CP3800 CERAMATE | Alldatasheet
Document overview
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Technical content
Features
- Wide supply voltage operating range: 1.8 to13 V
- Low current consumption: Typically 5.5 mA in operation, 1 µA or less in stand-by
- High speed operation is possible: Maximum
1 MHz
- The error amplifier gain is set inside the IC, so peripheral components are minimized.
- Incorporates a soft start circuit.
- Incorporates a timer-latch type short circuit detection circuit (SCP).
- Totem-pole type output with adjustable on/off current (for NPN transistors)
- Incorporates a stand-by function.
Applications
- Power source for battery-powered equipment
- Power source for cameras, camcorders, VCRs, PDAs, electronic data banks, and hand-held Communication equipment General Description The CP3800 is a s ingle-channel switching regulator control IC for low voltage applications incorporating a soft start function and short circuit detection function. The device has a low minimum operating voltage of 1.8 V and is ideal for the power supply of battery-operated electronic equipment. The CP3800 can be operated on two types: non- insulated input/output choppers (step-up, step- down , and insulated input/output converters (f ly- back). The former type is used for DC/DC converters and the latter type is used for DC/DC converts and line-operation-type power supplies. Block Diagram CP3800 Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 1 of 19 Rev 1.0 Mar.31,2003
Pin No. Symbol I/O Description
1 IN- I Error amplifier inverting input pin
2 SCP — Soft start and SCP setting capacitor connection pin
3 VCC — Power supply pin
4 BR/CTL I Output current setting and control pin
5 OUT O Totem-pole type output pin
6 GND — Ground pin
7 OSC — Capacitor and resistor connection pin for setting the oscillation
8 FB O Error amplifier output pin
- All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 2 of 19 Rev 1.0 Mar.31,2003 CP3800 Switching Regulator Power Controller
Ordering Information
N: DIP-8 BLANK: TUBE S: SOP-8 A: TAPING T: TSSOP-8
(Ta=+250C) Rated ValueParameter Symbol Condition Min. Max. Unit Power supply voltage V CC —— 3 V Output source current I O + —— - 5 0 m A Output sink current I O - —— 5 0 m A PD SOP-8, Ta ≦+25°C —5 7 0 m W Allowable dissipation PD TSSOP-8, Ta ≦+25°C —4 3 0 m W Operating temperature T OP —- 3 0 + 8 5 0C Storage temperature T stg — -55 +125 0C ESD Classification MIL-STD-883 Class 2 * : When mounted on a 10 cm square double-sided epoxy board WARNING: Semiconductor devices can be permanently damaged by application of stress (voltage, current, temperature, etc.) in excess of absolute maximum ratings. Do not exceed these ratings. Recommended Operating Conditions (Ta=+250C) ValuesParameter Symbol Min. Typ. Max. Unit Power supply voltage V CC 1.8 -- 12.0 Ｖ Error amplifier input voltage V I -0.2 -- 1.0 Ｖ BR/CTL pin input voltage V BR -0.2 -- V CC Ｖ Output source current I O + -20 -- -- ｍＡ Output sink current I O - -- -- 40 ｍＡ SCP pin capacitance C PE -- 0.1 -- μＦ Phase compensation capacitance C P -- 0.1 -- μＦ Output current setting resistance R B 150 390 5000 Ω Timing resistance R T 1.0 3.0 10.0 ｋΩ Timing capacitance C T 100 270 10000 pF Oscillation frequency f OSC 10 500 1000 kHz Operating temperature T OP -30 +25 +85 °C WARNING: Recommended operating conditions are normal operating ranges for the semiconductor device. All the device’s electrical characteristics ar e warranted when operated within these ranges. Always use semiconductor devices within the r ecommended operating conditio ns. Operation outside these ranges may adversely affect reliability and could result in device failure. CP3800 Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 3 of 19 Rev 1.0 Mar.31,2003
Electrical Characteristics
(V CC=+2V , Ta=+250C) ValuesParameter Symbol Condition Min. Typ. Max. Unit Reset voltage V R -- -- 0.9 VCircuit to prevent malfunction at low input voltage (U.V .L.O.) Threshold voltage V TH -- 1.1 1.3 1.5 V Charging current I CS VSCP=0V -1.5 -1.0 -0.7 μA Soft start V oltage at soft start completion V Charging current I CPC VSCP=0V -1.5 -1.0 -0.7 μAShort circuit detection (S.C.P.) Threshold voltage V tPC -- 0.7 0.8 0.9 V Oscillation frequency f OSC RT=3.3kΩ, CT=270pF 400 500 600 kHz Frequency input Stability f dV VCC=2V to 12V -- 2 10 %Sawtooth wave oscillator (OSC) Frequency variation with temperature f dT Ta =-300C to 850C- - 5 - - % Input threshold V oltage V T VFB = 450mV 480 500 520 mV VT input stability V TdV VCC=2V to 12V -- 5 20 mV VT variation with Temperature VTdT Ta = -300C to 850C- - 1 - - % Input bias current I B VIN = 0V -1.0 -0.2 1.0 μA V oltage gain A V -- 70 100 145 V/V Frequency bandwidth BW A V = 0 dB -- 6 -- MHz VOM + 0.78 0.87 -- VMaximum output voltage range V OM -- 0.05 0.2 V Output source current I OM + -- -40 -24 μA Error amplifier Output sink current I OM VFB = 450mV 24 40 -- μA Idle period adjustment section Maximum duty cycle T DUTY RT=3.3kΩ, CT=270pF fOSC = 500KHz 75 -- 85 % VOH1 RB= 390Ω, IO= -15 mA 1.0 1.2 -- V VOH2 RB= 750Ω, VCC = 1.8V IO= -10 mA 0.8 1.0 -- V VOL1 RB= 390Ω, IO= -15 mA -- 0.1 0.2 V Output voltage VOL2 RB= 750Ω, VCC = 1.8V IO= -10 mA -- 0.1 0.2 V Output source current I O Output sink current I O - RB= 390Ω, VO = 0.3V 30 60 -- mA Output section Pull down resistance R O -- 20 30 40 ｋΩ CP3800 Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 4 of 19 Rev 1.0 Mar.31,2003
Pin voltage V BR RB= 390Ω 0.10 0.19 0.25 V Input off condition I OFF -20 -- 0 μA Input on condition I ON -- -- -45 μA Output current Setting section/ Control section Pin current range I BR -1.8 -- -0.1 ｍＡ Stand-by current I CCS BR/CTL pin open or V CC -- -- 1 μA Entire device Average supply current I CC RB= 390,VCC =2~12V -- 5.5 10.0 ｍＡ Timing Chart CP3800 Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 5 of 19 Rev 1.0 Mar.31,2003 t S t PE ON OFF FB pin voltage Reference input for short circuit detection comparator Idle period setting voltage Sawtooth wave output Soft start setting voltage OUT pin waveforms SCP pin waveforms Power supply control SW Soft start Output short circuit Output short circuit Short circuit detection
Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 6 of 19 Rev 1.0 Mar.31,2003
Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 7 of 19 Rev 1.0 Mar.31,2003
Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 8 of 19 Rev 1.0 Mar.31,2003
Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 9 of 19 Rev 1.0 Mar.31,2003
Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 10 of 19 Rev 1.0 Mar.31,2003
Typical Application Schematic CP3800 Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 11 of 19 Rev 1.0 Mar.31,2003
Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 12 of 19 Rev 1.0 Mar.31,2003
Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 13 of 19 Rev 1.0 Mar.31,2003
Figure 1 Soft-Start SCP Equivalent circuit At power-on, the CP3800 operates in the soft-start mode. Since no current is supplied, comp1, comp2, and SCP latch are inactive. Immedi ately after power-on, the CPE cap acitor is charged at a constant current of 1µA to increase from 0V . In the soft-start mode, the VSCP (capacitor CPE voltage) is input to the PWM comparator, so that the soft-start circu it is controlled at the on-duty ratio of 0% with the increase of the VSCP. When the VSCP reaches 0.8V , the soft-start supplies current to comp1, comp2, and SCP latch and at the same time discharges the CPE capacitor (VSCP= 0V). This changes the soft-start mode to the normal mode (output short circuit detection wait stat e) and the SCP becomes active (stays low). In the normal mode, the input from the soft-start circuit to the PWM comparator is kept at 0.8V . If the switching regulator output suddenly drops due to load effect, the error amplifier output (FB pin) is fixed at VOM + and capacitor CPE starts charging. Wh en the voltage at the SCP pin reaches approximately 0.8V , the output pin is set low and the SCP pin stays low. Set time by the following expressions (see Timing Chart): Soft-Start time (The time until the output ON duty reaches approximately 50%) CP3800 Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 14 of 19 Rev 1.0 Mar.31,2003
Short-circuit detection time(or Soft-Start full time) : Setting Oscillating Frequency The oscillation frequency of a sawtooth waveform is determined by the timing capacitor (CT) and the timing resistor (RT) which are connected to the OS C pin. When the voltage of the OSC pin falls to 0.1V , the CT is rapidly charged to increase the voltage of the OSC pin instantaneously. When the voltage of the OSC pin reaches 0.8V , Charging stops, so that CT and RT are discharged to decrease the voltage of the OSC pin. The waveform of the OSC pin is shown as Figure 2. Figure 2 Oscillator Waveform The cycle (T) can be determined as follows: Calculating under the conditions of RT=3.0KΩ and CT=270pF , the oscillating frequency is 588kHz, which is slightly different from the value (600kHz) in the Electrical Characteristics. This difference is caused by characteristics, such as changes in the maximum voltage amplitude of the sawtooth waveform with the CT value and the circuit delay causing the maximum amplitude to become large in the case of a high oscillating frequency even for the same capacitor. It is difficult to incorporate these non-linear characteristics into the equa tion. In practical use, therefore, the user should read the RT and CT values from the characteristic cu rve or should determine an approximate target value by using the equation. ) ( 35 . 0F CPE tS µ× = ) ( 8 . 0F CPE tPE µ× = RT CT t VHe VX× = ) ( logVH VXRT CT te× × − = CP3800 Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 15 of 19 Rev 1.0 Mar.31,2003
Switching Regulator Function (1) Reference voltage circuit The reference voltage circuit generates a temperature-compensated reference voltage (~1.25V) from voltage supplied from the power supply pin (pin 3). In addition to providing the reference voltage for the switching regulator, the circuit also sets the idle period. (2) Error amplifier The error amplifier detects the output voltage of the switching regulator and outputs the PWM control signal. The voltage gain is fixed, and connecting a phase compensation capacitor to the FB pin (pin 8) provides stable phase compensation for the system. (3) PWM comparator The voltage comparator has one inverting and three non-inverting inputs. The comparator is a voltage/pulse width converter that controls the ON time of the output pulse depending on the input voltage. The output level is high (H) when the sawtooth wave is lower than the error amplifier output voltage, soft start setting voltage, and idle period setting voltage. (4) Output circuit The output circuit has a totem pole type configuration and can drive an external NPN transistor directly. The value of the ON/OFF current can be set by a resistor connected to the BR/CTL pin (pin 4). Stand-by mode (supply current 1µA or less) can be set by connecting the BR/CTL pin (pin4) to VCC or by making the pin open circuit. (5) Under-Voltage Lockout (UVLO) Transients when powering on or instantaneous glitches in the supply voltage can lead to malfunction of the control IC and cause system damage or failure. The circuit to prevent malfunction at low input voltage detects a low input voltage by comparing the supply voltage to the internal reference voltage. On detection, the circuit fixes the output pin to low. To cancel the status, set VCC below the reset voltage VR (0.9V) and then set VCC up to the recommended operation condition range. By the operation, the latch is canceled to start to operate normally. CP3800 Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 16 of 19 Rev 1.0 Mar.31,2003
Small Outline 8-pin Plastic SOP INCHES MILLIMETERSSYMBOL MIN MAX MIN MAX NOTES A 0.188 0.197 4.80 5.00 - B 0.149 0.158 3.80 4.00 - C 0.228 0.244 5.80 6.20 - D 0.050 BSC 1.27 BSC - E 0.013 0.020 0.33 0.51 - F 0.004 0.010 0.10 0.25 - H 0.053 0.069 1.35 1.75 - J 0.011 0.019 0.28 0.48 K 0.007 0.010 0.19 0.25 - M 0.016 0.050 0.40 1.27 L 0.150 REF 3.81 REF - e1 45 0 450 - α 00 80 00 80 - CP3800 Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 17 of 19 Rev 1.0 Mar.31,2003
INCHES MILLIMETERSSYMBOL MIN MAX MIN MAX NOTES A 0.114 0.122 2.90 3.10 - B 0.169 0.177 4.30 4.50 - C 0.244 0.260 6.20 6.60 - D 0.026 BSC 0.65 BSC - E 0.010 0.012 0.25 0.30 - F 0.002 0.006 0.05 0.15 - H 0.041 0.047 1.05 1.20 - K 0.005 BSC 0.127 BSC - M 0.020 0.028 0.50 0.70 α 00 80 00 80 - CP3800 Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 18 of 19 Rev 1.0 Mar.31,2003
Reflow Condition (IR/Convection or VPR Reflow) Reference JEDEC Standard J-STD-020A Classification Reflow Profiles Convection or IR/Convction VPR Average Heating Rate(180°C to peak) 5 °C/second max. 10 °C/second max. Preheat Temperature(125±20°C) 120 seconds max. Temperature maintained above 180°C 10~150 seconds Time within 5°C of actual Peak Temperature 10~20 seconds 60 seconds Peak Temperature Range(Note 1) 219~225°C or 235~240°C 219~225°C or 235~240°C Cooling Rate 6°C /second max. 10 °C/second max. Time 25°C to Peak Temperature 6 minutes max. *1 The maximum peak temperatures for IR and VP reflow are depending on package dimensions. Package Reflow Conditions Pkg. Thickness ≥2.5mm and all bags Pkg. Thickness <2.5mm a n d Pkg. Volume ≥350 mm3 Pkg. Thickness <2.5mm a n d Pkg. Volume <350 mm3 Convection 219~225°C Convection 235~240 °C VPR 219~225°C VPR 235~240 °C IR/Convection 219~225°C IR/Convection 235~240 °C CP3800 Switching Regulator Power Controller * All specs and applications shown above subject to change without prior notice. Tel:886-3-3214525 Http: www.ceramate.com.tw Fax:886-3-3521052 Page 19 of 19 Rev 1.0 Mar.31,2003