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ICs for CD/CD-ROM Player
AN8086S
Low Voltage Operation IC for DC-DC Converter
s Overview
The AN8086S is an IC for controlling a DC-DC converter suitable for the switching power supply of various portable equipment. It can operate with input voltage 1.1V or more. The AN8086S is based on AN8083S with the output voltage in the secondary side changed to 3.6V.
0.4 1 2 3 0.4±0.25 4 5 1.27 6 7 8 16 15 14 13 12 11 10 9 1.5±0.2 0.3 4.2±0.3 6.5±0.3 VREF 12 0.85V 0.25V + 3.24V + 2.7V 2.5V 4.8V Starter SW Early Value Set. 2.0V 0.7V 1.25V + + + + 0.725V 0.9V 6 63k GND Power Off Switching Circuit 8 PVCC Starter Triangular Wave 9 CLK 11 POWER 0.15 0.65 10.1±0.3 Unit : mm
s Features · Operatable with low voltage input (PVCC>1.1V) · Decreased voltage detection circuit built-in · Short-circuit protection feature built-in · Provided with reset output · Synchronizable with outside clock · Low consumption current in stand-by mode
s Block Diagram
RESET VCC 15 16 EMP 13 2.2V VSEN 14 VREF START 10 CT 7
+
30k
1 IN
2 FB
3 SPRO
4 DED
5 OUT
0.1±0.1
16-lead SOP package (SOP016-P-0225A)
ICs for CD/CD-ROM Player
s Absolute Maximum Ratings (Ta=25°C)
Parameter Supply Voltage Power Dissipation Operating Ambient Temperature Storage Temperature Symbol VCC PVCC PD Topr Tstg Rating 14.4 14.4 380 20 ~ +75 55 ~ +125
AN8086S
Unit V mW °C °C
s Recommended Operating Range (Ta=25°C)
Parameter Operating Supply Voltage Range Symbol VCC PVCC Range 3.6V ~ 12V 1.1V ~ 12V
s Electrical Characteristics (Ta=25°C)
Parameter Power VCC Stand-by Mode Supply Current Power VCC No Load Supply Current Output Voltage Reset Output Threshold Voltage Decreased Voltage Detection Threshold Voltage Short-Circuit Protection Operating Voltage Short-Circuit Protection Operating Voltage Triangular oscillation Frequency in Normal Operation Triangular oscillation Frequency at Start Output Voltage Output Voltage Symbol IPVCC IPVCC VO VTH (RESET) VTH (VSEN) VO (SPRO) VO (SPRO) fOSC1 fOSC2 VOH (OUT) VOL (OUT) VIN=0V, VPOWER=2V VIN=1V, VPOWER=0V RREF=33k, CT=330pF RREF=33k, CT=330pF VCC=1.9V, PVCC=3V IO=20mA, VCT=0V IO=20mA, VCT=1V VTH × 0.85 2.1 1.35 1.7 60 80 1.2 70 100 Condition VCC=0V, PVCC=3V VCC=3.1V, PVCC=3V 1.2 3.6 VTH × 9 VTH × 0.95 2.2 2.3 2.1 3.2 80 120 1.6 0.4 min. typ. max. 2 3 Unit µA mA V V V V V kHz kHz V V
Note) Unless otherwise specified, VCC =4.8V, PVCC=3V
s Application Circuit Example
3.6V 330pF VREF 33k 12
RESET VCC EMP 15 16 13
VSENSE 2.2V
START 14 VREF 10
CT 7
0.85V 0.25V
+
+
Starter 2.7V 2.5V
3.24V
Triangular Wave
CLK 9 PVCC 8 POWER
4.8V
Starter SW Early Value Set. 2.0V 0.7V 1.25V
+ + + +
Power OFF Swiching Circuit
11
25µA 30k 0.9V 0.725V
+
GND 6 63k 0.01µF
1 IN 33k
2 FB + 0.01µF
3 SPRO 47µF
4 DED 0.01µF
5 OUT
100
ICs for CD/CD-ROM Player
s Pin Description
Pin No. 1 2 Symbol IN FB · Input pin for error amplifier · Threshold voltage ; 0.7V · Output pin for error amplifier Description
AN8086S
3
SPRO
· Short-circuit protection input pin If output of error amplifier does not become "L" when t = CVth/ISPRO output of IC is not switched. ISPRO =25µA Vth = 0.9V · Dead time control input Maximum duty ratio set to 85%. · Switching output pin Output current ; IO=20mA (max.) · GND pin · Triangular oscillating capacitor pin CV CV T2 = I (Discharged) I (Charged)
4 5 6
DED OUT GND
T1 = 7 CT
V
f=
T1 T2
1 T1 + T2
I (Discharged) =52µA I (Charged) =30µA V = 0.58V In normal operation
8
PVCC
· DC voltage input pin Operates with 1.1V or more. · Clock input · It is used to synchronize triangular oscillation with clock input and operates at rise edge of clock. · The threshold level is TTL level. · It is open when not used. · Start pin · Starts switching of starter (start at "L") · Threshold voltage, PVCC 0.9V · Power ON/OFF pin Output ON/OFF switching pin (Output is off at "L.") · Reference voltage pin · 1.25V output · Charged and discharged current of triangular oscillation is determined by external R. V 0.7 I (Charged) = REF RREF +1k I (Discharged)=1.40 × I (Charged) · Decreased voltage detection output pin "H" when detected by open collector output form · Decreased voltage detection input pin · Threshold voltage ; 2.2V · Reset output pin · "H" when VCC becomes VO × 0.9V or more · Open collector output form · DC voltage input pin Operates with 3.6V or more.
9
CLK
10
START
11
POWER
12
VREF
13 14
EMP VSEN
15
Reset
16
VCC