ADP3605 Fast Delivery |IC PHOENIX CO.,LIMITED

ADP3605 ,120 mA Switched Capacitor Voltage Inverter with Regulated OutputSpecifications subject to change without notice.1ABSOLUTE MAXIMUM RATINGS Storage Temperature Range ..
ADP3605 ,120 mA Switched Capacitor Voltage Inverter with Regulated OutputGENERAL DESCRIPTIONV V –3.0VThe ADP3605 is a 120 mA regulated output switched capacitor VIN INOUT+* ..
ADP3605AR ,120 mA Switched Capacitor Voltage Inverter with Regulated OutputSpecifications subject to change without notice.1ABSOLUTE MAXIMUM RATINGS Storage Temperature Range ..
ADP3605AR-3 ,120 mA Switched Capacitor Voltage Inverter with Regulated OutputSPECIFICATIONSIN A P OParameter Symbol Conditions Min Typ Max UnitsOPERATING SUPPLY RANGE V 35 6 VS ..
ADP3605ARU-3 ,120 mA Switched Capacitor Voltage Inverter with Regulated OutputGENERAL DESCRIPTIONV V –3.0VThe ADP3605 is a 120 mA regulated output switched capacitor VIN INOUT+* ..
ADP3607 ,50 mA Switched Capacitor Voltage Boost with Regulated OutputSpecifications subject to change without notice.1ABSOLUTE MAXIMUM RATINGSORDERING GUIDE(T = +25

ADP3605
120 mA Switched Capacitor Voltage Inverter with Regulated Output
REV.A
120 mA Switched Capacitor
Voltage Inverter with Regulated Output
FUNCTIONAL BLOCK DIAGRAM
–3.0VVIN
*CIN
4.7mF*CP
4.7mF
OFFON
*FOR BEST PERFORMANCE, 10mF IS RECOMMENDED
CP : SPRAGUE, 293D475X0010B2W
CIN, CO: TOKIN, 1E475ZY5UC205F
Figure 1.Typical Application Circuit
FEATURES
Fully Regulated Output Voltage (–3 V and Adjustable)
High Output Current: 120 mA
Output Accuracy: 63%
250 kHz Switching Frequency
Low Shutdown Current: 2 mA Typical
Input Voltage Range from 3 V to 6 V
SO-8 and RU-14 Packages
–408C to +858C Ambient Temperature Range
APPLICATIONS
Voltage Inverters
Voltage Regulators
Computer Peripherals and Add-On Cards
Portable Instruments
Battery Powered Devices
Pagers and Radio Control Receivers
Disk Drives
Mobile Phones
GENERAL DESCRIPTION
The ADP3605 is a 120 mA regulated output switched capacitor
voltage inverter. It provides a regulated output voltage with
minimum voltage loss and requires a minimum number of ex-
ternal components. In addition, the ADP3605 does not require
the use of an inductor.
Pin-for-pin and functionally compatible with the ADP3604, the
internal oscillator of the ADP3605 runs at 500 kHz nominal
frequency which produces an output switching frequency of
250 kHz. This allows for the use of smaller charge pump and
filter capacitors.
The ADP3605 provides an accuracy of –3% with a typical shut-
down current of 2 mA. It can also operate from a single positive
input voltage as low as 3 V. The ADP3605 is offered with the
regulation fixed at –3 V or adjustable via external resistors over
a –3 V to –6 V range.
ADP3605–SPECIFICATIONS1, 2, 3
NOTESCapacitors CIN, CO and CP in the test circuit are 4.7 mF with 0.1 W ESR.See Figure 1 Conditions.All limits at temperature extremes are guaranteed via correlation using standard Statistical Quality Control (SQC) methods.For the adjustable device, a 1% resistor should be used to maintain output voltage tolerance. For both device types, tolerances can be improved by >1% using larger
value and lower ESR capacitors for CO and CP.
Specifications subject to change without notice.
ABSOLUTE MAXIMUM RATINGS1
(TA = +25°C unless otherwise noted)
Input Voltage (V+ to GND, GND to OUT) . . . . . . . .+7.5 V
Input Voltage (V+ to OUT) . . . . . . . . . . . . . . . . . . . . .+11 V
Output Short Circuit Protection . . . . . . . . . . . . . . . . . . .1 sec
Power Dissipation, SO-8 . . . . . . . . . . . . . . . . . . . . . .660 mWJA2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .150°C/W
Power Dissipation, RU-14 . . . . . . . . . . . . . . . . . . . . .600 mWJA2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .165°C/W
Operating Temperature Range . . . . . . . . . . .–40°C to +85°C
Storage Temperature Range . . . . . . . . . . . .–65°C to +150°C
Lead Temperature Range (Soldering 10 sec) . . . . . . . .+300°C
Vapor Phase (60 sec) . . . . . . . . . . . . . . . . . . . . . . . .+215°C
Infrared (15 sec) . . . . . . . . . . . . . . . . . . . . . . . . . . .+220°C
NOTESThis is a stress rating only; operation beyond these limits can cause the device to
be permanently damaged.qJA is specified for worst case conditions with device soldered on a circuit board.
ORDERING GUIDE
*Contact the factory for the availability of other output voltage options.
(VIN = 5.0 V @ TA = +258C, CP = CO = 4.7 mF unless otherwise noted)
CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000V readily
accumulate on the human body and test equipment and can discharge without detection.
Although the ADP3605 features proprietary ESD protection circuitry, permanent damage may
occur on devices subjected to high energy electrostatic discharges larger than 600V HBM.
Therefore, proper ESD precautions are recommended to avoid performance degradation or loss
of functionality.
Table I.Other Members of ADP36xx Family1
NOTESSee individual data sheets for detailed ordering information.SO = Small Outline; TSSOP = Thin Shrink Small Outline Package.
Table II.Alternative Capacitor Technologies
NOTERefer to capacitor manufacturer's data sheet for operation below 0°C.
Table III.Recommended Capacitor Manufacturers
PIN FUNCTION DESCRIPTIONS
PIN CONFIGURATIONS
RU-14SO-8
NC = NO CONNECT
CP+
GND
CP–
VIN
VOUT
VSENSESD
ADP3605
SUPPLY VOLTAGE – Volts
OSCILLATOR FREQUENCY – kHz
25033.5644.555.5
Figure 2.Oscillator Frequency vs.
Supply Voltage
TEMPERATURE – 8C
OSCILLATOR FREQUENCY – kHz
220
Figure 5.Oscillator Frequency vs.
Temperature
SUPPLY VOLTAGE – Volts
SUPPLY CURRENT – mA
IN NORMAL MODE
SUPPLY CURRENT –
IN SHUTDOWN MODE
Figure 8.Supply Current vs. Supply
Voltage
–Typical Performance Characteristics
SUPPLY CURRENT – mA
IN NORMAL MODE
TEMPERATURE – 8C
SUPPLY CURRENT –
IN SHUTDOWN MODE
0.5
Figure 3.Supply Current vs.
Temperature
LOAD CURRENT – mA
INPUT CURRENT – mA
100
Figure 6.Average Input Current
vs. Output Current
Figure 9 .Start-Up Under Full Load
TEMPERATURE – 8C
OUTPUT VOLTAGE – Volts
–2.98
Figure 4.Output Voltage vs.
Temperature
LOAD CURRENT – mA
OUTPUT VOLTAGE – Volts
240280
Figure 7.Output Voltage vs. Load
Current
Figure 10.Enable/Disable Time
Under Full Load
THEORY OF OPERATION
The ADP3605 uses a switched capacitor principle to generate a
negative voltage from a positive input voltage. An onboard
oscillator generates a two phase clock to control a switching
network that transfers charge between the storage capacitors.
The switches turn on and off at a 250 kHz rate, which is gener-
ated from an internal 500 kHz oscillator. The basic principle
behind the voltage inversion scheme is illustrated in Figures 11
and 12.VIN
VOUT
Figure 11. ADP3605 Switch Configuration Charging the
Pump Capacitor
During phase one, S1 and S2 are ON, charging the pump ca-
pacitor to the input voltage. Before the next phase begins, S1
and S2 are turned OFF as well as S3 and S4 to prevent any
overlap. S3 and S4 are turned ON during the second phase (see
Figure 12) and charge stored in the pump capacitor is trans-
ferred to the output capacitor.S2S3
VIN
VOUT
Figure 12.ADP3605 Switch Configuration Charging the
Output Capacitor
During the second phase, the positive terminal of the pump
capacitor is connected to ground through variable resistance
switch, S3, and the negative terminal is connected to the out-
put, resulting in a voltage inversion at the output terminal.
The ADP3605 block diagram is shown on the front page.
APPLICATION INFORMATION
Capacitor Selection
The ADP3605’s high internal oscillator frequency permits the
use of small capacitors for both the pump and the output ca-
pacitors. For a given load current, factors affecting the output
voltage performance are:
• Pump (CP) and output (CO) capacitance.
• ESR of the CP and CO.
When selecting the capacitors, keep in mind that not all manu-
facturers guarantee capacitor ESR in the range required by the
circuit. In general, the capacitor’s ESR is inversely proportional
to its physical size, so larger capacitance values and higher volt-
age ratings tend to reduce ESR. Since the ESR is also a function
of the operating frequency, when selecting a capacitor, make
sure its value is rated at the circuit's operating frequency.
Temperature is another factor affecting capacitor performance.
Figure 13 illustrates the temperature effect on various capaci-
tors. If the circuit has to operate at temperatures significantly
different from 25°C, the capacitance and ESR values must be
carefully selected to adequately compensate for the change.
Various capacitor technologies offer improved performance over
temperature; for example, certain tantalum capacitors provide
good low-temperature ESR but at a higher cost. Table II pro-
vides the ratings for different types of capacitor technologies to
help the designer select the right capacitors for the applica-
tion. The exact values of CIN and CO are not critical. How-
ever, low ESR capacitors such as solid tantalum and multilayer
ceramic capacitors are recommended to minimize voltage loss at
high currents. Table III shows a partial list of the recommended
low ESR capacitor manufacturers.
Input Capacitor
A small 1 mF input bypass capacitor, preferably with low ESR,
such as tantalum or multilayer ceramic, is recommended to
reduce noise and supply transients and supply part of the peak
input current drawn by the ADP3605. A large capacitor is rec-
ommended if the input supply is connected to the ADP3605
through long leads, or if the pulse current drawn by the device
might affect other circuitry through supply coupling.
Output Capacitor
The output capacitor (CO) is alternately charged to the CP volt-
age when CP is switched in parallel with CO. The ESR of CO
introduces steps in the VOUT waveform whenever the charge
pump charges CO, which contributes to VOUT ripple. Thus,
ceramic or tantalum capacitors are recommended for CO to
minimize ripple on the output. Figure 14 illustrates the output
ripple voltage effect for various capacitance and ESR values.
Note that as the capacitor value increases beyond the point
where the dominant contribution to the output ripple is due to
the ESR, no significant reduction in VOUT ripple is achieved by
added capacitance. Since output current is supplied solely by
the output capacitor, CO, during one-half of the charge-pump
cycle, peak-to-peak output ripple voltage is calculated by using
the following formula.
where:IL = Load Current
FS = 250 kHz nominal switching frequency
CO = 10 mF with an ESR of 0.15 W
Multiple smaller capacitors can be connected in parallel to yield
lower ESR and lower cost. For lighter loads, proportionally
smaller capacitors are required. To reduce high frequency
noise, bypass the output with a 0.1 mF ceramic capacitor in
parallel with the output capacitor.
ADP3605
Pump Capacitor
The ADP3605 alternately charges CP to the input voltage when
CP is switched in parallel with the input supply, and then trans-
fers charge to CO when CP is switched in parallel with CO.
During the time CP is charging, the peak current is approxi-
mately two times the output current.
During the time CP is delivering charge to CO, the supply cur-
rent drops down to about 3 mA.
A low ESR capacitor has much greater impact on performance
for CP than CO since current through CP is twice the CO cur-
rent. Therefore, the voltage drop due to CP is about four times
the ESR of CP times the load current. While the ESR of CO
affects the output ripple voltage, the voltage drop generated by
the ESR of CP, combined with the voltage drop due to the output
source resistance, determines the maximum available VOUT.
TEMPERATURE – 8C
ESR –
0.1
Figure 13.ESR vs. Temperature
CAPACITANCE – mF
OUTPUT RIPPLE – mV6080100120140
Figure 14.Output Ripple Voltage (mV) vs. Capacitance
and ESR
Improved Load Regulation
In most applications, the IR drop from printed circuit board
traces is not critical. VSENSE should be connected to the output
at a convenient PCB location close to the load. However, if a
reduction in IR drop or improvement in load regulation is de-
sired, the sense line can be used to monitor the output voltage
at the load. To avoid excessive noise pickup, keep the VSENSE
line as short as possible and away from any noisy line.
Shutdown Mode
The ADP3605’s output can be disabled by pulling the SD pin
(Pin 4) high to a TTL/CMOS logic compatible level which will
stop the internal oscillator. In shutdown mode, the quiescent
current is reduced to 2 mA (typical). Applying a digital low level
or tying the SD Pin to ground will turn on the output. If the
shutdown feature is not used, Pin 4 should be tied to the
ground pin.
Power Dissipation
The power dissipation of the ADP3605 circuit must be limited
such that the junction temperature of the device does not exceed
the maximum junction temperature rating. Total power dissipa-
tion is calculated as follows:
P = (VIN –|VOUT|) IOUT + (VIN) IS
Where IOUT and IS are output current and supply current, VIN
and VOUT are input and output voltages respectively.
For example: assuming worst case conditions, VIN = 6 V,
VOUT = –2.9 V, IOUT = 120 mA and IS = 5 mA. Calculated
device power dissipation is:
P » (6 V–|–2.9 V|)(0.12) + (6 V)(0.005 A) = 402 mW
This is far below the 660 mW power dissipation capability of the
ADP3605 in SO-8 or 600 mW in RU-14
General Board Layout Guidelines
Since the ADP3605’s internal switches turn on and off very fast,
good PC board layout practices are critical to ensure optimal
operation of the device. Improper layouts will result in poor load
regulation, especially under heavy loads. Following these simple
layout guidelines will improve output performance.Use adequate ground and power traces or planes.Use single point ground for device ground and input and
output capacitor grounds.Keep external components as close to the device as possible.Use short traces from the input and output capacitors
to the input and output pins respectively.

Partno	Mfg	Dc	Qty	Available	Descript
ADP3605		N/a	2400	avai	120 mA Switched Capacitor Voltage Inverter with Regulated Output
ADP3605	n/a	N/a	2400	avai	120 mA Switched Capacitor Voltage Inverter with Regulated Output