View R1250V301A_57866.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

Negative Output Charge Pump Regulator (100mA)
R1250Vxx1A SERIES
APPLICATION MANUAL
NO. EA-076-0012
Negative Output Charge Pump Regulator (100mA)
R1250Vxx1A SERIES
OUTLINE
The R1250Vxx1A Series are Negative Output Charge Pump Regulator ICs, which can be developed as local power suppliers for portable appliances and small electric appliances used with batteries, with low supply current by CMOS process. Each of these ICs consists of an oscillator, a control circuit, a reference voltage unit, an error amplifier, and an output driver circuit. The R1250Vxx1A can easily supply negative voltage, or regulated setting output voltage in the range from -2V to -4V from positive input voltage. The chip enable function works to shut down the internal circuit and reduces supply current at the stand-by mode, therefore the R1250Vxx1A is very suitable for the application such as portable systems that require low supply current. Since the package for this IC is TSSOP8 package (TSOP8 in EIAJ standard), high density mounting of the ICs on board is possible.
FEATURES
* Output Current..................... 100mA (MAX. at VIN=5.0V CIN=CP=COUT=4.7F, Set Output Voltage=-3.0V) , * Output Voltage Accuracy...... 3.0% (VIN=5.0V CIN=CP=COUT=4.7F, Set Output Voltage=-3.0V IOUT=0mA/10mA) , , 9.0% (VIN=5.0V CIN=CP=COUT=4.7F, Set Output Voltage=-3.0V IOUT=50mA) , , * Output Voltage...................... Stepwise setting with a step of 0.1V in the range from -2.0V to -4.0V is possible. * Range of Input Voltage ......... VOUTV to +5.5V (Set Output Voltage=-4.0V to -2.8V) +2.7V to +5.5V (Set Output Voltage=-2.7V to -2.0V) * Oscillator Frequency ............ TYP 280kHz . * Chip Enable Function (Active at "L") * Package ................................. TSSOP8
APPLICATIONS
* Power source for Disk Drives. * Power source for hand-held communication equipment and battery-powered equipment. * Power source for PC peripherals and ADD-ON cards. * Power source for portable audio-visual appliances such as cameras. * Local power source for small electrical appliances.
1
R1250Vxx1A
BLOCK DIAGRAM
CP+ 1 SW1 CP3 SW3 SW4 RO 7 VOUT
VIN
8
2
GND
SW2
OSC RPU CE 4 Vref 6 Vref
PIN CONFIGURATION
TSSOP8
CP+ GND CPCE 1 2 3 4 8 7 6 5 VIN VOUT Vref NC
PACKAGE DIMENSION
1 2 3 4 8 7 6 5
2
R1250Vxx1A
PIN DESCRIPTION
Pin No. 1 2 3 4 5 6 7 8 CP+ GND CP---- CE NC Vref VOUT VIN Symbol Description CP (Capacitor for Charge Pump) Positive Power Supply Pin Ground Pin CP (Capacitor for Charge Pump) Negative Power Supply Pin Chip Enable Pin (active at "L") No Connection Pin Output Pin for Reference Voltage (*Note1) Output Pin for Negative Regulator Power Supply Pin
*Note1 Vref is just a monitoring pin, therefore remain open. Do not connect any load. Refer to Technical Notes.
ABSOLUTE MAXIMUM RATINGS
(GND=0V) Symbol VIN VCE VP+ Vref VPVOUT IOUT PD Topt Tstg Item VIN Supply Voltage ---- CE Pin Input Voltage CP+ Pin Input Voltage Vref Pin Voltage CP- Pin Input Voltage VOUT Pin Voltage Output Current Power Dissipation*NOTE1 Operating Temperature Range Storage Temperature Range Rating -0.3 to 7.5 -0.3 to VIN+0.3 -0.3 to VIN+0.3 -0.3 to VIN+0.3 VIN-12 to +0.3 VIN-12 to +0.3 200 490 -40 to +85 -55 to +125 Unit V V V V V V mA mW C C
*Note1: Power dissipation is specified under the specified condition. Conditions; Evaluation Board Dimensions: 50mm x 50mm x 1.6mm Material: Glass Epoxy (FR-4) Reverse side of the evaluation board: Plane Copper Surface of the evaluation board: Land pattern and Wiring
3
R1250Vxx1A
SELECTION GUIDE
The output voltage and the active type for the ICs can be selected at the user's request. The selection can be made with designating the part number as shown below; R1250Vxx1A-xx a bc Code Setting Output Voltage a xx: The absolute value of Output Voltage Stepwise setting with a step of 0.1V in the range of -2.0V to -4.0V is possible. b c Designation of Active Type of the Chip Enable Circuit: A (fixed) : "L active type " Designation of Packing Type E2 : E2 1reel=2000pcs Contents
4
R1250Vxx1A
ELECTRICAL CHARACTERISTICS
R1250Vxx1A Symbol VIN Item Operating Input Voltage (Unless otherwise provided, VIN=5.0V Topt=25C, CP, COUT = Ceramic 4.7F) , Conditions Set Output Voltage = -2.7V to -2.0V Set Output Voltage = -4.0V to -2.8V -2.4V to -2.0V ISS Supply Current Operation: Active, for IC itself *Note1 -2.9V to -2.5V -3.4V to -3.0V -4.0V to -3.5V ISTB Shut-down Current Operation: Shut-down, for IC itself *Note2 -2.4V to -2.0V IOUT=0mA/10mA -2.9V to -2.5V -3.4V to -3.0V -4.0V to -3.5V IOUT=50mA -2.4V to -2.0V -2.9V to -2.5V IOUT=75mA -3.4V to -3.0V -4.0V to -3.5V Vref VOUT/ IOUT fosc fosc/T Duty VSDH VSDL RPU RO
*Note1
MIN. 2.7 |Set VOUT|
TYP.
MAX. 5.5
Unit V
1.50 1.60 1.70 1.80 0.1 x0.95 x0.96 x0.97 x0.97 x0.88 x0.89 x0.91 x0.92 VOUT 0.7 238 280 0.25
2.30 2.55 2.75 3.00 1 x1.05 x1.04 x1.03 x1.03 x1.12 x1.11 x1.09 x1.08 V mV/ mA 322 kHz kHz/ C % V 0.25 V M k V A mA
VOUT
Output Voltage
Reference Voltage*Note3 Load Regulation Oscillator Frequency Oscillator Frequency Temperature Coefficient Oscillator Duty Cycle CE "H" Input Voltage CE "L" Input Voltage CE Pull-up Resistance Resistance between VOUT and GND
Refer to Test Circuit 1.
No load IOUT=10mA to 50mA -2.4V to -2.0V IOUT=10mA to 75mA -4.0V to -2.5V Output Frequency
At no Load 1.5
50
0.68
1.25 5
3.00
*Note2: Refer to Test Circuit 6. *Note3: Do not connect ant load. Refer to Technical Notes. *Use Ceramic Capacitors with low ESR. Capacitors with high ESR could have bad effect on the performance of this IC.
5
R1250Vxx1A
TYPICAL CHARACTERISTICS
1) Supply Current at no load vs. Input Voltage R1250Vxx xx1A xx
2.500
2)
Supply Current at no load vs. Temperature R1250Vxx xx1A xx
2.5
Supply Current at no load ISS2 (mA)
Supply Current at no load ISS2 (mA)
-4.0V Output 2.000 -3.0V Output
-4.0V Output 2.0
1.500
1.5
1.000 -2.0V Output 0.500
1.0 -2.0V Output 0.5 -3.0V Output
0.000 2.5
3.0
3.5 4.0 4.5 Input Voltage VIN (V)
5.0
5.5
0.0 -50
-25
0 25 50 Temperature Topt (C)
75
100
3)
Input Current vs. Output Load Current R1250V301A
120 100
Input Current IIN (mA)
4)
Efficiency vs. Load Current R1250Vxx xx1A xx
100 -4.0V Output 80
Efficiency (%)
80 60 40 20 0 0 20 40 60 80 100 Output Load Current IOUT (mA) 120
60 -2.0V Output 40 -3.0V Output VIN=lOutputl+1V
20
0 0 20 40 60 80 100 120 Output Load Current IOUT (mA)
5)
Oscillator Frequency vs. Input Voltage R1250V201A
320
6)
Oscillator Frequency vs. Temperature R1250V201A
300
Oscillator Frequency fosc (kHz)
Oscillator Frequency fosc (kHz)
310 300 290 280 270 260 250 240 2.5
298 296 294 292 290 288 286 284 282 280 -50 -25 0 25 50 75 100
3
3.5 4 4.5 Input Voltage VIN (V)
5
5.5
Temperature Topt (C)
6
R1250Vxx1A
7)
Output Voltage vs. Output Load Current R1250V201A
-1.9
R1250V201A
-1.5 -1.6
Output Voltage VOUT (V)
85C 50C
Output Voltage VOUT (V)
-1.7 -1.8 -1.9 VIN=3.0V -2 -2.1 25C
-2 VIN=5.0V 25C 50C 85C
-2.1 0 20 40 60 80 100 Output Load Current IOUT (mA) 120
-2.2 0 20 40 60 80 100 Output Load Current IOUT (mA) 120
R1250V301A
-2.9
R1250V301A
-2.5 -2.6 85C 50C 25C
Output Voltage VOUT (V)
Output Voltage VOUT (V)
-2.7 -2.8 -2.9 -3
-3 VIN=5.0V 25C 50C 85C
VIN=4.0V -3.1
-3.1 0 20 40 60 80 100 Output Load Current IOUT (mA) 120
-3.2 0 20 40 60 80 100 Output Load Current IOUT (mA) 120
R1250V401A
-3.5 85C -3.6
Output Voltage VOUT (V)
-3.7 -3.8 -3.9 -4 -4.1 -4.2 0
50C 25C
VIN=5.0V
20 40 60 80 100 Output Voltage Load Current IOUT (mA)
120
7
R1250Vxx1A
8)
Output Voltage vs. Temperature R1250V201A
-1.98
-2.99 -3.00
R1250V301A
Output Voltage VOUT (V)
-1.99
Output Voltage VOUT (V)
-3.01 -3.02 -3.03 -3.03
-2.00
-2.01
-2.02 -50
-25
0 25 50 Temperature Topt (C)
75
100
-3.05 -50
-25
0 25 50 Temperature Topt (C)
75
100
R1250V401A
-3.98 -3.99
Output Voltage VOUT (V)
-4.00 -4.01 -4.02 -4.03 -4.04 -4.05 -4.06 -50
-25
0 25 50 Temperature Topt (C)
75
100
9)
Output Voltage Waveform Unless otherwise provided, conditions are as follows; Sample: R1250V301A VIN=5.0V CIN=CP=COUT=4.7F
-3.00V 100mV 1.00s
IOUT=0mA BW=20MHz
8
R1250Vxx1A
IOUT=10mA
-3.00V
100mV 1.00s
IOUT=50mA
-3.00V
100mV 1.00s
TEST CIRCUITS
Test Circuit 1) Supply Current 1 Test Circuit 2) Typical Characteristics 1), 2) Test Circuit 3) Typical Characteristics 3), 4), 7), 8) Test Circuit 4) Typical Characteristics 5), 6) Test Circuit 5) Typical Characteristics 9) Test Circuit 6) Standby Current 1) Test Circuit 1
ISS-P 1.CP+ 2.GND 3.CP4.CE 8.VIN 7.VOUT 6.Vref 5.NC A Set Output Voltage+0.2V ISS-N A
5.5V
ISS1=ISS-P+ISS-N (*) To stabilize voltage, a few F bypass capacitors are applied to VOUT pin and VIN pin.
9
R1250Vxx1A
2)
Test Circuit 2
ISS2 1.CP+ 2.GND 4.7F 3.CP4.CE 6.Vref 5.NC 4.7F 4.7F 8.VIN 7.VOUT A
3)
Test Circuit 3
IIN 1.CP+ 2.GND 4.7F 3.CP4.CE 6.Vref 5.NC IOUT 4.7F V 4.7F 8.VIN 7.VOUT A
(|VOUT|xIOUT)/(VINxIIN)x100(%) 4) Test Circuit 4
1.CP+ 2.GND Oscilloscope 3.CP4.CE 8.VIN 7.VOUT 6.Vref 5.NC
(*) To stabilize voltage, a few F bypass capacitor is applied to VIN pin.
10
R1250Vxx1A
5)
Test Circuit 5
1.CP+ 2.GND 4.7F 3.CP4.CE 6.Vref 5.NC IOUT 4.7F 4.7F 5.0V 8.VIN 7.VOUT IIN A
Oscilloscope
BW:20MHz
6)
Test Circuit 6
1.CP+ 2.GND 3.CP4.CE 8.VIN 7.VOUT 6.Vref 5.NC A 7.5V
TYPICAL APPLICATION
CIN 4.7F CP+ CP 4.7F GND CPCE VIN Output VOUT Vref NC Open COUT 4.7F
(*) Vref pin should not be wired. Refer to Technical Notes.
11
R1250Vxx1A
OPERATION
1) Basic Operation The R1250Vxx1A Series make SW1 through SW4 ON and OFF by the clock generated by internal oscillator (OSC) with fixed frequency, and operate as a inverting charge pump with the capacitor CP and the capacitor COUT. The Output Voltage is feedback and the voltage between the Output Voltage and Reference Voltage (Vref =VOUT V) is divided half, and it is compared with the GND (=0V) level by an internal operational amplifier. By this action, the impedance of SW3 is controlled to correspond with its load current and Output Voltage keeps "Set VOUT" level. 2) Status of Internal Circuits at Standby mode and Standby Current At Standby mode, R1250V Series keep the voltage of CP as shown below:
VIN
CIN
CP RO up to 5k
ROUT
COUT
VOUT R1250Vxx1A
When you design a system with using this IC, consider the following subjects; 2-(1) If very small leakage current would be a critical, the leakage current of both CIN and CP should be considered. 2-(2) Because the voltage level of CP keeps as much as VDD level, the speed for start-up from stand-by mode is faster than the start-up by power-on. 2-(3) VOUT is internally pulled down through 5k to GND. Time constant "" of transient response (turn-off speed) of VOUT can be calculated as follows: (5[k] ROUT) x COUT (ROUT: Output load resistance) 2-(4) Load current should be OFF synchronously with this IC if the load is electronic or connected between VIN and VOUT. If some charge is continuously flown to the Output VOUT at the "OFF" state, the voltage level of VOUT will rise and could be beyond 0V And if the voltage will be +0.3V (that is designated as absolute maximum rating.), . this IC might be break down. 3) Ripple Voltage Ripple voltage of Output waveform can be roughly calculated as follows: Vripple [mVp-p] 0.5x (IOUT [mA] + Supply Current at no load [mA]) / (Oscillator Frequency: 280000 [Hz]) / COUT [F] Supply Current at no load [mA] Supply Current 1 [mA]
12
R1250Vxx1A
4)
Power Consumption Power Consumption at large load current of this IC can be calculated as follows: Wchip [mW] (VIN[V]-| Set Output Voltage |) x (IOUT[mA])
TECHNICAL NOTES
To use this IC, the following things should be considered. 1) 2) 3) 4) 5) 6) Short Protection function for each pin is not included in this IC. Use capacitors with low equivalent series resistor (ESR) for CIN, CP, COUT pins. Capacitors with large ESR make this IC's performance worse. Make wiring of GND, VIN, CP+, CP- secure enough and decrease impedance. High impedance could be a cause of unstable operation of this IC. When this IC is used with large load current, consider its radiation of heat. Basically, Vref pin can be used for soldering to the mount pad of PCB. Do not make it wiring. Load type is electronic or setting between VIN and VOUT, in cases of OFF-state of this IC and start-up state of this IC, make sure not to raise VOUT level on positive voltage side. If the voltage level is beyond +0.3V which is desig, nated as the absolute maximum rating, this IC could be broken.
13

▲Up To Search▲

Price & Availability of R1250V301A

	To Download R1250V301A Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .