltage threshold. Internal circuitry prevents the output drivers from glitching high when VDD is first applied to the MIC3838/9 controller. Decoupling and PCB Layout PCB layout is critical to achieve reliable, stable and efficient operation. A ground plane is required to control EMI and minimize the inductance in power, signal and return paths. The following guidelines should be followed to insure proper operation of the circuit: * Low level signal and power grounds should be kept separate and connected at only one location, preferably the ground pin of the control IC. The ground signals for the current sense, voltage feedback and oscillator should be grouped together. The return signals for the gate drives should be grouped together and a common connection made at the ground pin of the controller. The low level signals and their returns must be kept separate from the high current and high voltage power section of the power supply. * Avoid running sensitive traces, such as the current sense and voltage feedback signals next to or under power components, such as the switching FETs and transformer. * If a current sense resistor is used, it's ground end must be located very close to the ground pin of the MIC3838/9 controller. Careful PCB layout is necessary to keep the high current levels in the current sense resistor from running over the low level signals in the controller. * A minimum 1F bypass capacitor must be connected directly between the VDD and GND pins of the MIC3838/9. An additional 0.1F capacitor between the VDD end of the oscillator frequency setting resistor and the ground end of the oscillator capacitor may be necessary if the resistor is a distance away from the main 1F bypass capacitor
RC Pin
Oscillator Reset
dead time Front edge blanking
RAMP Pin
Minimum ON time
OUTA
OUTB
Figure 4. Timing Diagram Error Amplifier The error amplifier is part of the voltage control loop of the power supply. The FB pin is the inverting input to the error amplifier. The non-inverting input is internally connected to a reference voltage. The output of the error amplifier, COMP, is connected to the PWM comparator. A voltage divider between the error amplifier output (COMP pin) and the PWM comparator allows the error amplifier to operate in a linear region for better transient response. The output of the error amplifier (COMP pin) is clamped at typically 3.65V to prevent the COMP pin from rising up too high during startup or during a transient condition. This feature improves the transient response of the power supply.
MIC3838/3839
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MIC3838/3839
Micrel
Package Information
3.15 (0.122) 2.85 (0.114)
4.90 BSC (0.193)
DIMENSIONS: MM (INCH)
3.10 (0.122) 2.90 (0.114) 1.10 (0.043) 0.94 (0.037)
0.26 (0.010) 0.10 (0.004)
0.30 (0.012) 0.15 (0.006) 0.50 BSC (0.020)
0.15 (0.006) 0.05 (0.002)
6 MAX 0 MIN
0.70 (0.028) 0.40 (0.016)
10-Pin MSOP (MM)
MICREL, INC. 1849 FORTUNE DRIVE SAN JOSE, CA 95131
TEL
USA
+ 1 (408) 944-0800
FAX
+ 1 (408) 944-0970
WEB
http://www.micrel.com
The information furnished by Micrel in this datasheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer. Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser's use or sale of Micrel Products for use in life support appliances, devices or systems is at Purchaser's own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. (c) 2003 Micrel, Incorporated.
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MIC3838/3839

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