ST L9524C User Manual

Features

■ Quad gate driver for external N-channel Power

MOSFETs in high-side configuration: – Gates driven by PWM output signal – Adjustable gate charge/discharge currents – Limited gate-to-source voltages – Negative clamping for inductive loads – Advanced run-off control – Regulation of the power through the glow

plugs

■ Control output for external relay driver

■ Battery-voltage-compatible two-wire interface

■ Supply voltage monitoring with shutdown

■ Battery voltage monitoring with shutdown

■ Junction temperature monitoring with

shutdown

■ Monitoring of currents through the glow plugs

with shutdown at overcurrent (adjustable threshold)

■ Monitoring of external switches

■ Charge pump voltage monitoring with

shutdown

■ Active clamping during load dump

Table 1. Device summary

L9524C

Glow plug system control IC

SO24

Description

The L9524C is a control IC for up to six glow plugs of diesel engines. The glow plugs are switched by up to four external PWM-controlled N-channel Power MOSFETs or a single relay in high-side configuration.

Supply voltage, battery voltage, junction temperature, switches, currents through the glow plugs, and charge pump voltage are monitored.

A two-wire interface is used to communicate with the diesel engine management system.

Order code Package Packing

L9524C SO24 Tube

L9524C-TR SO24 Tape and reel

January 2008 Rev 3 1/27

www.st.com

Contents L9524C

Contents

1 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

2 Pins description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

3 Electrical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

3.1 Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

3.2 Thermal data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

3.3 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

4 Functional description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

4.1 Operating modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

4.2 Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

4.3 Control input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

4.4 Diagnostic output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

4.5 Current monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

4.6 Switch monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

4.7 Thermal shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

4.8 Gate drivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

4.9 Relay output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

4.10 Gate charge/discharge current variation . . . . . . . . . . . . . . . . . . . . . . . . . 19

4.11 Overcurrent threshold variation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

4.12 Advanced run-off control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

4.13 Output timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

4.14 Power regulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

5 Application diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

6 Package information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

7 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

2/27

L9524C List of tables

List of tables

Table 1. Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Table 2. Pins description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Table 3. Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Table 4. Thermal data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Table 5. Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Table 6. Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Table 7. Go / no-go protocol description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Table 8. Failure register description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Table 9. Sense input pin connection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Table 10. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

3/27

List of figures L9524C

List of figures

Figure 1. Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Figure 2. Pin connection (top view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Figure 3. Shunt sense versus transistor sense . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Figure 4. Control input signal in transistor mode (modes 3 to 6) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Figure 5. Permanent switch on of glow plugs at first falling edge in transistor mode (modes 3 to 6) 14

Figure 6. Control input signal in mode 2 for permanent switch on . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Figure 7. Serial diagnostic interface protocol. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Figure 8. Timing diagram of advanced run-off control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Figure 9. Output timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Figure 10. Mode 1: relay mode, go/no-go diagnostic interface protocol . . . . . . . . . . . . . . . . . . . . . . . 22

Figure 11. Mode 2: relay mode, serial diagnostic interface protocol . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Figure 12. Mode 3: transistor mode, shunt sense, no power regulation . . . . . . . . . . . . . . . . . . . . . . . 23

Figure 13. Mode 4: transistor mode, shunt sense, power regulation . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Figure 14. Mode 5: transistor mode, transistor sense, no power regulation . . . . . . . . . . . . . . . . . . . . 24

Figure 15. Mode 6: transistor mode, transistor sense, power regulation . . . . . . . . . . . . . . . . . . . . . . . 24

Figure 16. SO24 mechanical data and package dimensions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

4/27

L9524C Block diagram

1 Block diagram

Figure 1. Block diagram

GND

BAT

CUR

OCT

Supply voltage

monitor

Thermal

shutdown

Diagnostic

output

Control

input

Reference

oscillator

Voltage

controlled

oscillator

Program

Charge/discharge current

Charge

Diagnostic

logic

Control

logic

Overcurrent threshold

pump

Gate

driver

Failure

monitor

(same as channel 1)

(same as channel 2)

Mode input / relay output

Gate

driver

Failure

Channel 3

Channel 4

Channel 1

Channel 2

SP1

SN1

SP2

SN2

SN5

SP3

SN3

SP4 SN4 SN6

5/27

Pins description L9524C

2 Pins description

Figure 2. Pin connection (top view)

Table 2. Pins description

SP1

SN1

SP2

SN5

SN2

BAT

DO GND

VS MS

CP CUR

OCT IO

SO24

SP3

SN3

SP4

SN6

SN4

1312

Pins # Name Function

1 SP1 Positive sense input, glow plug 1

2 G1 Driver output for external high-side power MOSFET, transistor 1

3 SN1 Negative sense input, glow plug 1

4 SP2 Positive sense input, glow plugs 2 and 5

5 G2 Driver output for external high-side power MOSFET, transistor 2

6 SN5 Negative sense input, glow plug 5

7 SN2 Negative sense input, glow plug 2

8 BAT Battery voltage input

9 DO Diagnostic output

10 VS Supply voltage input

11 CP Charge pump output

12 OCT Overcurrent threshold setting

13 IO

Transistor mode: input for selection of power regulation feature Relay mode: output to control external relay driver

14 CUR Power MOSFET gate charge/discharge current setting

15 MS

Mode selection input: transistor modes (transistor sense / shunt sense) / relay mode

16 GND Ground pin

17 CI Control input

18 SN4 Negative sense input, glow plug 4

19 SN6 Negative sense input, glow plug 6

20 G4 Driver output for external high-side power MOSFET, transistor 4

21 SP4 Positive sense input, glow plugs 4 and 6

22 SN3 Negative sense input, glow plug 3

23 G3 Driver output for external high-side power MOSFET, transistor 3

24 SP3 Positive sense input, glow plug 3

6/27

L9524C Electrical specifications

3 Electrical specifications

3.1 Absolute maximum ratings

Table 3. Absolute maximum ratings

Symbol Parameter Value Unit

|dV

BAT

OCT

VMS, V

, VCI,

SP1-4

SN1-6

, V

Supply voltage range -0.3 to 45 V

/dt| Supply voltage slope 10 V/μs

Charge pump voltage range -0.3 to 45 V

Input pin voltage range (BAT, CI, SP1-4, SN1-6) -16 to 45 V

CUR

Input pin voltage range (OCT, CUR, MS, IO) -0.3 to 7 V

Output pin voltage range (DO, G1-4) -16 to 45 V

G1-4

Warning: The device may become damaged if using externally applied

All the pin of the IC are protected against ESD. the verification is performed according to: AEC Q100-002 (HBM) and AEC Q100-011 (CDM).

3.2 Thermal data

Table 4. Thermal data

voltages or currents exceeding these limits!

Symbol Parameter Value Unit

JSD

Operating junction temperature -40 to 125 °C

Junction temperature thermal shutdown threshold 125 to 150 °C

7/27

Electrical specifications L9524C

3.3 Electrical characteristics

5V ≤ VVS;V

≤ 18V, -40°C ≤ TJ ≤ 125°C, unless otherwise specified. The voltages are

BAT

referred to GND and currents are assumed positive, when current flows into the pin.

Table 5. Electrical characteristics

Item Symbol Parameter Test condition Min. Typ. Max. Unit

Supply (VS)

1.1 I

1.2 V

1.3 V

1.4 V

1.5 V

1.6 V

1.7 V

1.8 t

1.9 t

Supply (BAT)

VS uv

VS uvh

VS ol

VS ov

VS ovh

VS ld

VS fil

VS ld

Supply current

1520mA

= 12V 1 10 mA

Undervoltage threshold 4 5 V

Undervoltage threshold hysteresis

(1)

Open-load detection threshold

100 400 mV

5.5 7.2 V

Overvoltage threshold 18 22 V

Overvoltage threshold hysteresis

(1)

0.4 1.6 V

Load dump threshold 28 35 V

Filter time

Load dump delay time

(2)

(1)

12ms

10 μs

2.1 I

2.2 R

2.3 V

2.4 t

BAT leak

BAT

BAT uv

BAT fil

Charge pump (CP)

3.1 V

3.2 I

3.3 V

3.4 f

3.5 t

CP uv

CP fil

≤ 3V

Leakage current

0V ≤ V

BAT

≤ 12V

05μA

-40°C 25 43 150 Internal pull-down resistance

kΩ30°C 25 65 150

125°C 25 106 150

Battery undervoltage threshold

Filter time

(2)

Charge pump voltage ICP = -100μA

> V

(transistor mode) 1 2 V

MS tr

300 760 μs

+5V

+18V

Charging current VCP = VVS + 5V -1500 -100 μA

Charge pump undervoltage threshold

Charge pump frequency

(1)

Filter time

(2)

+3.5V

0.6 7 MHz

400 950 μs

+5V

8/27

L9524C Electrical specifications

Table 5. Electrical characteristics (continued)

Item Symbol Parameter Test condition Min. Typ. Max. Unit

Control input (CI)

4.1 V

4.2 V

4.3 V

4.4 V

4.5 R

4.6 t

4.7 t

CI off

CI on

CI h

CI to

CI fil

CI to

Input “off” level

Input “on” level

Off-to-on hysteresis

(1)

Input “timeout” threshold 1 1.6 V

≤ VVS; -40°C 20 35 120

V Internal pull-up resistance

Filter time

(2)

PWM time-out

(2)

≤ VVS; 30°C 20 53 120

≤ VVS; 125°C 20 87 120

0.6 · V

0.4 · V

0.03 · V

0.04 · V

0.05 · V

0.5 1 ms

50 100 ms

Diagnostic output (DO)

5.1 V

DOL

Output low voltage VVS ≥ 4.5V; IDO ≤ 5mA 0.3 1.5 V

VDO ≤ VVS; -40°C 20 30 120

5.2 R

5.3 I

DO max

Internal pull-up resistance

≤ VVS; 30°C 20 45 120

≤ VVS; 125°C 20 74 120

Current limitation 5 20 mA

Monitoring of currents through glow plugs (SP1-SN1, SP2-SN2, SP3-SN3, SP4-SN4, SP2-SN5, SP4-SN6)

kΩV

6.1 ΔV

6.2 ΔV

6.3 TC

6.4 t

OL fil

OC 0

Open-load threshold 6V ≤ V

1.5V ≤ V VMS < V OCT pin open

1.5V ≤ V

< V

0V ≤ V

Overcurrent threshold

1.5V ≤ V V

MS>VMS tc

ϑ = -40°C; OCT pin open

1.5V ≤ V VMS>V ϑ = -40°C; 0V ≤ V

VMS < V

Overcurrent threshold temperature coefficient

VMS>V OCT pin open

Open-load filter time

(2)

VMS > V

SPX;VSNX

MS tc

SPX;VSNX

MS tc

OCT

SPX;VSNX

MS tc

MS tr

≤ VVS + 3V 6.7 14.7 mV

≤ VVS + 3V

(shunt sense)

≤ VVS + 3V

(shunt sense)

≤ V

CUR

150 185 mV

OCT

0.385

OCT

0.445

≤ VVS + 3V

(transistor sense)

≤ VVS + 3V

(transistor sense)

≤ V

OCT

CUR

(shunt sense)

(transistor sense)

150 290 mV

OCT

0.345

0.008 0.012 K

OCT

0.485

(transistor mode) 1 2 ms

9/27

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+ 18 hidden pages