Texas Instruments TPS60123PWPR, TPS60123PWP, TPS60122PWPR, TPS60121PWPR, TPS60122PWP Datasheet

TPS60120, TPS60121, TPS60122, TPS60123 REGULATED 3.3 V, 200-mA HIGH EFFICIENCY CHARGE PUMP DC/DC CONVERTERS

SLVS257A ± NOVEMBER 1999 ± REVISED DECEMBER 1999

features

DHigh Average Efficiency Over Input Voltage Range Because of Special Switching Topology

DUp to 200-mA Output Current (TPS60120 and TPS60121) From an Input Voltage Range of 1.8-V to 3.6-V

DNo Inductors Required, Low EMI

DRegulated 3.3-V ± 4% Output

DOnly Four External Components Required

D55- A Quiescent Supply Current

D0.05- A Shutdown Current

DLoad Disconnected in Shutdown

DSpace-saving, Thermally-Enhanced PowerPADt Package

DEvaluation Module Available

(TPS60120EVM-142)

´

description

The TPS6012x step-up, regulated charge pumps generate a 3.3-V ±4% output voltage from a 1.8-V to 3.6-V input voltage (two alkaline, NiCd, or NiMH batteries). The output current is 200 mA for the TPS60120/TPS60121 and 100 mA for the TPS60122/TPS60123, all from a 2-V input. Four external capacitors are needed to build a complete high efficiency dc/dc charge pump converter. To achieve the high efficiency over a wide input voltage range, the charge pump automatically selects between a 1.5x or doubler conversion mode. From a 2-V input, all ICs can start with full load current.

The devices feature the power-saving pulse-skip mode to extend battery life at light loads. TPS60120 and TPS60122 include a low battery comparator. TPS60121 and TPS60123 feature a power-good output. The logic shutdown function reduces the supply current to a maximum of 1 A and disconnects the load from the input. Special current-control circuitry prevents excessive current from being drawn from the battery during start-up. This dc/dc converter requires no inductors, therefore EMI is of low concern. It is available in the small, thermally enhanced 20-pin PowerPADt package (PWP).

applications

DBattery-Powered Applications

DTwo Battery Cells to 3.3-V Conversion

DPortable Instruments

DBattery-Powered Microprocessor Systems

DMiniature Equipment

DBackup-Battery Boost Converters

DPDA's, Organizers, Laptops

DMP-3 Portable Audio Players

DHandheld Instrumentation

DMedical Instruments (e.g., Glucose Meters)

DCordless Phones

efficiency (TPS60120, TPS60121)
	100	IO = 66 mA
	90							VO = 3.3 V
								TC = 25°C
	80
%	70	IO = 116 mA				IO = 164 mA
±	60
Efficiency
	50			IO = 216 mA
	40
	30
	20
	10
	0	2	2.2	2.4	2.6	2.8	3	3.2	3.4	3.6
	1.8
				VI ± Input Voltage ± V

typical operating circuit

	Input		TPS60120		Output
	1.8 V to 3.6 V				3.3 V, 200 mA
			IN	OUT
	Ci	R1	IN	OUT	CO
	10 F				22		F
			LBI	FB
		R2			R3
				LBO
		C1	C1+	C2+
					C2
		2.2 F	C1±	C2±
					2.2 F
			ENABLE
		OFF/ON	PGND GND

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

PowerPAD is a trademark of Texas Instruments Incorporated.

PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters.

Copyright 1999, Texas Instruments Incorporated

POST OFFICE BOX 655303 •DALLAS, TEXAS 75265

1

TPS60120, TPS60121, TPS60122, TPS60123

REGULATED 3.3 V, 200-mA HIGH EFFICIENCY CHARGE PUMP

DC/DC CONVERTERS

SLVS257A ± NOVEMBER 1999 ± REVISED DECEMBER 1999

			PWP PACKAGE									PWP PACKAGE
			(TPS60120/TPS60122)									(TPS60121/TPS60123)
				(TOP VIEW)									(TOP VIEW)
GND									GND
			1	20				GND				1	20				GND
GND			2	19				GND	GND			2	19				GND
ENABLE			3		18			LBI	ENABLE			3		18			NC
FB			4		17			LBO	FB			4		17			PG
OUT			5		16			OUT	OUT			5		16			OUT
C1+			6		15			C2+	C1+			6		15			C2+
IN			7		14			IN	IN			7		14			IN
C1±			8		13			C2±	C1±			8		13			C2±
PGND			9					PGND	PGND			9					PGND
				12									12
PGND			10	11				PGND	PGND			10	11				PGND

Thermal Pad

AVAILABLE OPTIONS

	T	PART NUMBER²		PACKAGE	DEVICE FEATURES
	A
		TPS60120PWP			2-Cell to 3.3 V, 200 mA	Low battery detector
	±40°C to 85°C	TPS60121PWP	PWP	20-Pin thermally		Power good detector
		TPS60122PWP		enhanced TSSOP	2-Cell to 3.3 V, 100 mA	Low battery detector
		TPS60123PWP				Power good detector

²The PWP package is available taped and reeled. Add R suffix to device type (e.g. TPS60120PWPR) to order quantities of 2000 devices per reel.

2	POST OFFICE BOX 655303 •DALLAS, TEXAS 75265

TPS60120, TPS60121, TPS60122, TPS60123

REGULATED 3.3 V, 200-mA HIGH EFFICIENCY CHARGE PUMP

DC/DC CONVERTERS

SLVS257A ± NOVEMBER 1999 ± REVISED DECEMBER 1999

functional block diagram

TPS60120/TPS60122

			IN
	Oscillator		C1+
			C1F
			C1±
	ENABLE		OUT
		Charge Pump	PGND
	Control	Power Stages	IN
			C2+
	Circuit
			C2F
	_
			C2±
	+
			OUT
	VREF	+	PGND
		±	FB

Shutdown/

_

_

Start-Up

LBI

Control

+

+

+

0.8 VI

+

±

VREF ±

GND

LBO

TPS60121/TPS60123
		IN
Oscillator		C1+
		C1F
		C1±
		OUT
ENABLE	Charge Pump	PGND
Control	Power Stages	IN
		C2+
Circuit
		C2F
_		C2±
+		OUT
VREF	+	PGND
	±	FB

Shutdown/

_

_

Start-Up Control

+

+

+

+

0.8 VI

VREF ±

±

GND

PG

POST OFFICE BOX 655303 •DALLAS, TEXAS 75265

3

TPS60120, TPS60121, TPS60122, TPS60123

REGULATED 3.3 V, 200-mA HIGH EFFICIENCY CHARGE PUMP

DC/DC CONVERTERS

SLVS257A ± NOVEMBER 1999 ± REVISED DECEMBER 1999

				Terminal Functions
	TERMINAL		I/O	DESCRIPTION
	NAME	NO.
	C1+	6		Positive terminal of the flying capacitor C1
	C1±	8		Negative terminal of the flying capacitor C1
	C2+	15		Positive terminal of the flying capacitor C2
	C2±	13		Negative terminal of the flying capacitor C2
				ENABLE input. Connect ENABLE to IN for normal operation. When ENABLE is a logic low, the device turns off and
	ENABLE	3	I	the supply current decreases to 0.05 µA. The output is disconnected from the input when the device is placed in
				shutdown.
	FB	4	I	Feedback input. Connect FB to OUT as close to the load as possible to achieve best regulation. Resistive divider
				is on the chip to match the internal reference voltage of 1.21 V.
	GND	1, 2,		Ground. Analog ground for internal reference and control circuitry. Connect to PGND through a short trace.
		19, 20
	IN	7,14	I	Supply input. Connect to an input supply in the 1.8-V to 3.6-V range. Bypass IN to PGND with a (CO/2) µF capacitor.
				Connect both IN through a short trace.
	LBO/PG	17	O	Low battery detector output or power good output. Open drain output of the low battery or power-good comparator.
				It can sink 1 mA. A 100-kΩ to 1-MΩ pullup is recommended. Leave terminal unconnected if not used.
				Low battery detector input (TPS60120/TPS60122 only). The input is compared to the internal 1.21-V reference
	LBI/NC	18	I	voltage. Connect terminal to ground if the low-battery detector function is not used. On the TPS60121 and
				TPS60123, this terminal is not connected.
	OUT	5, 16	O	Regulated 3.3-V power output. Connect both OUT terminals through a short trace and bypass OUT to GND with
				the output filter capacitor CO.
	PGND	9±12		Power ground. Charge-pump current flows through this pin. Connect all PGND pins together.

detailed description

operating principle

The TPS6012x charge pumps provide a regulated 3.3-V output from a 1.8-V to 3.6-V input. They deliver a maximum load current of 200 mA or 100 mA, respectively. Designed specifically for space-critical, batterypowered applications, the complete charge pump circuit requires only four external capacitors. The circuit is optimized for efficiency over a wide input voltage range.

The TPS6012x charge pumps consist of an oscillator, a 1.21-V bandgap reference, an internal resistive feedback circuit, an error amplifier, high current MOSFET switches, a shutdown/start-up circuit, a low-battery or power-good comparator, and a control circuit (see the functional block diagram).

The device consists of two single-ended charge pumps. The power stages of the charge pump are automatically configured to amplify the input voltage with a conversion factor of 1.5 or 2. The conversion ratio depends on input voltage and output current. With input voltages lower than approximately 2.4 V, the convertor will run in a voltage doubler mode with a gain of two. With a higher input voltage, the converter operates with a gain of 1.5 V. This assures high efficiency over the wide input voltage range of a two-cell battery stack and is further described in the adaptive mode switching section.

adaptive mode switching

The ON-resistance of the MOSFETs that are in the charge path of the flying capacitors is regulated when the charge pump operates in voltage doubler-mode. It is changed depending on the output voltage that is fed back into the control loop. This way, the time-constant during the charging phase can be modified and increased versus a time-constant for fully switched-on MOSFETs. The ON-resistance of both switches and the capacitance of the flying capacitor define the time constant. The MOSFET switches in the discharge path of the

charge pump are always fully switched on to their minimum rDS(on). With the time-constant during charge phase being larger than the time constant in discharge phase, the voltage on the flying capacitors stabilizes to the

lowest possible value necessary to get a stable VO.

4	POST OFFICE BOX 655303 •DALLAS, TEXAS 75265

TPS60120, TPS60121, TPS60122, TPS60123

REGULATED 3.3 V, 200-mA HIGH EFFICIENCY CHARGE PUMP

DC/DC CONVERTERS

SLVS257A ± NOVEMBER 1999 ± REVISED DECEMBER 1999

adaptive mode switching (continued)

The voltage on the flying capacitors is measured and compared with the supply voltage VI. If the voltage across the flying capacitors is smaller than half of the supply voltage, then the charge pump switches into the 1.5x conversion-mode. The charge pump switches back from a 1.5x conversion-mode to a voltage doubler mode if the load current in 1.5x conversion-mode can no more be delivered.

With this control mode the device runs in doubler-mode at low VI and in 1.5x conversion-mode at high VI to optimize the efficiency. The most desirable doubler mode is automatically selected depending on both VI and IL. This means that at light loads the device selects the 1.5x conversion-mode already at smaller supply voltages than at heavy loads.

The TPS60120 output voltage is regulated using the ACTIVE-CYCLE regulation. An active cycle controlled Charge pump utilizes two methods to control the output voltage. At high load currents it varies the on resistances of the internal switches and keeps the ratio ON/OFF time (=frequency) constant. That means the charge pump runs at a fixed frequency. It also keeps the output voltage ripple as low as in linear-mode. At light loads the internal resistance and also the amount of energy transferred per pulse is fixed and the charge pump regulates the voltage by means of a variable ratio of ON-to-OFF time. In this operating point, it runs like a skip mode controlled charge pump with a very high internal resistance, which also enables a low ripple in this operation mode. Since the charge pump does effectively switch at lower frequencies at light loads, it achieves a low quiescent current.

pulse-skip mode

In pulse-skip mode the error amplifier disables switching of the power stages when it detects an output higher than 3.3 V. The oscillator halts and the IC then skips switching cycles until the output voltage drops below 3.3 V. Then the error amplifier reactivates the oscillator and starts switching the power stages again. The pulse-skip regulation mode minimizes operating current because it does not switch continuously and deactivates all functions except bandgap reference, error amplifier, and low-battery/power-good comparator when the output is higher than 3.3 V. When switching is disabled from the error amplifier, the load is also isolated from the input. In pulse-skip mode, a special current control circuitry limits the peak current. This assures moderate output voltage ripple and also prevents the device from drawing excessive current spikes out of the battery.

start-up procedure

During start-up, i.e., when ENABLE is set from logic low to logic high, the output capacitor is charged up with a limited current until the output voltage VO reaches 0.8 ×VI. When the start-up comparator detects this voltage limit, the IC begins switching. This start-up charging of the output capacitor ensures a short start-up time and eliminates the need of a Schottky diode between IN and OUT. The IC starts with a maximum load, which is defined by a 16-Ω resistor or 33-Ω resistor, respectively.

shutdown

Driving ENABLE low places the device in shutdown mode. This disables all switches, the oscillator, and control logic. The device typically draws 0.05 µA (1 µA max) of supply current in this mode. Leakage current drawn from the output is as low as 1 µA max. The device exits shutdown once ENABLE is set to a high level. The typical no-load shutdown exit time is 10 µs. When the device is in shutdown, the load is isolated from the input.

undervoltage lockout

The TPS6012x devices have an undervoltage lockout feature that deactivates the device and places it in shutdown mode when the input voltage falls below 1.6 V.

low-battery detector (TPS60120 and TPS60122)

The internal low-battery comparator trips at 1.21 V ± 5% when the voltage on LBI ramps down. The battery voltage at which the comparator initiates a low battery warning at the LBO output can easily be programmed with a resistive divider as shown in Figure 1. The sum of resistors R1 and R2 is recommended to be in the 100 kΩ to 1 MΩ range.

POST OFFICE BOX 655303 •DALLAS, TEXAS 75265

5

TPS60120, TPS60121, TPS60122, TPS60123

REGULATED 3.3 V, 200-mA HIGH EFFICIENCY CHARGE PUMP

DC/DC CONVERTERS

SLVS257A ± NOVEMBER 1999 ± REVISED DECEMBER 1999

low-battery detector (TPS60120 and TPS60122) (continued)

LBO is an open drain output. An external pullup resistor to OUT, in the 100 kΩ to 1 MΩ range, is recommended. During start-up, the LBO output signal is invalid for the first 500 µs. LBO is high impedance when the device is disabled.

If the low-battery comparator function is not used, connect LBI to ground and leave LBO unconnected.

VO

IN

VBAT

R3

			R1
LBO	_	LBI	V(TRIP) +	1.21 V 1 ) R1
				R2
	+		R2
	VREF	+
		±

Figure 1. Programming of the Low-Battery Comparator Trip Voltage

Formulas to calculate the resistive divider for low battery detection, with VLBI = 1.15 V ± 1.27 V:

R2 + 1 MW VLBI

VBat

R1 + 1 MW * R2

Formulas to calculate the minimum and maximum battery voltage that triggers the low battery detector:

VBat(min) + VLBI(min)		R1(min) ) R2(max)
				R2(max)
VBat(max) + VLBI(max)		R1(max) ) R2(min)
				R2(min)
Table 1. Recommended Values for the Resistive Divider From the E96 Series (±1%),
				VLBI = 1.15 V ± 1.27 V
VBAT/V	R1/kΩ			R2/kΩ			VBAT (MIN)/V			VBAT(MAX)/V
1.8	357			732			1.700		±5.66%	1.902		5.67%
1.9	365			634			1.799		±5.32%	2.016		6.11%
2.0	412			634			1.883		±5.86%	2.112		5.6%
2.1	432			590			1.975		±5.95%	2.219		5.67%
2.2	442			536			2.080		±5.45%	2.338		6.27%

Using ±1% accurate resistors, the total accuracy of the trip voltage is about ±6%, considering the ±4% accuracy the integrated voltage reference adds and considering that not every calculated resistor value is available.

A 100 nF bypass capacitor should be connected in parallel to R2 if large line transients are expected. These voltage drops can inadvertently trigger the low-battery comparator and produce a wrong low-battery warning signal at the LBO terminal.

6	POST OFFICE BOX 655303 •DALLAS, TEXAS 75265

TPS60120, TPS60121, TPS60122, TPS60123

REGULATED 3.3 V, 200-mA HIGH EFFICIENCY CHARGE PUMP

DC/DC CONVERTERS

SLVS257A ± NOVEMBER 1999 ± REVISED DECEMBER 1999

power-good detector (TPS60121 and TPS60123)

The PG terminal is an open-drain output that is pulled low when the output is out of regulation. When the output voltage rises to about 90% of its nominal voltage, the power-good output is released. PG is high impedance when the device is disabled. A pullup resistor must be connected between PG and OUT. The pullup resistor should be in the 100 kΩ to 1 MΩ range. If the power-good function is not used, then PG should remain unconnected.

TPS60121

Input

IN

OUT

Output

1.8 V to 3.6 V

3.3 V, 200 mA

CI

IN

OUT

CO

10 µF

22 µF

NC

FB

R1

PG

1 MΩ

Power-Good Output

C1

C1+

C2+

C2

C1±

2.2 µF

C2±

2.2 µF

ENABLE

Off/On

PGND GND

Figure 2. Typical Operating Circuit Using Power-Good Comparator

absolute maximum ratings (see Note 1)²

Input voltage range, VI (IN, OUT, ENABLE, FB, LBI, LBO/PG) . . . . . . . . . . . . . . . . . . . . . . . . . . . ±0.3 V to 5.5 V

Differential input voltage, VID (C1+, C2+ to GND) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±0.3 V to (VO + 0.3 V) Differential input voltage, VID (C1±, C2± to GND) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±0.3 V to (VI + 0.3 V) Continuous total power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . See dissipation rating table

Continuous output current TPS60120, TPS60121 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300 mA Continuous output current TPS60122, TPS60123 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150 mA

Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±55°C to 150°C Lead temperature 1,6 mm (1/16 inch) from case for 10s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260°C

Maximum junction temperature, TJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150°C

²Stresses beyond those listed under ªabsolute maximum ratingsº may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under ªrecommended operating conditionsº is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

NOTE 1: V(ENABLE),V(LBI)andV(LBO/PG)canexceedVIuptothemaximumratedvoltagewithoutincreasingtheleakagecurrentdrawnbythese

inputs.

DISSIPATION RATING TABLE 1 FREE-AIR TEMPERATURE (see Figure 3)

	PACKAGE	TA ≤ 25_C	DERATING FACTOR	TA = 70_C	TA = 85_C
		POWER RATING	ABOVE TA = 25_C	POWER RATING	POWER RATING
	PWP	700 mW	5.6 mW/_C	448 mW	364 mW
		DISSIPATION RATING TABLE 2 FREE-AIR TEMPERATURE (see Figure 4)
	PACKAGE	TC ≤ 62.5_C	DERATING FACTOR	TC = 70_C	TC = 85_C
		POWER RATING	ABOVE TC = 62.5_C	POWER RATING	POWER RATING
	PWP	25 mW	285.7 mW/_C	22.9 mW	18.5 mW

POST OFFICE BOX 655303 •DALLAS, TEXAS 75265

7