AN8018 Panasonic Semiconductor, AN8018 Datasheet
AN8018
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AN8018 Summary of contents
Page 1
... AN8018SA 1.8-volt 2-channel step-up, step-down, or inverting DC-DC converter control IC Overview The AN8018SA is a two-channel PWM DC-DC con- verter control IC that features low-voltage operation. This IC can obtain the step-up, step-down and invert- ing voltages with a small number of external components. The minimum operating voltage is as low as 1 that it can operate with two dry batteries ...
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... AN8018SA Block Diagram On/ 15 Reference On/off off voltage source control V 5 FB1 Error amp 0 FB2 S.C.P. comp. 0.22 V Error amp 1.19 V Pin Descriptions Pin No. Symbol Description 1 OSC Pin for oscillation timing resistor and capacitor connection 2 S.C.P. Pin for connecting the time constant set- ...
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... SCP REF Symbol Conditions V I 0.1 mA REF REF Line V 1 Load I 0 REF AN8018SA Rating 135 150 Range 1 (minimum) 70 (maximum 100 to 10 000 000 180 to 15 000 ...
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... AN8018SA Electrical Characteristics at V Parameter U.V.L.O. block Circuit operation start voltage Error amplifier 1 block Input offset voltage Common-mode input voltage range Input bias current 1 High-level output voltage 1 Low-level output voltage 1 Output source current 1 Output sink current 1 Error amplifier 2 block Input threshold voltage ...
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... CHG SCP V ON(TH 820 duty 0% CC(OFF 820 CC(LA CC(SB) Symbol Conditions REFdT THdT AN8018SA 25 C (continued) Min Typ Max Unit 0.65 0.72 0.28 0.30 1.1 0.5 0.15 0.20 0.25 0.8 0.9 1.0 60 120 mV 0.8 0.9 1.0 0.17 0.22 0.27 60 120 mV 1.43 1.1 0.77 0.8 1.0 1.3 5.7 8.0 mA 5.6 7 Min Typ ...
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... AN8018SA Electrical Characteristics at V Design reference data (continued) Note) The characteristics listed below are theoretical values based on the IC design and are not guaranteed. Parameter Output 2 block RB terminal voltage Short-circuit protection block Comparator threshold voltage On/off control block Off terminal current Terminal Equivalent Circuits Pin No ...
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... RB2 pin. I SO(OUT)2 RB2: The pin for connecting a resistor for setting chan- nel 2 output current. Use a resistance value in the range of 180 k . Out2 The terminal voltage is 0.36 V (at R AN8018SA Description V RB2 68 [ 1.1 820 ). B2 I/O I ...
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... AN8018SA Terminal Equivalent Circuits (continued) Pin No. Equivalent circuit 0.9 V FB2 0 1. 100 DT2: The pin for setting channel 2 output maximum duty ratio. If this terminal is set at a voltage of 0 more, OSC PWM FB2 terminal becomes high-level voltage and the protective function for channel 2 output short- circuit will stop (Unlatch function) ...
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... V terminal current (8.0 mA maximum but [2] Since the output 2 of the AN8018SA is assuming the bipolar transistor driving necessary to pay attention to the following points when directly driving n-channel MOSFET. 1. Select an n-channel MOSFET having a low input capacitance The AN8018SA is of the constant-current (50 mA maximum) output source-current type circuit assum- ing the bipolar transistor driving ...
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... AN8018SA Usage Notes (continued) [4] (continued) Application Notes [ curves of SSOP016-P-0225A D a [2] Main characteristics V temperature characteristics REF 1.195 1.190 1.185 ripple allowable range CC 100 10 2 Recommended operating range 1 0.5 0.1 0 0.3 0 ripple width (V[p-p 700 600 ...
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... V ( 100k 100 100 0.2 0.7 0 100 AN8018SA I R SI(OUT 2 1 10k 100k DT2 0.3 0.4 0.5 0.6 0.7 0.8 V (V) DT2 I R CC(OFF ...
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... AN8018SA Application Notes (continued) [3] Timing chart (inside waveform) V terminal CC voltage waveform 1.6 V S.C.P. terminal voltage waveform Channel 1 Out1 terminal voltage waveform Open-collector output Channel 2 Out 2 terminal voltage waveform Totem pole output 12 Output short-circuit FB1 OSC DT1 FB2 OSC DT2 Voltage Regulators 1.22 V ...
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... OSCL T T OSCH can be set by making connection as shown in figure 2. V REF PWM R2 R4 comparator input V OUT1 R3 R4 · · V REF R4 AN8018SA V OSCH V OSCL Discharging T Case of inverting output FB2 5 Error amplifier 1 block PWM comparator input R1 R2 ...
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... AN8018SA Application Notes (continued) [4] Function descriptions (continued) 4. Error amplifier 2 block (continued) Also possible to perform the gain setting and the phase compensation arbitrarily by con- necting a resistor and a capacitor from the FB2 terminal (pin 13) to GND in series. The output voltage V OUT2 ing connection as shown in figure 3. ...
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... OSC FB1 FB2 Out1 (Open-collector output) Out2 (Totem pole output) Channel 1 Switching transistor emitter current I E1 Channel 2 Switching transistor collector current Figure 4. PWM logic explanation chart AN8018SA DT1 and DT2 are omitted SBD SBD 15 ...
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... AN8018SA Application Notes (continued) [6] Time constant setting method for timer latch short-circuit protection circuit The constructional block diagram of protection latch circuit is shown in figure 6. The comparator for short-circuit protection compares the error amplifier 1 output FB1 with the reference voltage of 0.9 V for channel 1 side, and the error amplifier 2 output FB2 with the reference voltage of 0 ...
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... Multiple instances of this IC can be operated in parallel. If the OSC terminals (pin 1) and Off terminals (pin 15) are connected to each other as shown in figure 7, the ICs will operate at the same frequency possible to operate this IC (the AN8018SA) with the two-channel totem pole output IC AN8017SA in parallel synchronous mode. ...
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... AN8018SA Application Notes (continued) [7] Parallel synchronous operation of multiple ICs (continued) 2. About the operation of short-circuit protection at parallel synchronous operation In the case of the operation in parallel, if the single output (or multiple outputs) of them is short-circuited and the timer latch short circuit protection of the IC is operated, the output of other ICs will be also shut down, then enter into latch mode ...
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... FB2 terminal (pin 13) becomes fixed to high even if output of channel 2 downs. 0.9 V 1.19 V CTL R OFF at which the start CTL CTL Q2 Unlatch2 0.9 V Unlatch1 0.2 V Figure 10 AN8018SA Off 15 Start circuit Figure 9. Off terminal peripheral circuit V 2 Control block ...
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... AN8018SA Application Notes (continued) [9] About sequential operation (continued DT1 Out1 DT2 Out2 [10] Error amplifier phase-compensation setting method The equivalent circuit of error amplifier is as shown in figure 11. The transfer function is The cut-off frequency is variable by changing the externally attached phase compensation capacitor C Adjust by inserting a resistor R required to have a gain on the high frequency side or desired to lead a phase ...
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... C 0. 100 10M 100M 1 AN8018SA 100 000 100 1k 10k 100k 1M 10M 100M f Hz 000 ...
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... AN8018SA AC Analysis Result (continued) f Phase 180 160 0.001 F 140 0.01 F 120 0.1 F 100 100 1k 10k 100k f Hz) f Gain 60 40 0.001 F 20 0. 100 1k 10k 100k f Hz) 22 180 160 140 120 100 80 60 ...
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... AN8018SA R6 R12 OUT1 VIN R16 R14 R18 SBD2 R17 C9 Q3 R15 L2 C12 C5 C11 R10 R8R7 R11 R12 AN8018SA L2 SBD V OUT2 Q3 C10 R11 Q1 V SBD R13 On SW1 Off AN8018SA R17 R18 OUT1 23 ...
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... AN8018SA 1 k 0.01 200 0. 0 Input 0 AN8018SA 1 k 0.01 0.01 F 560 0 Voltage Regulators Output 2 100 MA3X720 (MA720 2SD0602 (2SD602*) 510 Output MA3X720 ...
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... Input 0 0 AN8018SA 1 k 0.01 560 F 750 68 k MA3X720 0 (MA720*) AN8018SA 100 H V OUT2 15 V MA3X720 150 k (MA720 2SD0602 (2SD602*) f 200 kHz 2SA1022 OUT1 (0 0 ...
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... AN8018SA Application Circuit Examples (continued) Application circuit example 4 (Circuit using the AN8017SA/AN8018SA) Input voltage range: 1 3.2 V Oscillation frequency: 450 kHz 0.1 F 1.19 V 330 pF 1.19 V 0.1 F Remote on/off control pin stop with high-level input 0.1 F 0.1 F 820 10 k AN8018SA 10 k 5.1 k ...