Freescale 34674 Advance Information

Freescale Semiconductor

Advance Information

High Input Voltage Travel Charger for Single-cell Li-Ion Batteries

Document Number: MC34674

Rev. 1.0, 01/2008

34674

The MC34674 is a fully integrated single-cell Li-Ion and Li-Polymer
battery charger optimized for travel charger applications. The few
external components required include a dual-color LED for charge­status indication, a negative temperature coefficient (NTC) thermistor
circuit for setting the charge temperature window, and two decoupling
capacitors. The high input voltage, up to 28V, allows low-cost ac/dc
converters to be used for further system cost reduction. A typical
charge cycle of the MC34674 includes trickle, constant-current (CC)
and constant-voltage (CV) charge modes. The CC-mode current is
selectable from 50mA to 1.05A with 8% accuracy and the constant­output voltage in the CV-mode is fixed at 4.2V with 0.4% accuracy over

-20°C to 70°C temperature range.

The MC34674 has all the features such as trickle charging for a
deeply discharged battery, an internal timer for termination to prevent
charging a failed battery, charger current thermal foldback for thermal
protection, and smart battery connection verification to prevent
charging in case there is no battery connected. It also protects the
system with its input over-voltage protection (OVP) feature. In addition,
it has a 2.6V falling power-on-reset (POR) threshold, making it perfect
to work with current limited power supplies. When the charger is
disabled, the BAT pin leaks less than 1

µA current from the battery. All

the above functions are fit into a small 8-lead 2X3 UDFN package.

Features

• No external MOSFET, reverse-blocking diode or current-

• Driving a dual-color LED and smart battery connection

sense resistor are required

• 28V maximum input voltage rating with 11V over-voltage

protection threshold

• Factory programmable charge current

• Trickle charge for fully discharged batteries

• Interface to NTC thermistor

• Internal timer and thermal current limit

• Small 2X3 mm2 thermally enhanced UDFN package

• Pb-free packaging designated by suffix code EP

• ±0.4% voltage accuracy over -20°C to 70°C

POWER MANAGEMENT IC

EP SUFFIX (PB-FREE)

98ASA10774D

8-PIN UDFN

ORDERING INFORMATION

Device

MC34674AEP/R2 -40°C to 85°C 8-UDFN

Temperature

Range (T

)

A

Package

verification optimized for travel charger applications

V

IN

C

IN

OFF

ON

VIN

RED

GRN
EN

34674

BAT

VREF

TEMP

GND

Figure 1. 34674 Simplified Application Diagram

* This document contains certain information on a new product.

Specifications and information herein are subject to change without notice.

© Freescale Semiconductor, Inc., 2007-8. All rights reserved.

C

R

PU

R

OUT

S

TO BATTERY

TO BATTERY NTC
(THERMISTOR)

DEVICE VARIATIONS

DEVICE VARIATIONS

Table 1. Device Variations

Freescale Part No.

MC34674A
MC34674B
MC34674C
MC34674D

Notes

1. Freescale offers a series of MC34674 variations. Each variation has an increment of 50mA or 100mA for the CC-mode current.

(1)

CC-Mode Current (ICC) Reference Location

1.05A Table 6
850mA Table 6
650mA Table 6
450mA Table 6

34674

Analog Integrated Circuit Device Data

2 Freescale Semiconductor

INTERNAL BLOCK DIAGRAM

INTERNAL BLOCK DIAGRAM

VIN

RED

GRN

EN

V

IN

Monitor

6mA

6mA

Internal
Supply

REF

VIN

+

BAT

V

–

OS

Charge

Control

+
–

Logic

Control

GND

–
+

–
+

–

+

+
–

V

REF

Die

Temp

110°C

I

REF

I

EOC

NTC

Interface

BAT

VREF
TEMP

Figure 2. 34674 Simplified Internal Block Diagram

34674

Analog Integrated Circuit Device Data
Freescale Semiconductor 3

PIN CONNECTIONS

PIN CONNECTIONS

VIN

GRN

1

2

BAT

8

VREF

7

EPAD

RED

EN

3

4

TEMP

6

GND

5

Figure 3. 34674 Pin Connections

Table 2. 34674 Pin Definitions

A functional description of each pin can be found in the Functional Pin Description section beginning on page 12.

Pin Number Pin Name Pin Function Formal Name Definition

1
2
3
4
5
6
7

8

EPAD

VIN Input Input supply
GRN Output Green indicator
RED Output Red indicator

EN Input Enable

GND Ground Ground

TEMP Input NTC interface input
VREF Output NTC interface bias

voltage

BAT Output Charger output

EPAD N/A Exposed pad

The supply input.
Indication of the charge status. Open drain output with 6mA current limit.
Indication of the charge status. Open drain output with 6mA current limit.
Active-low enable logic input.
Ground.
The NTC thermistor interface pin.
The bias voltage for the NTC interface circuit.

The charger output pin to the battery.
Exposed pad for thermal dissipation enhancement. Must be soldered on

the large ground plane on the PCB to increase the thermal dissipation.
The pad must be connected to GND electrically.

34674

Analog Integrated Circuit Device Data

4 Freescale Semiconductor

ELECTRICAL CHARACTERISTICS

MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

MAXIMUM RATINGS

Table 3. Maximum Ratings

All voltages are with respect to ground unless otherwise noted. Exceeding these ratings may cause a malfunction or

permanent damage to the device.

Ratings Symbol Value Unit

ELECTRICAL RATINGS

Input voltage range

VIN Pin
GRN and RED Pins
EN, BAT, REF and TEMP Pins

ESD Voltage

(2)

Human Body Model (HBM)
Machine Model (MM)

THERMAL RATINGS

Operating Temperature

Ambient

Junction
Storage Temperature
Thermal Resistance

(3)

Junction-to-Case

Junction-to-Ambient
Peak Package Reflow Temperature During Reflow

(4),(5)

Notes

2. ESD testing is performed in accordance with the Human Body Model (HBM) (C
(MM) (C

= 200pF, R

ZAP

ZAP

= 0Ω).

3. Device mounted on the Freescale EVB test board per JEDEC DESD51-2.

4. Pin soldering temperature limit is for 10 seconds maximum duration. Not designed for immersion soldering. Exceeding these limits may
cause malfunction or permanent damage to the device.

5. Freescale’s Package Reflow capability meets Pb-free requirements for JEDEC standard J-STD-020C. For Peak Package Reflow
Temperature and Moisture Sensitivity Levels (MSL), Go to www.freescale.com, search by part number [e.g. remove prefixes/suffixes
and enter the core ID to view all orderable parts. (i.e. MC33xxxD enter 33xxx), and review parametrics.

V

GRN

VEN, V

V

REF

V

T

ZAP

T

R

V

IN

, V

RED

,

BAT

, V

TEMP

ESD

T

A

T

J

STG

θJC

R

θJA

PPRT

= 100pF, R

-0.3 to 28

-0.3 to 12

-0.3 to 5.5

±2000

±200

-40 to 85

-40 to 150

-65 to 150
°C/W

10
70

Note 5

= 1500Ω), and the Machine Model

ZAP

V

V

°C

°C

°C

34674

Analog Integrated Circuit Device Data
Freescale Semiconductor 5

ELECTRICAL CHARACTERISTICS

STATIC ELECTRICAL CHARACTERISTICS

STATIC ELECTRICAL CHARACTERISTICS

Table 4. Static Electrical Characteristics

Characteristics noted under conditions VIN = 5.0V, -40°C ≤ TA ≤ 85°C, CIN = C
noted. Typical values noted reflect the approximate parameter means at VIN = 5.0V and TA = 25°C under nominal conditions,
unless otherwise noted.

Characteristic Symbol Min Typ Max Unit

POWER INPUT

Input Voltage Range
VIN Pin Supply Current

Charger enabled
Charger disabled

Power On Reset

Rising VIN threshold
Falling VIN threshold

(6)

(7)

V

V

I

IN

POR

IN

= 1µF (see Figure 1), unless otherwise

OUT

4.3 10 V

-

-

3.0

-

1400

300

-

2.4

-

350

3.9

2.6

µA

V

Over-Voltage Protection Rising Threshold
Over-Voltage-Protection Threshold Hysteresis
VIN-BAT Offset Voltage

V

OVP

V

OVPHYS

V

OS

Rising threshold
Falling threshold

OUTPUT

Regulated Output Voltage

VIN = 5.0V; I
VIN = 5.0V; I
VIN = 5.0V; I

= 100mA; TA = 25°C

BAT

= 100mA; TA = -20 to 70°C

BAT

= 100mA; TA = -40 to 85°C

BAT

Power MOSFET On Resistance

V

BAT

= 4.0V; I

BAT

= 0.5A; I

CHG

BAT Pin Standby Current

= 1.05A

V

R

DS(ON)

I

STDBY

BAT

VIN not powered or charger disabled
VIN powered and in charge completion state (average over 2
seconds)

(8)

CHARGE CURRENT

Constant-Current-Mode Charge Current Range
I

Accuracy

CHG

Tested at 650mA

Trickle-Mode Charge Current

(8)

(9)

(9)

End-of-Charge (EOC) Threshold

When I

is set to 650mA

CHG

(8)

I

CHG

I

CHG

I

TRKL

I

EOC

Notes

6. Refer to the Power-on-Reset parameter for VIN turn on and turn off values.

7. Supply current does not include the current delivered to the battery through the BAT pin.

8. Not tested. Guaranteed by design.

9. Tested over the temperature range -20°C ≤ TA ≤ 85°C

10 11 12 V

- 400 - mV

-

1.0

4.190

4.183

4.179

-

-

4.20

4.20

4.20

60
22

4.210

4.217

4.221

- 265 450

-

-2.0

-

-

1.0

4.0

50 - 1050 mA

92 100 108

7.0 10 13 % I

52 65 78

mV

V

mΩ

µA

%

CHG

mA

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Analog Integrated Circuit Device Data

6 Freescale Semiconductor

Table 4. Static Electrical Characteristics (continued)

Characteristics noted under conditions VIN = 5.0V, -40°C ≤ TA ≤ 85°C, CIN = C
noted. Typical values noted reflect the approximate parameter means at V
unless otherwise noted.

Characteristic Symbol Min Typ Max Unit

CHARGE THRESHOLDS

Trickle-mode Rising Threshold Voltage
Trickle-mode Threshold Voltage Hysteresis
Recharge Falling Threshold Voltage
Recharge Threshold Voltage Hysteresis

BATTERY CONNECTION VERIFICATION

Battery Connection Verification Discharge Current (Over 0.8V to

(10)

5.0V)
Output Current in Charge Completion State

(10)

Discharge Current in Charge Completion State During the 82ms

NTC INTERFACE

Low Temperature Rising Threshold
Low Temperature Falling Threshold
High Temperature Falling Threshold
High Temperature Rising Threshold

(11)

(11)

(11)

(11)

Die Thermal Limit

LOGIC INPUT AND OUTPUT

EN Input High Threshold Voltage
EN Input Low Threshold Voltage
EN Pin Internal Pull-Down Current
GRN and RED Sink Current

Pin voltage is between 0.8V and 5.0V

Open-Drain Off Leakage

Biased at 5.0V

Notes

10. Not tested. Guaranteed by design.

11. These threshold parameters are specified as a ratio of V
rises when the temperature is falling from high to low, and V

(10)

/VREF. Due to the negative-temperature-coefficient thermistor, V

TEMP

TEMP

V

TRKL

V

TRKLHYS

V

RECH

V

THRCHG

I

DCHG

I

CC

I

DCC

V

LTRT

V

LTFT

V

HTFT

V

HTRT

T

LIM

V

IH

V
I

EN

I

GRSINK

I

ODLEAK

falls when the temperature is rising from low to high.

STATIC ELECTRICAL CHARACTERISTICS

= 1µF (see Figure 1), unless otherwise

OUT

= 5.0V and TA = 25°C under nominal conditions,

IN

ELECTRICAL CHARACTERISTICS

2.8 2.9 3.0 V

- 100 - mV

4.07 4.10 4.135 V

- 25 50 mV

4.5 6.0 7.5 mA

- 24 - µA

- 585 - µA

0.6592 2/3 0.6741 VREF

- 0.6468 - VREF

0.3297 1/3 0.3389 VREF

- 0.3441 - VREF

95 110 125 °C

1.5 - - V

IL

- - 0.5 V

- 2.0 7.5 µA

5.0 6.0 7.0

- - 1.0

mA

µA

TEMP

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Analog Integrated Circuit Device Data
Freescale Semiconductor 7

ELECTRICAL CHARACTERISTICS

DYNAMIC ELECTRICAL CHARACTERISTICS

DYNAMIC ELECTRICAL CHARACTERISTICS

Table 5. Dynamic Electrical Characteristics

Characteristics noted under conditions V
noted. Typical values noted reflect the approximate parameter means at VIN = 5.0V and TA = 25°C under nominal conditions,
unless otherwise noted.

Characteristic Symbol Min Typ Max Unit

END OF CHARGE

EOC Filtering Time

OSCILLATOR

Oscillator Frequency

INTERNAL TIMER

Safety Timer for Fast Charge Mode
Safety Timer for Trickle Charge Mode

ENABLE VERIFICATION

Enable Verification Time

BATTERY CONNECTION VERIFICATION

Discharge Time in Charge Completion State
Discharge Repeating Time

Notes

12. Not tested. Guaranteed by design.

(12)

(12)

= 5.0V, -40°C ≤ TA ≤ 85°C, CIN = C

IN

(12)

t

EOC

f

OSC

t

FCM

t

TCM

t

EV

t

DCCC

t

DR

= 1µF (see Figure 1), unless otherwise

OUT

500 - 1000 ms

40.0 50.0 60.0 kHz

3.68 4.6 5.52 Hour

0.46 0.575 0.69 Hour

- 100 - ms

- 82 - ms

- 1968 - ms

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Analog Integrated Circuit Device Data

8 Freescale Semiconductor